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Sample records for conrad gastropoda vetigastropoda

  1. Joseph Conrad: International Narrator

    ERIC Educational Resources Information Center

    Walker, George

    2004-01-01

    This article discusses the contribution made by Joseph Conrad's fictional writing to our understanding of cultural awareness. Never comfortable with his adopted English culture, Conrad used his experiences in different parts of the world during his career in the merchant navy to explore in his writing aspects of cultural dissonance and cultural…

  2. Conrad Gessner's Paratexts.

    PubMed

    Blair, Ann

    2016-01-01

    Throughout his prolific publishing career Conrad Gessner composed abundant paratexts which offer valuable insight into his methods of working. Gessner wrote many dedications, only a minority of which were addressed to major patrons of his day. Instead he used them to thank dozens of physicians and scholars for sending him information, images, and manuscripts for his ongoing projects. Gessner acknowledged new arrivals in successive publications and invited further contributions explicitly. In "to the readers" and other passages Gessner called attention to his future publication plans and his skill in working with printers and in editing manuscripts of recently deceased scholars, thereby also encouraging new commissions. Gessner was also a master indexer and innovated especially in drawing up the first index of authors cited for his edition of Stobaeus in 1543 and a new all-purpose index in his Stobaeus of 1549. Many other aspects of Gessner's paratexts warrant further study. PMID:27349033

  3. Klaus Conrad (1905-1961).

    PubMed

    Ploog, Detlev W

    2002-09-01

    Klaus Conrad (1905-1961) was an internationally known figure in the field of neuropsychology and psychopathology. He applied Gestalt psychology to give a better understanding of the aphasias, the symptomatic psychoses and incipient schizophrenia. PMID:12503578

  4. Joseph Conrad's tormented Rescue (fantasy).

    PubMed

    Freedman, William

    2014-02-01

    Joseph Conrad was a notoriously tormented writer for whom the creative act was often a punishment severe enough to drive him into paralyzing depressions that delayed the completion of his novels, sometimes for years. By far the most agonizing of these projects was The Rescue, a novel he began in 1898, abandoned a year later, tried unsuccessfully to continue several times over the next two decades, but was only able to resume in 1918 and to complete, after another tortured two-year struggle, in 1920. An explanation for this incapacity, that is powerfully suggested by the novel's evocative title and perhaps unintentionally ironic subtitle (A Romance of the Shallows) has not yet been explored. Using Freud's 1910 essay on the rescue fantasy, "Contributions to the Psychology of Love: A Special Type of Choice of Object Made by Men," and Emanuel Berman's instructive revision and expansion of the concept in his 2003 American Imago essay, "Ferenczi, Rescue, and Utopia," I argue that a substantial explanation for Conrad's tormented history with The Rescue is ascribable to its quite remarkably faithful treatment of a rescue fantasy with deep and disabling resonance for its author. More specifically, the difficulty was compounded by the novel's dramatization of the soul-crushing conflict between two such fantasies: one in the service of the masculine ideal of unflinching dedication to a heroic purpose, the other promising satisfaction to the equally potent demands of emotional and sexual desire. Features of Conrad's narrative fit so tightly and consistently with the theory as Freud (and Abraham) proposed and as Berman elaborated it that The Rescue offers itself as one of those rare and reinforcing instances wherein the literary text seems to validate the psychoanalytic theory at least as persuasively as the theory "understands" the text.

  5. Joseph Conrad's tormented Rescue (fantasy).

    PubMed

    Freedman, William

    2014-02-01

    Joseph Conrad was a notoriously tormented writer for whom the creative act was often a punishment severe enough to drive him into paralyzing depressions that delayed the completion of his novels, sometimes for years. By far the most agonizing of these projects was The Rescue, a novel he began in 1898, abandoned a year later, tried unsuccessfully to continue several times over the next two decades, but was only able to resume in 1918 and to complete, after another tortured two-year struggle, in 1920. An explanation for this incapacity, that is powerfully suggested by the novel's evocative title and perhaps unintentionally ironic subtitle (A Romance of the Shallows) has not yet been explored. Using Freud's 1910 essay on the rescue fantasy, "Contributions to the Psychology of Love: A Special Type of Choice of Object Made by Men," and Emanuel Berman's instructive revision and expansion of the concept in his 2003 American Imago essay, "Ferenczi, Rescue, and Utopia," I argue that a substantial explanation for Conrad's tormented history with The Rescue is ascribable to its quite remarkably faithful treatment of a rescue fantasy with deep and disabling resonance for its author. More specifically, the difficulty was compounded by the novel's dramatization of the soul-crushing conflict between two such fantasies: one in the service of the masculine ideal of unflinching dedication to a heroic purpose, the other promising satisfaction to the equally potent demands of emotional and sexual desire. Features of Conrad's narrative fit so tightly and consistently with the theory as Freud (and Abraham) proposed and as Berman elaborated it that The Rescue offers itself as one of those rare and reinforcing instances wherein the literary text seems to validate the psychoanalytic theory at least as persuasively as the theory "understands" the text. PMID:24555549

  6. On some Vetigastropoda (Mollusca, Gastropoda) from the Plio-Pleistocene of the Philippines with descriptions of three new species.

    PubMed

    Helwerda, Renate Ariane; Wesselingh, Frank Pieter; Williams, Suzanne T

    2014-01-21

    We studied representatives of seven vetigastropod families in an extremely well-preserved Plio-Pleistocene mollusc fauna found in relatively deep water sediments (c. 200-300 m paleodepth) from the north-western Philippines. The fauna is systematically described and its paleoenvironmental and paleobiogeographical character is explored. Twenty-six species of gastropods were studied, three of which are described as new: Halystina conoidea n. sp., Calliotropis arenosa n. sp. and Ethminolia wareni n. sp. Four new combinations are proposed: Pseudotalopia taiwanensis (Chen, 2006), Solariella segersi (Poppe, Tagaro & Dekker, 2006), Zetela tabakotanii (Poppe, Tagaro & Dekker, 2006) and Ilanga konos (Vilvens, 2009). Fourteen species are known living. Most extant species nowadays occur around the Philippines. Two of the species also occur in Neogene deposits from western Pacific islands. The new fauna offers insights into the character of relatively deep water Indo-West Pacific mollusc faunas prior to the onset of the late Quaternary ice ages.

  7. The British Novel: Conrad to the Present.

    ERIC Educational Resources Information Center

    Wiley, Paul L.

    Intended for advanced undergraduate and graduate students who desire a useful research tool, this bibliography cites the works of and about British novelists, beginning with Joseph Conrad and terminating in 1950. The listings are selective with proper emphasis given to less celebrated but distinctive writers. A preface explaining the numerous…

  8. ["Trema, apophany, apocalypse"--is Conrad's phase model empirically founded?].

    PubMed

    Hambrecht, M; Häfner, H

    1993-12-01

    Among several phase models of beginning schizophrenia, the study by Conrad ("Die beginnende Schizophrenie. Versuch einer Gestaltanalyse des Wahns") was particularly impressive in German psychiatry. The ABC-Schizophrenia-study with its representative sample of 267 first-admissions and a careful retrospective assessment of emerging symptomatology made it possible to test the empirical basis of Conrad's model. In this operationalization "trema" was confirmed as the frequent first stage of the disease process, whereas Conrad's hypothesized order of the two following phrases (first "apophany", then "apocalypse") could not be validated. Therefore, Conrad's model cannot completely be generalized. Because the methods employed so far have some limitations, analyses of additional data (especially reports by significant others) may control and probably enhance the presented results. PMID:8112705

  9. Fine morphology of the jaw apparatus of Puncturella noachina (Fissurellidae, Vetigastropoda).

    PubMed

    Vortsepneva, Elena; Ivanov, Dmitry; Purschke, Günter; Tzetlin, Alexander

    2014-07-01

    Jaws of various kinds occur in virtually all groups of Mollusca, except for Polyplacophora and Bivalvia. Molluscan jaws are formed by the buccal epithelium and either constitute a single plate, a paired formation or a serial structure. Buccal ectodermal structures in gastropods are rather different. They can be nonrenewable or having final growth, like the hooks in Clione (Gastropoda, Gymnosomata). In this case, they are formed by a single cell. Conversely, they can be renewable during the entire life span and in this case they are formed by a set of cells, like the formation of the radula. The fine structure of the jaws was studied in the gastropod Puncturella noachina. The jaw is situated in the buccal cavity and consists of paired elongated cuticular plates. On the anterior edge of each cuticular plate there are numerous longitudinally oriented rodlets disposed over the entire jaw surface and immersed into a cuticular matrix. The jaw can be divided into four zones situated successively toward the anterior edge: 1) the posterior area: the zone of formation of the thick cuticle covering the entire jaw and forming the electron-dense outer layer of the jaw plate; 2) the zone of rodlet formation; 3) the zone of rodlet arrangement; and 4) the anterior zone: the free scraping edge of the plate, or the erosion zone. In the general pattern of jaw formation, Puncturella noachina resembles Testudinalia tessulata (Patellogastropoda) studied previously. The basis of the jaw is a cuticular plate formed by the activity of the strongly developed microvillar apparatus of the gnathoepithelium. However, the mechanism of renewal of the jaw anterior part in P. noachina is much more complex as its scraping edge consists not just of a thick cuticular matrix rather than of a system of denticles being the projecting endings of rodlets. PMID:24549973

  10. APOLLO 12: C.Conrad Jr. collects geological samples

    NASA Technical Reports Server (NTRS)

    1974-01-01

    APOLLO 12: 'Pete' Conrad collects samples from the lunar surface, while at the same time adjusting to, and remarking on, the working conditions. From the film documentary 'APOLLO 12: 'Pinpoint for Science'', part of a documentary series on the APOLLO missions made in the early '70's and narrated by Burgess Meredith. APOLLO 12: Second manned lunar landing and return with Charles 'Pete' Conrad, Jr., Richard F. Gordon, and Alan F. Bean. Landed in the Ocean of Storms on November 19, 1969; deployed television camera and ALSEP experiments; two EVA's performed; collected core samples and lunar materials; photographed and retrieved parts from surveyor 3 spacecraft. Mission duration 244hrs 36min 24sec

  11. Astronaut Charles Conrad checks out Human Vestibular Function experiment

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Astronaut Charles Conrad Jr., commander of the first manned Skylab mission, checks out the Human Vestibular Function, Experiment M131, during Skylab training at JSC. Conrad is in the work and experiments compartment of the crew quarters of the Skylab Orbital Workshop (OWS) trainer at JSC. The reference sphere with a magnetic rod is used by the astronaut to indicate body orientation non-visually. The litter chair in which he is seated can be rotated by a motor at its base or, when not being rotated, can tilt forward, backward or to either side.

  12. Astronauts Conrad and Kerwin practice Human Vestibular Function experiment

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Astronaut Charles Conrad Jr., commander of the first manned Skylab mission, checks out the Human Vestibular Function, Experiment M131, during Skylab training at JSC. Scientist-Astronaut Joseph P. Kerwin, science pilot of the mission, goes over a checklist. The two men are in the work and experiments compartment of the crew quarters of the Skylab Orbital Workshop (OWS) trainer at JSC.

  13. Astronauts Conrad and Gordon demonstrate tethering procedures for news media

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Astronauts Charles Conrad (left), command pilot, and Richard F. Gordon (right), pilot, demonstrate tether procedure between their Gemini 11 spacecraft and the Agena Target Docking Vehicle at the post flight press conference. They use models of their spacecraft and its Agena to illustrate maneuvers.

  14. Astronauts Conrad and Gordon demonstrate tethering procedures for news media

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Astronauts Charles Conrad (center), command pilot, and Richard F. Gordon (right), pilot, demonstrate tether procedure between their Gemini 11 spacecraft and the Agena Target Docking Vehicle at the post flight press conference. They use models of their spacecraft and its Agena to illustrate maneuvers. At left is George Low, Deputy Director, Manned Spacecraft Center, Houston.

  15. Astronaut Charles Conrad trims hair of Astronaut Paul Weitz

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Astronaut Charles Conrad Jr., Skylab 2 commander, trims the hair of Astronaut Paul J. Weitz, Skylab 2 pilot, during the 28-day Skylab 2 mission in Earth orbit. They are in the crew quarters wardroom of the Orbital Workshop of the Skylab 1 and 2 space station. Weitz is holding a vacuum hose in his right hand. This picture was taken by Scientist-Astronaut Joseph P. Kerwin, Skylab 2 science pilot.

  16. Astronaut Joseph Kerwin takes blood sample from Astronaut Charles Conrad

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Scientist-Astronaut Joseph P. Kerwin (right), Skylab 2 science pilot and a doctor of medicine, takes a blood sample from Astronaut Charles Conrad Jr., Sylab 2 commander, as seen in this reproduction taken from a color television transmission made by a TV camera aboard the Skylab 1 and 2 space station cluster in Earth orbit. The blood sampling was part of the Skylab Hematology and Immunology Experiment M110 series.

  17. Joseph Conrad's Empathy for Exploited Africans in "The Heart of Darkness."

    ERIC Educational Resources Information Center

    Farley, Ena L.

    1990-01-01

    Seemingly contradictory positions of J. Conrad as both a racist and an opponent of race-based imperial practices are discussed with reference to "The Heart of Darkness." It is argued that Conrad made a conscious effort to shake off the racial theories of the time and to deplore imperial racism. (SLD)

  18. Astronauts Alan Bean and Charles Conrad on Lunar Surface

    NASA Technical Reports Server (NTRS)

    1969-01-01

    The second manned lunar landing mission, Apollo 12 launched from launch pad 39-A at Kennedy Space Center in Florida on November 14, 1969 via a Saturn Five launch vehicle. The Saturn V vehicle was developed by the Marshall Space Flight Center (MSFC) under the direction of Dr. Wernher von Braun. Aboard Apollo 12 was a crew of three astronauts: Alan L. Bean, pilot of the Lunar Module (LM), Intrepid; Richard Gordon, pilot of the Command Module (CM), Yankee Clipper; and Spacecraft Commander Charles Conrad. The LM, Intrepid, landed astronauts Conrad and Bean on the lunar surface in what's known as the Ocean of Storms while astronaut Richard Gordon piloted the CM, Yankee Clipper, in a parking orbit around the Moon. Their lunar soil activities included the deployment of the Apollo Lunar Surface Experiments Package (ALSEP), finding the unmanned Surveyor 3 that landed on the Moon on April 19, 1967, and collecting 75 pounds (34 kilograms) of rock samples. In this photograph, one of the astronauts on the Moon's surface is holding a container of lunar soil. The other astronaut is seen reflected in his helmet. Apollo 12 safely returned to Earth on November 24, 1969.

  19. Skylab beverage container filled with orange juice held by Astronaut Conrad

    NASA Technical Reports Server (NTRS)

    1973-01-01

    An accordian-style beverage dispenser filled with orange juice is held by Astronaut Charles Conrad Jr., Skylab 2 commander, in this close-up view which is a reproduction taken from a color television transmission made by a TV camera aboard the Skylab 1 and 2 space station cluster in Earth orbit. Conrad (head and face not in view) is seated at the wardroom table in the crew quarters of the Orbital Workshop. The dispenser contained beverage crystals, and Conrad has just added the prescribed amount of water to make the orange drink.

  20. Recent Developments in the CONRAD Code regarding Experimental Corrections

    NASA Astrophysics Data System (ADS)

    Archier, P.; De Saint Jean, C.; Kopecky, S.; Litaize, O.; Noguère, G.; Schillebeeckx, P.; Volev, K.

    2013-03-01

    The CONRAD code is an object-oriented software tool developed at CEA Cadarache since 2005 to deal with problems arising during the evaluation process (data assimilation and analysis, physical modelling, propagation of uncertainties…). This paper will present recent developments concerning the experimental corrections, which are required when a neutron resonance shape analysis is performed. Several experimental aspects are detailed in this work: the possibility to use spectra in energy as well as in time, the implementation of both analytical (Chi-Square) and Monte-Carlo resolution functions, the sample homogeneity corrections using log-normal distributions. Each development aspect is illustrated with several examples and comparisons with other resonance analysis codes (SAMMY, REFIT).

  1. Unit 5, STA. 53+25+RB, Conrad buildingcontext Johnstown Local Flood ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Unit 5, STA. 53+25+RB, Conrad building-context - Johnstown Local Flood Protection Project, Beginning on Conemaugh River approx 3.8 miles downstream from confluence of Little Conemaugh & Stony Creek Rivers at Johnstown, Johnstown, Cambria County, PA

  2. Unit 5, STA. 53+25+RB, Conrad buildingdetail Johnstown Local Flood ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Unit 5, STA. 53+25+RB, Conrad building-detail - Johnstown Local Flood Protection Project, Beginning on Conemaugh River approx 3.8 miles downstream from confluence of Little Conemaugh & Stony Creek Rivers at Johnstown, Johnstown, Cambria County, PA

  3. Diamond dosimetry: Outcomes of the CANDIDO and CONRAD INFN projects

    NASA Astrophysics Data System (ADS)

    Bucciolini, M.; Borchi, E.; Bruzzi, M.; Casati, M.; Cirrone, P.; Cuttone, G.; De Angelis, C.; Lovik, I.; Onori, S.; Raffaele, L.; Sciortino, S.

    2005-10-01

    This paper reviews the main results of the study, carried out in the framework of the Italian National Institute of Nuclear Physics (INFN, Istituto Nazionale di Fisica Nucleare) projects, namely CANDIDO and CONRAD, on natural and synthetic diamond-based dosimeters for clinical radiotherapy. Characteristics of diamond such as radiation hardness, high sensitivity, tissue equivalence, etc., make this material interesting for dosimetry applications. For some years, natural diamonds have been commercially available for on-line radiotherapy dosimetry. Nevertheless, recent developments in the "Chemical Vapour Deposition" (CVD) technique have addressed the attention on synthetic samples that potentially could be grown at low cost and with features suitable for dosimetric use. Several samples, differently grown and with different electrical contacts, have been compared by measuring their current response during irradiation with high-energy photon, electron and proton beams. Properties of dosimetric interest such as linearity, pre-irradiation dose, dose rate dependence, stability and rise time have been investigated. The results obtained so far within the INFN collaboration demonstrate the suitability of natural diamond detectors for many radiotherapy applications and the great potential of CVD diamond-based devices even though, at present, the commercial natural diamond dosimeters have a better behaviour with respect to the synthetic samples. Further efforts have to be made mainly to improve the dynamic of response and performance stability.

  4. Defense in the aeolidoidean genus Phyllodesmium (Gastropoda).

    PubMed

    Bogdanov, Alexander; Kehraus, Stefan; Bleidissel, Sabrina; Preisfeld, Gela; Schillo, Dorothee; Piel, Jörn; Brachmann, Alexander O; Wägele, Heike; König, Gabriele M

    2014-09-01

    The genus Phyllodesmium (Aeolidoidea, Gastropoda) comprises shell-less marine snails, whose defense strategies are not well investigated yet. Here we report results of the first chemical investigation of P. briareum, as well as a re-investigation of P. longicirrum and P. magnum. Briarane diterpenes were isolated from P. briareum, and their origin could be traced to its prey organism Briareum sp. (Octocorallia). Considerable enrichment of the soft coral secondary metabolites in the slug was shown. Re-investigation of P. magnum led to isolation of cembrane diterpenes, 2-phenylethylamide, and furano sesquiterpenes. Sequestration of chemicals seems to have influenced speciation and evolution of Phyllodesmium species. Structural similarity or dissimilarity of particular slug metabolites suggests a closer, or more distant relationship of the respective Phyllodesmium taxa. PMID:25244950

  5. Folk Psychology or Semantic Entailment? Comment on Rips and Conrad (1989).

    ERIC Educational Resources Information Center

    Fellbaum, Christiane; Miller, George A.

    1990-01-01

    L. J. Rips and F. G. Conrad (1989) suggested that the results from their experiments on folk beliefs about the mind provided clues to differences between folk and scientific psychology. An alternative explanation is developed that holds that their results shed no light on folk theories of the mind but are quite general. (SLD)

  6. Astronauts Conrad and Cooper slice cake on U.S.S. Lake Champlain

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Astronauts Charles Conrad Jr. (left) and L. Gordon Cooper Jr. prepate to slice into the huge cake prepared for them by the cooks onboard the aircraft carrier U.S.S. Lake Champlain. They are using ornamental Navy swords for knives.

  7. Gemini 11 Commander Conrad and Pilot Gordon at post flight press conference

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Gemini 11 Commander Charles Conrad, Jr (left) and Pilot Richard F. Gordon, Jr describe mission activities during their post flight press conference at JSC. Gordon at the microphone talks about the extravehicular activity (EVA) photo projected behind the two crewmembers. During the EVA Gordon attached a tether to the Agena and retrieved a nuclear emulsion experiment package.

  8. Astronauts Cooper and Conrad arrive aboard U.S.S. Lake Champlain

    NASA Technical Reports Server (NTRS)

    1965-01-01

    A red-carpet welcome was staged for Astronauts L. Gordon Cooper Jr. and Charles Conrad Jr. as they arrive aboard the aircraft carrier U.S.S. Lake Champlain. They had been recovered from the Atlantic after the splashdown of their Gemini 5 spacecraft.

  9. Conrad Deep, Northern Red Sea: Development of an early stage ocean deep within the axial depression

    NASA Astrophysics Data System (ADS)

    Ehrhardt, A.; Hübscher, C.; Gajewski, D.

    2005-12-01

    The northern Red Sea represents a continental rift in its final stage and close to the following stage of seafloor spreading. Ocean deeps within the evaporites of the northern Red Sea seem to accompany this process and are thought to be surface expressions of first seafloor spreading cells. In 1999 during R/V Meteor cruise M44/3 a dense multichannel seismic and hydroacoustic survey was conducted in order to investigate the initial formation process of the Conrad Deep, a young northern Red Sea deep. Three seismic units were differentiated in the uppermost part of the Miocene evaporites and the Plio-Quaternary sediments. A weakness zone within the evaporites, oblique to the main extension direction of the Red Sea, led to a transtension process within the evaporites that opened the deep. Its formation is directly related to the emplacement of magmatic bodies in its vicinity and the focusing of the Red Sea extension to the axial depression. The Conrad Deep is an intra-evaporite basin that cannot be regarded as surficial expression of a basement structure as the low shear strength of the evaporites decouple the sediments from the basement. However, its position and shape in combination with the accompanying geophysical anomalies point to a strong correlation with the Red Sea rifting process.

  10. The mitochondrial genome of Pomacea maculata (Gastropoda: Ampullariidae).

    PubMed

    Yang, Qianqian; Liu, Suwen; Song, Fan; Li, Hu; Liu, Jinpeng; Liu, Guangfu; Yu, Xiaoping

    2016-07-01

    The golden apple snail, Pomacea maculata Perry, 1810 (Gastropoda: Ampullariidae) is one of the most serious invasive alien species from the native range of South America. The mitochondrial genome of P. maculata (15 516 bp) consists of 37 genes (13 protein-coding genes, two rRNAs, and 22 tRNAs) and a non-coding region with a 16 bp repeat unit. Most mitochondrial genes of P. maculata are distributed on the H-strand, except eight tRNA genes, which are encoded on the L-strand. A phylogenetic analysis showed that there was a close relationship between P. maculata and another invasive golden apple snail species, Pomacea canaliculata (Lamarck, 1822).

  11. Circulation of images and graphic practices in Renaissance natural history: the example of Conrad Gessner.

    PubMed

    Egmond, Florike; Kusukawa, Sachiko

    2016-01-01

    Conrad Gessner's Historia animalium is a compilation of information from a variety of sources: friends, correspondents, books, broadsides, drawings, as well as his own experience. The recent discovery of a cache of drawings at Amsterdam originally belonging to Gessner has added a new dimension for research into the role of images in Gessner's study of nature. In this paper, we examine the drawings that were the basis of the images in the volume of fishes. We uncovered several cases where there were multiple copies of the same drawing of a fish (rather than multiple drawings of the samefish), which problematizes the notion of unique "original" copies and their copies. While we still know very little about the actual mechanism of, or people involved in, commissioning or generating copies of drawings, their very existence suggests that the images functioned as an important medium in the circulation of knowledge in the early modern period.

  12. Circulation of images and graphic practices in Renaissance natural history: the example of Conrad Gessner.

    PubMed

    Egmond, Florike; Kusukawa, Sachiko

    2016-01-01

    Conrad Gessner's Historia animalium is a compilation of information from a variety of sources: friends, correspondents, books, broadsides, drawings, as well as his own experience. The recent discovery of a cache of drawings at Amsterdam originally belonging to Gessner has added a new dimension for research into the role of images in Gessner's study of nature. In this paper, we examine the drawings that were the basis of the images in the volume of fishes. We uncovered several cases where there were multiple copies of the same drawing of a fish (rather than multiple drawings of the samefish), which problematizes the notion of unique "original" copies and their copies. While we still know very little about the actual mechanism of, or people involved in, commissioning or generating copies of drawings, their very existence suggests that the images functioned as an important medium in the circulation of knowledge in the early modern period. PMID:27349032

  13. [The response to Wilhelm Conrad Röntgen's discovery in Berlin].

    PubMed

    Schüttmann, W

    1995-01-01

    In early January 1896 Wilhelm Conrad Röntgen sent offprints to several colleagues of his to make them acquainted with his discovery of the X-rays. From January 5, 1896 newspapers started reporting on that discovery worldwide from Vienna. In several cities the news immediately set off corresponding scientific activities among specialists. This paper looks into such activities carried out in Berlin to show how promptly Röntgen's discovery was taken up, with a number of priorities having been set in the capital of the German Reich. The X-ray photographs which Röntgen had forwarded together with his offprints were displayed and discussed at a meeting of the Berlin Physical Society as early as on January 4, 1896, making his discovery known to the public for the first time. On January 6, 1896 the discovery and photographs were presented at a session of the Berlin Association of Internal Medicine and its diagnostic application was discussed in the medical community for the first time. A few days after that, the first photographs shot by other authors after Röntgen, and their diagnostic use, were demonstrated in Berlin. Finally, Röntgen's early visit to Emperor William II on January 12, 1896, which led to the speedy introduction of the X-day technique into German military medicine, is discussed in detail.

  14. Gravity Variations Induced by Changing Snowpack Observed at Conrad Observatory (Austria)

    NASA Astrophysics Data System (ADS)

    Ressl, Hans; Dorninger, Manfred; Meurers, Bruno

    2016-04-01

    Hydrological processes are usually associated with mass transport. This induces gravity variations observed by superconducting gravimeter (SG) masking the pure geodynamical signal. The present study focusses specifically on gravity variations due to snow accumulation and melting. Measurements of the gravity signal are taken from the SG GWR C025 located at the Conrad Observatory (Austria) in an underground laboratory at about 1000m altitude. In snow rich winters a snowpack of one meter in depth or even more can be observed at this location. Snow height is measured at three different locations to get an idea of its variability. At one place additionally the weight of the snow pack is determined which allows to calculate the snow water equivalent. Gravitational signals are rather different for the accumulation and ablation phase, not only due to the different time scales of these processes but also due to the complex way path of melting water entering the ground beneath of the SG. Two methods, rainfall admittance function and Bouguer reduction, are used to account for the effect of the snow pack. Both have their strengths and weaknesses. They work better for short-term mass transports than for long lasting ones because in the latter case interference with signals of other environmental processes gets more prominent. A few case studies including both accumulation and ablation of snow on different time scales will be discussed.

  15. Analysis of the CONRAD computational problems expressing only stochastic uncertainties: neutrons and protons.

    PubMed

    Gualdrini, G; Tanner, R J; Agosteo, S; Pola, A; Bedogni, R; Ferrari, P; Lacoste, V; Bordy, J-M; Chartier, J-L; de Carlan, L; Gomez Ros, J-M; Grosswendt, B; Kodeli, I; Price, R A; Rollet, S; Schultz, F; Siebert, B; Terrissol, M; Zankl, M

    2008-01-01

    Within the scope of CONRAD (A Coordinated Action for Radiation Dosimetry) Work Package 4 on Computational Dosimetry jointly collaborated with the other research actions on internal dosimetry, complex mixed radiation fields at workplaces and medical staff dosimetry. Besides these collaborative actions, WP4 promoted an international comparison on eight problems with their associated experimental data. A first set of three problems, the results of which are herewith summarised, dealt only with the expression of the stochastic uncertainties of the results: the analysis of the response function of a proton recoil telescope detector, the study of a Bonner sphere neutron spectrometer and the analysis of the neutron spectrum and dosimetric quantity H(p)(10) in a thermal neutron facility operated by IRSN Cadarache (the SIGMA facility). A second paper will summarise the results of the other five problems which dealt with the full uncertainty budget estimate. A third paper will present the results of a comparison on in vivo measurements of the (241)Am bone-seeker nuclide distributed in the knee. All the detailed papers will be presented in the WP4 Final Workshop Proceedings.

  16. Rigorous noise test and calibration check of strong-motion instrumentation at the Conrad Observatory in Austria.

    NASA Astrophysics Data System (ADS)

    Steiner, R.; Costa, G.; Lenhardt, W.; Horn, N.; Suhadolc, P.

    2012-04-01

    In the framework of the European InterregIV Italy/Austria project: "HAREIA - Historical and Recent Earthquakes in Italy and Austria" the Central Institute for Meteorology and Geodynamics (ZAMG) and Mathematic and Geosciences Department of University of Trieste (DMG) are upgrading the transfrontier seismic network of South-Eastern Alps with new 12 accelerometric stations to enhance the strong motion instrument density near the Austria/Italy border. Various public institutions of the provinces Alto Adige (Bolzano Province), Veneto (ARPAV) and Friuli Venezia Giulia (Regional Civil Defense) in Italy and in the Austrian province of Tyrol are involved in the project. The site selection was carried out to improve the present local network geometry thus meeting the needs of public Institutions in the involved regions. In Tyrol and Alto Adige some strategic buildings (hospitals and public buildings) have been selected, whereas in Veneto and Friuli Venezia Giulia the sites are in the free field, mainly located near villages. The instruments will be installed in an innovative box, designed by ZAMG, that provides electric and water isolation. The common choice regarding the instrument selection has been the new Kinemetrics Basalt ® accelerograph to guarantee homogeneity with the already installed instrumentation and compatibility with the software already in use at the different seismic institutions in the area. Prior to deployment the equipment was tested at the Conrad Observatory and a common set-up has been devised. The Conrad Observatory, seismically particularly quiet, permits to analyze both the sensor and the acquisition system noise. The instruments were connected to the network and the data sent in real-time to the ZAMG data center in Vienna and the DMG data center in Trieste. The data have been collected in the database and analyzed using signal processing modules PQLX and Matlab. The data analysis of the recordings at the ultra-quiet Conrad Observatory pointed out

  17. The epigenetic landscape in the course of time: Conrad Hal Waddington's methodological impact on the life sciences.

    PubMed

    Baedke, Jan

    2013-12-01

    It seems that the reception of Conrad Hal Waddington's work never really gathered speed in mainstream biology. This paper, offering a transdisciplinary survey of approaches using his epigenetic landscape images, argues that (i) Waddington's legacy is much broader than is usually recognized--it is widespread across the life sciences (e.g. stem cell biology, developmental psychology and cultural anthropology). In addition, I will show that (ii) there exist as yet unrecognized heuristic roles, especially in model building and theory formation, which Waddington's images play within his work. These different methodological facets envisioned by Waddington are used as a natural framework to analyze and classify the manners of usage of epigenetic landscape images in post-Waddingtonian 'landscape approaches'. This evaluation of Waddington's pictorial legacy reveals that there are highly diverse lines of traditions in the life sciences, which are deeply rooted in Waddington's methodological work.

  18. Sphenodiscus pleurisepta (Conrad, 1857) from the Maastrichtian La Tabla Formation in the Upper Magdalena Valley, Tolima, Colombia

    NASA Astrophysics Data System (ADS)

    Patarroyo, Pedro; Bengtson, Peter; Guerrero, Javier

    2010-11-01

    The La Tabla Formation is an important petroleum reservoir in the Upper Magdalena Valley of Colombia. It was deposited in regressive and lowstand systems tracts and comprises a succession of lower shoreface to coastal plain deposits. A section in the Talora Creek, near the village of Piedras, Department of Tolima, exposes 90 m of a progradational to aggradational succession composed of very fine sandstones to medium-grained pebble conglomerates, with abundant planktic and benthic foraminifers as well as bivalves and ammonites. A few well-preserved phragmocones of the ammonite Sphenodiscus pleurisepta ( Conrad, 1857), collected from a level 63 m above the base of the formation, are here described and the chronostratigraphic position of the species discussed. In the Western Interior Basin of North America, S. pleurisepta ranges from the upper lower Maastrichtian Baculites clinolobatus Zone through the upper Maastrichtian Jeletzkytes nebrascensis Zone. The present findings support previous datings of the La Tabla Formation as Maastrichtian on the basis of foraminifers.

  19. Generation of 238U Covariance Matrices by Using the Integral Data Assimilation Technique of the CONRAD Code

    NASA Astrophysics Data System (ADS)

    Privas, E.; Archier, P.; Bernard, D.; De Saint Jean, C.; Destouche, C.; Leconte, P.; Noguère, G.; Peneliau, Y.; Capote, R.

    2016-02-01

    A new IAEA Coordinated Research Project (CRP) aims to test, validate and improve the IRDF library. Among the isotopes of interest, the modelisation of the 238U capture and fission cross sections represents a challenging task. A new description of the 238U neutrons induced reactions in the fast energy range is within progress in the frame of an IAEA evaluation consortium. The Nuclear Data group of Cadarache participates in this effort utilizing the 238U spectral indices measurements and Post Irradiated Experiments (PIE) carried out in the fast reactors MASURCA (CEA Cadarache) and PHENIX (CEA Marcoule). Such a collection of experimental results provides reliable integral information on the (n,γ) and (n,f) cross sections. This paper presents the Integral Data Assimilation (IDA) technique of the CONRAD code used to propagate the uncertainties of the integral data on the 238U cross sections of interest for dosimetry applications.

  20. Petrography and geochemistry of basaltic rocks from the Conrad fracture zone on the America-Antarctica Ridge

    NASA Astrophysics Data System (ADS)

    le Roex, Anton P.; Dick, Henry J. B.

    1981-06-01

    Intrusive and extrusive basaltic rocks have been dredged from the Conrad fracture zone (transecting the slow-spreading America-Antarctica Ridge). The majority of rocks recovered are holocrystalline with the dominant mineral assemblage being plagioclase plus clinopyroxene with or without minor Fe-Ti oxides (olivine occurs in only three samples) and many of the samples show evidence of extensive alteration. Secondary minerals include chlorite, actinolite, K- and Na-feldspar, analcite and epidote. In terms of bulk chemistry the rocks are characterized by their generally evolved and highly variable compositions (e.g. Mg *=0.65-0.35;TiO 2=0.7-3.6%;Zr=31-374ppm;Nb=<3-21ppm;Y=17-96ppm;Ni=100-9ppm ), but with respect to the immobile incompatible element ratios (e.g. Zr/Nb, Y/Nb, La/Sm) are similar to "normal" or depleted mid-oceanic ridge basalts. Quantitative major and trace element modelling indicate that most of the variation observed can be attributed to low-pressure fractional crystallization of plagioclase plus clinopyroxene in approximately equal proportions with or without minor Fe-Ti oxides. The range in composition can be accounted for by up to 76% fractional crystallization. Although ferrobasalts have not frequently been associated with slow spreading ridges, the extreme differentiation observed in the Conrad fracture zone basalts implies some additional constraint other than spreading rate on the formation of ferrobasalt and reaffirms the importance of extensive crustal differentiation during the production of this basalt type.

  1. Bathymetric distribution patterns of Southern Ocean macrofaunal taxa: Bivalvia, Gastropoda, Isopoda and Polychaeta

    NASA Astrophysics Data System (ADS)

    Brandt, Angelika; Linse, Katrin; Schüller, Myriam

    2009-11-01

    The aim of this study is to compare the depth distributions of four major Southern Ocean macrobenthic epi- and infaunal taxa, the Bivalvia, Gastropoda, Isopoda, and Polychaeta, from subtidal to abyssal depth. All literature data up to summer 2008, as well as the unpublished data from the most recent ANDEEP I-III (Antarctic benthic deep-sea biodiversity: colonisation history and recent community patterns) expeditions to the Southern Ocean deep sea are included in the analysis. Benthic invertebrates in the Southern Ocean are known for their wide bathymetric ranges. We analysed the distributions of four of the most abundant and species-rich taxa from intertidal to abyssal (5200 m) depths in depth zones of 100 m. The depth distributions of three macrofaunal classes (Bivalvia, Gastropoda, Polychaeta) and one order (Isopoda) showed distinct differences. In the case of bivalves, gastropods and polychaetes, the number of species per depth zone decreased from the shelf to the slope at around 1000 m depth and then showed stable low numbers. The isopods showed the opposite trend; they were less species rich in the upper 1000 m but increased in species numbers from the slope to bathyal and abyssal depths. Depth ranges of families of the studied taxa (Bivalvia: 31 families, Gastropoda: 60, Isopoda: 32, and Polychaeta: 46 families) were compiled and illustrated. At present vast areas of the deep sea in the Southern Ocean remain unexplored and species accumulation curves showed that only a fraction of the species have been discovered to date. We anticipate that further investigations will greatly increase the number of species known in the Southern Ocean deep sea.

  2. Original molluscan radula: comparisons among Aplacophora, Polyplacophora, Gastropoda, and the Cambrian fossil Wiwaxia corrugata.

    PubMed

    Scheltema, Amélie H; Kerth, Klaus; Kuzirian, Alan M

    2003-08-01

    As the original molluscan radula is not known from direct observation, we consider what the form of the original radula may have been from evidence provided by neomenioid Aplacophora (Solenogastres), Gastropoda, Polyplacophora, and the Cambrian fossil Wiwaxia corrugata (Matthews). Conclusions are based on direct observation of radula morphology and its accessory structures (salivary gland ducts, radular sac, anteroventral radular pocket) in 25 species and 16 genera of Aplacophora; radula morphogenesis in Aplacophora; earliest tooth formation in Gastropoda (14 species among Prosobranchia, Opisthobranchia, and Pulmonata); earliest tooth formation in four species of Polyplacophora; and the morphology of the feeding apparatus in W. corrugata. The existence of a true radula membrane and of membranoblasts and odontoblasts in neomenioids indicates that morphogenesis of the aplacophoran radula is homologous to that in other radulate Mollusca. We conclude from p redness of salivary gland ducts, a divided radular sac, and a pair of anteroventral pockets that the plesiomorphic state in neomenioids is bipartite, formed of denticulate bars that are distichous (two teeth per row) on a partially divided or fused radula membrane with the largest denticles lateral, as occurs in the genus Helicoradomenia. The tooth morphology in Helicoradomenia is similar to the feeding apparatus in W. corrugata. We show that distichy also occurs during early development in several species of gastropods and polyplacophorans. Through the rejection of the null hypothesis that the earliest radula was unipartite and had no radula membrane, we conclude that the original molluscan radula was similar to the radula found in Helicoradomena species.

  3. Original molluscan radula: comparisons among Aplacophora, Polyplacophora, Gastropoda, and the Cambrian fossil Wiwaxia corrugata.

    PubMed

    Scheltema, Amélie H; Kerth, Klaus; Kuzirian, Alan M

    2003-08-01

    As the original molluscan radula is not known from direct observation, we consider what the form of the original radula may have been from evidence provided by neomenioid Aplacophora (Solenogastres), Gastropoda, Polyplacophora, and the Cambrian fossil Wiwaxia corrugata (Matthews). Conclusions are based on direct observation of radula morphology and its accessory structures (salivary gland ducts, radular sac, anteroventral radular pocket) in 25 species and 16 genera of Aplacophora; radula morphogenesis in Aplacophora; earliest tooth formation in Gastropoda (14 species among Prosobranchia, Opisthobranchia, and Pulmonata); earliest tooth formation in four species of Polyplacophora; and the morphology of the feeding apparatus in W. corrugata. The existence of a true radula membrane and of membranoblasts and odontoblasts in neomenioids indicates that morphogenesis of the aplacophoran radula is homologous to that in other radulate Mollusca. We conclude from p redness of salivary gland ducts, a divided radular sac, and a pair of anteroventral pockets that the plesiomorphic state in neomenioids is bipartite, formed of denticulate bars that are distichous (two teeth per row) on a partially divided or fused radula membrane with the largest denticles lateral, as occurs in the genus Helicoradomenia. The tooth morphology in Helicoradomenia is similar to the feeding apparatus in W. corrugata. We show that distichy also occurs during early development in several species of gastropods and polyplacophorans. Through the rejection of the null hypothesis that the earliest radula was unipartite and had no radula membrane, we conclude that the original molluscan radula was similar to the radula found in Helicoradomena species. PMID:12833382

  4. Cytogenetic characterisation of the razor shells Ensis directus (Conrad, 1843) and E. minor (Chenu, 1843) (Mollusca: Bivalvia)

    NASA Astrophysics Data System (ADS)

    González-Tizón, Ana M.; Rojo, Verónica; Vierna, Joaquín; Jensen, K. Thomas; Egea, Emilie; Martínez-Lage, Andrés

    2013-03-01

    The European razor shell Ensis minor (Chenu 1843) and the American E. directus (Conrad 1843) have a diploid chromosome number of 38 and remarkable differences in their karyotypes: E. minor has four metacentric, one metacentric-submetacentric, five submetacentric, one subtelocentric and eight telocentric chromosome pairs, whereas E. directus has three metacentric, two metacentric-submetacentric, six submetacentric, six subtelocentric and two telocentric pairs. Fluorescent in situ hybridisation (FISH) using a major ribosomal DNA probe located the major ribosomal genes on one submetacentric chromosome pair in both species; FISH with a 5S ribosomal DNA (5S rDNA) probe rendered one chromosomal (weak) signal for E. minor and no signal for E. directus, supporting a more dispersed organisation of 5S rDNA compared to the major ribosomal genes. The vertebrate telomeric sequence (TTAGGG) n was located on both ends of each chromosome, and no interstitial signals were detected. In this work, a comparative karyological analysis was also performed between the four Ensis species analysed revealing that the three European species studied so far, namely E. minor, E. siliqua (Linné 1758) and E. magnus Schumacher 1817 show more similarities among them than compared to the American species E. directus. In addition, clear karyotype differences were found between the morphologically similar species E. minor and E. siliqua.

  5. Late Quaternary Paleoceanographic Changes over the Conrad Rise and off Lutzow-Holm Bay in the Indian Sector of the Southern Ocean

    NASA Astrophysics Data System (ADS)

    Ikehara, M.; Khim, B.; Nakamura, Y.; Nogi, Y.; Katsuki, K.; Suganuma, Y.; Kameo, K.; Miura, H.; Yokoyama, Y.; Kawamura, S.; Kita, S.

    2008-12-01

    The Southern Ocean plays a very important role in the global climate system on the present and geologic past. The Southern Ocean has also become a region of paleoceanographic focus because of its key role in global deep-water circulation and its potential significance for the global carbon. For example, it has been proposed that primary production was higher and utilization of preformed nutrients in surface waters was more efficient in the glacial Southern Ocean than today, effectively lowering the glacial atmospheric CO2 concentration. To resolve the causes and processes of atmospheric CO2 change, it is important to understand mechanisms and processes of sub-systems in the Antarctic Cryosphere such as a change of biological productivity, sea surface temperature, surface water frontal system, sea-ice distribution, and East Antarctic ice sheet during the glacial-interglacial climate cycle. We collected three sediment cores from the Conrad Rise (COR-1PC, 54.27°S, 39.77°E, 2864m), the Gunnerus Ridge (GUR-1MC, 66.27°S, 33.42°E, 1348m), and off Lutzow-Holm Bay (LHB-3PC, 66.00°S, 40.00°E, 4469m) in the Indian Sector of the Southern Ocean during the R/V Hakuho- maru cruise KH07-4 Leg.3. Age models of the cores were established by radiocarbon dating of planktonic foraminifera, diatom biostratigraphy and relative paleointensity curve of the geomagnetic field. At the core LHB-3PC, biogenic opal contents indicate that the marine productivity was enhanced at interglacials in the high-latitudinal Southern Ocean. Based on the bathymetric mapping, subbottom profiling, and multi-channel seismic reflection survey, a dune- like bedform (mudwave) exists on the southwest slope of the Conrad Rise. The mudwaves are about 30 m in altitude and a few hundred meters in wavelength. The wave-field is located in water depths of 2000-3200 m. Similar wavy sedimentary structures are recognized below the seafloor in the seismic profile on the Conrad Rise. Such deep-sea mudwaves have been

  6. Relationships within Cladobranchia (Gastropoda: Nudibranchia) based on RNA-Seq data: an initial investigation

    PubMed Central

    Goodheart, Jessica A.; Bazinet, Adam L.; Collins, Allen G.; Cummings, Michael P.

    2015-01-01

    Cladobranchia (Gastropoda: Nudibranchia) is a diverse (approx. 1000 species) but understudied group of sea slug molluscs. In order to fully comprehend the diversity of nudibranchs and the evolution of character traits within Cladobranchia, a solid understanding of evolutionary relationships is necessary. To date, only two direct attempts have been made to understand the evolutionary relationships within Cladobranchia, neither of which resulted in well-supported phylogenetic hypotheses. In addition to these studies, several others have addressed some of the relationships within this clade while investigating the evolutionary history of more inclusive groups (Nudibranchia and Euthyneura). However, all of the resulting phylogenetic hypotheses contain conflicting topologies within Cladobranchia. In this study, we address some of these long-standing issues regarding the evolutionary history of Cladobranchia using RNA-Seq data (transcriptomes). We sequenced 16 transcriptomes and combined these with four transcriptomes from the NCBI Sequence Read Archive. Transcript assembly using Trinity and orthology determination using HaMStR yielded 839 orthologous groups for analysis. These data provide a well-supported and almost fully resolved phylogenetic hypothesis for Cladobranchia. Our results support the monophyly of Cladobranchia and the sub-clade Aeolidida, but reject the monophyly of Dendronotida. PMID:26473045

  7. With a little help from DNA barcoding: investigating the diversity of Gastropoda from the Portuguese coast

    PubMed Central

    Borges, Luísa M. S.; Hollatz, Claudia; Lobo, Jorge; Cunha, Ana M.; Vilela, Ana P.; Calado, Gonçalo; Coelho, Rita; Costa, Ana C.; Ferreira, Maria S. G.; Costa, Maria H.; Costa, Filipe O.

    2016-01-01

    The Gastropoda is one of the best studied classes of marine invertebrates. Yet, most species have been delimited based on morphology only. The application of DNA barcodes has shown to be greatly useful to help delimiting species. Therefore, sequences of the cytochrome c oxidase I gene from 108 specimens of 34 morpho-species were used to investigate the molecular diversity within the gastropods from the Portuguese coast. To the above dataset, we added available COI-5P sequences of taxonomically close species, in a total of 58 morpho-species examined. There was a good match between ours and sequences from independent studies, in public repositories. We found 32 concordant (91.4%) out of the 35 Barcode Index Numbers (BINs) generated from our sequences. The application of a ranking system to the barcodes yield over 70% with top taxonomic congruence, while 14.2% of the species barcodes had insufficient data. In the majority of the cases, there was a good concordance between morphological identification and DNA barcodes. Nonetheless, the discordance between morphological and molecular data is a reminder that even the comparatively well-known European marine gastropods can benefit from being probed using the DNA barcode approach. Discordant cases should be reviewed with more integrative studies. PMID:26876495

  8. With a little help from DNA barcoding: investigating the diversity of Gastropoda from the Portuguese coast.

    PubMed

    Borges, Luísa M S; Hollatz, Claudia; Lobo, Jorge; Cunha, Ana M; Vilela, Ana P; Calado, Gonçalo; Coelho, Rita; Costa, Ana C; Ferreira, Maria S G; Costa, Maria H; Costa, Filipe O

    2016-02-15

    The Gastropoda is one of the best studied classes of marine invertebrates. Yet, most species have been delimited based on morphology only. The application of DNA barcodes has shown to be greatly useful to help delimiting species. Therefore, sequences of the cytochrome c oxidase I gene from 108 specimens of 34 morpho-species were used to investigate the molecular diversity within the gastropods from the Portuguese coast. To the above dataset, we added available COI-5P sequences of taxonomically close species, in a total of 58 morpho-species examined. There was a good match between ours and sequences from independent studies, in public repositories. We found 32 concordant (91.4%) out of the 35 Barcode Index Numbers (BINs) generated from our sequences. The application of a ranking system to the barcodes yield over 70% with top taxonomic congruence, while 14.2% of the species barcodes had insufficient data. In the majority of the cases, there was a good concordance between morphological identification and DNA barcodes. Nonetheless, the discordance between morphological and molecular data is a reminder that even the comparatively well-known European marine gastropods can benefit from being probed using the DNA barcode approach. Discordant cases should be reviewed with more integrative studies.

  9. Nanoindentations on conch shells of Gastropoda and Bivalvia molluscs reveal anisotropic evolution against external attacks.

    PubMed

    Bignardi, Cristina; Petraroli, Michele; Pugno, Nicola M

    2010-10-01

    Nanoindentation method has been used to explore, at the nanoscale, the mechanical properties of four different representative types of conch shells belonging to the two biggest classes of molluscs, Gastropoda and Bivalvia, in order to compare nanohardness and Young's modulus with respect to the microstructural anisotropic architectures. For the experimental tests a Nano Indenter XP (MTS Nano Instruments, Oak Ridge TN) has been used. The mechanical tests have been carried out on the inner and outer surfaces of the shells, as well as on their cross-section, near to the inner/outer surfaces and in the middle layer. The results confirm the three layered anisotropic architecture of the investigated conchs. On each of these 5 surfaces, 2 x 5 indentations have been performed at different maximum depth: from 250 nm to 4 microm, with a step of 250 nm, for a total of 3200 tests. The numerous observations have been analysed applying an ad hoc modification of the Weibull Statistics, suggesting a natural evolution of the shells against external attacks.

  10. 18S ribosomal DNA sequences provide insight into the phylogeny of patellogastropod limpets (Mollusca: Gastropoda).

    PubMed

    Yoon, Sook Hee; Kim, Won

    2007-02-28

    To investigate the phylogeny of Patellogastropoda, the complete 18S rDNA sequences of nine patellogastropod limpets Cymbula canescens (Gmelin, 1791), Helcion dunkeri (Krauss, 1848), Patella rustica Linnaeus, 1758, Cellana toreuma (Reeve, 1855), Cellana nigrolineata (Reeve, 1854), Nacella magellanica Gmelin, 1791, Nipponacmea concinna (Lischke, 1870), Niveotectura pallida (Gould, 1859), and Lottia dorsuosa Gould, 1859 were determined. These sequences were then analyzed along with the published 18S rDNA sequences of 35 gastropods, one bivalve, and one chiton species. Phylogenetic trees were constructed by maximum parsimony, maximum likelihood, and Bayesian inference. The results of our 18S rDNA sequence analysis strongly support the monophyly of Patellogastropoda and the existence of three subgroups. Of these, two subgroups, the Patelloidea and Acmaeoidea, are closely related, with branching patterns that can be summarized as [(Cymbula + Helcion) + Patella] and [(Nipponacmea + Lottia) + Niveotectura]. The remaining subgroup, Nacelloidea, emerges as basal and paraphyletic, while its genus Cellana is monophyletic. Our analysis also indicates that the Patellogastropoda have a sister relationship with the order Cocculiniformia within the Gastropoda. PMID:17464213

  11. Pomacea canaliculata (Mollusca, Gastropoda) in Patagonia: potential role of climatic change in its dispersion and settlement.

    PubMed

    Darrigran, G; Damborenea, C; Tambussi, A

    2011-02-01

    Pomacea canaliculata (Lamarck, 1822) (Mollusca Gastropoda) shows a large native distribution range in South America, reaching as far south as 37º S (Buenos Aires, Argentina). This species was deliberately introduced into Southeast Asia around 1980 and subsequently underwent a rapid intentional or accidental dispersal into many countries in the region. It was also introduced into North and Central America and Hawaii. In this contribution we record the presence of P. canaliculata in Patagonia, assessing the possible influence of climatic change in the new establishment of this species there. Three samplings (between September 2004 and April 2005) were carried out at 38º 58' 20.2" S-68º 11' 27.3" W. In the sampling we found two adult specimens of P. canaliculata and numerous egg clutches. Pomacea canaliculata is naturally distributed in the Plata and Amazon Basins. The southern boundary of this species has been established as the isotherms of 14 ºC and 16 ºC in Buenos Aires province, and precipitations of 900 to 600 mm/year. This study also analysed variations in annual temperature and precipitation in Patagonia. Average temperatures show an increase over the years, although not constantly. Important modifications in precipitation regime in northern Patagonia, triggered by global climatic changes, could be beneficial for the settlement of populations of P. canaliculata in this new area, where precipitation increased enough to reach values similar to those in the southernmost area of distribution of this species.

  12. Feeding clusters and olfaction in the mangrove snail Terebralia palustris (Linnaeus) (Potamididae: Gastropoda).

    PubMed

    Fratini, S; Cannicci, S; Vannini, M

    2001-07-01

    Large numbers of the snail Terebralia palustris (Linnaeus) (Potamididae; Gastropoda) are frequently observed feeding in a cluster on a single fallen mangrove leaf, yet none are present on leaves nearby. Consequently, we investigated the food-finding ability of T. palustris in a Kenyan mangrove forest using field experiments. We estimated the attractive effect of different cues and analysed the paths (video-recorded) of snails when approaching a food-related odour. This intertidal snail can potentially use both air-borne and water-borne odours to locate food. T. palustris is attracted to conspecifics feeding on leaves, while intact leaves as well as non-feeding snails are not attractive. Moreover, the guiding stimulus appears to be compounds released when the leaves are damaged.T. palustris also seems able to discriminate between different food items; it is more strongly attracted to green mangrove leaves than senescent or fallen ones or mangrove propagules, probably because green leaves release a greater amount of attractive cues.Feeding snails thus recruit more snails to feed on the same leaf. The ecological implications of this behaviour are discussed: a large number of snails on the same leaf counteracts the ability of crabs to remove the leaf being eaten by the snails. PMID:11399273

  13. Nanoindentations on conch shells of Gastropoda and Bivalvia molluscs reveal anisotropic evolution against external attacks.

    PubMed

    Bignardi, Cristina; Petraroli, Michele; Pugno, Nicola M

    2010-10-01

    Nanoindentation method has been used to explore, at the nanoscale, the mechanical properties of four different representative types of conch shells belonging to the two biggest classes of molluscs, Gastropoda and Bivalvia, in order to compare nanohardness and Young's modulus with respect to the microstructural anisotropic architectures. For the experimental tests a Nano Indenter XP (MTS Nano Instruments, Oak Ridge TN) has been used. The mechanical tests have been carried out on the inner and outer surfaces of the shells, as well as on their cross-section, near to the inner/outer surfaces and in the middle layer. The results confirm the three layered anisotropic architecture of the investigated conchs. On each of these 5 surfaces, 2 x 5 indentations have been performed at different maximum depth: from 250 nm to 4 microm, with a step of 250 nm, for a total of 3200 tests. The numerous observations have been analysed applying an ad hoc modification of the Weibull Statistics, suggesting a natural evolution of the shells against external attacks. PMID:21137746

  14. Homology and homoplasy of swimming behaviors and neural circuits in the Nudipleura (Mollusca, Gastropoda, Opisthobranchia)

    PubMed Central

    Newcomb, James M.; Sakurai, Akira; Lillvis, Joshua L.; Gunaratne, Charuni A.; Katz, Paul S.

    2012-01-01

    How neural circuit evolution relates to behavioral evolution is not well understood. Here the relationship between neural circuits and behavior is explored with respect to the swimming behaviors of the Nudipleura (Mollusca, Gastropoda, Opithobranchia). Nudipleura is a diverse monophyletic clade of sea slugs among which only a small percentage of species can swim. Swimming falls into a limited number of categories, the most prevalent of which are rhythmic left–right body flexions (LR) and rhythmic dorsal–ventral body flexions (DV). The phylogenetic distribution of these behaviors suggests a high degree of homoplasy. The central pattern generator (CPG) underlying DV swimming has been well characterized in Tritonia diomedea and in Pleurobranchaea californica. The CPG for LR swimming has been elucidated in Melibe leonina and Dendronotus iris, which are more closely related. The CPGs for the categorically distinct DV and LR swimming behaviors consist of nonoverlapping sets of homologous identified neurons, whereas the categorically similar behaviors share some homologous identified neurons, although the exact composition of neurons and synapses in the neural circuits differ. The roles played by homologous identified neurons in categorically distinct behaviors differ. However, homologous identified neurons also play different roles even in the swim CPGs of the two LR swimming species. Individual neurons can be multifunctional within a species. Some of those functions are shared across species, whereas others are not. The pattern of use and reuse of homologous neurons in various forms of swimming and other behaviors further demonstrates that the composition of neural circuits influences the evolution of behaviors. PMID:22723353

  15. The Complete Mitochondrial Genome of Galba pervia (Gastropoda: Mollusca), an Intermediate Host Snail of Fasciola spp

    PubMed Central

    Huang, Wei-Yi; Zhao, Guang-Hui; Wei, Shu-Jun; Song, Hui-Qun; Xu, Min-Jun; Lin, Rui-Qing; Zhou, Dong-Hui; Zhu, Xing-Quan

    2012-01-01

    Complete mitochondrial (mt) genomes and the gene rearrangements are increasingly used as molecular markers for investigating phylogenetic relationships. Contributing to the complete mt genomes of Gastropoda, especially Pulmonata, we determined the mt genome of the freshwater snail Galba pervia, which is an important intermediate host for Fasciola spp. in China. The complete mt genome of G. pervia is 13,768 bp in length. Its genome is circular, and consists of 37 genes, including 13 genes for proteins, 2 genes for rRNA, 22 genes for tRNA. The mt gene order of G. pervia showed novel arrangement (tRNA-His, tRNA-Gly and tRNA-Tyr change positions and directions) when compared with mt genomes of Pulmonata species sequenced to date, indicating divergence among different species within the Pulmonata. A total of 3655 amino acids were deduced to encode 13 protein genes. The most frequently used amino acid is Leu (15.05%), followed by Phe (11.24%), Ser (10.76%) and IIe (8.346%). Phylogenetic analyses using the concatenated amino acid sequences of the 13 protein-coding genes, with three different computational algorithms (maximum parsimony, maximum likelihood and Bayesian analysis), all revealed that the families Lymnaeidae and Planorbidae are closely related two snail families, consistent with previous classifications based on morphological and molecular studies. The complete mt genome sequence of G. pervia showed a novel gene arrangement and it represents the first sequenced high quality mt genome of the family Lymnaeidae. These novel mtDNA data provide additional genetic markers for studying the epidemiology, population genetics and phylogeographics of freshwater snails, as well as for understanding interplay between the intermediate snail hosts and the intra-mollusca stages of Fasciola spp.. PMID:22844544

  16. Volutidae (Mollusca: Gastropoda) of the Lakhra Formation (Earliest Eocene, Sindh, Pakistan): systematics, biostratigraphy and paleobiogeography.

    PubMed

    Merle, Didier; Pacaud, Jean-Michel; Métais, Grégoire; Bartolini, Annachiara; Lashari, Rafiq A; Brohi, Imdad A; Solangi, Sarfraz H; Marivaux, Laurent; Welcomme, Jean-Loup

    2014-06-27

    The paleobiodiversity of the Volutidae (Mollusca: Gastropoda) of the Ranikot Group (Sindh, Pakistan) and particularly of the Lakhra Formation (SBZ 5 biozone, Earliest Eocene), is reconsidered on the basis of new material collected during recent field trips. Ten new species are described (Mitreola brohii sp. nov., Lyrischapa vredenburgi sp. nov., L. brevispira sp. nov., Athleta (Volutopupa) citharopsis sp. nov., A. (Volutocorbis) lasharii sp. nov., Volutilithes welcommei sp. nov., V. sindhiensis sp. nov., Pseudaulicina coxi sp. nov., Sindhiluta lakhraensis sp. nov. and Pakiluta solangii sp. nov.) and one species is in open nomenclature (Lyria sp.). Three new genera are described: Lyriopsis gen. nov. [Volutinae, ?Lyriini, type species: Lyriopsis cossmanni (Vredenburg, 1923)], Sindhiluta gen. nov. [Volutilithinae, type species: Sindhiluta lakhraensis n. sp.] and Pakiluta gen. nov. [?Volutodermatinae, type species: Pakiluta solangii n. sp.]. Two new combinations are proposed: Lyriopsis cossmanni (Vredenburg, 1923) comb. nov. and Athleta (Volutopupa) intercrenatus (Cossmann & Pissarro, 1909) comb. nov. Lectotypes are designated for Lyria cossmanni Vredenburg, 1923, L. feddeni Vredenburg, 1923, Volutospina noetlingi Cossmann & Pissarro, 1909, V. intercrenata Cossmann & Pissarro, 1909 and Athleta (Volutocorbis) victoriae Vredenburg, 1923. With 21 species, this volutid fauna is the most diverse recorded from the Tethys Ocean during Earliest Eocene time. The assemblage is characterized by a strong turnover marked by regional speciation and the appearance of many western Tethyan invaders. Although at the species level, the assemblage documents a strong provincialism, at the genus level, the high number of shared genera between Eastern Tethyan and Old World Tethyan realms begins a phase of long-term homogeneity of volutid assemblages from the Tethyan paleobiogeographic province.

  17. Gastropoda-Bivalvia Fauna And Neogene-Quaternary Stratigraphy of the Southwest of Dardanelles (Çanakkale-NWAnatolia)

    NASA Astrophysics Data System (ADS)

    Kapan, Sevinç; Kabasakal, Sinem

    2016-04-01

    Gastropoda-Bivalvia Fauna And Neogene-Quaternary Stratigraphy of the Southwest of Dardanelles (Çanakkale-NWAnatolia) Sevinç KAPAN, Sinem KABASAKAL, Çanakkale Onsekiz Mart University, Engineering Faculty, Geological Engineering Department sevinckapan_yesilyurt@hotmail.com In this study, paleontology and stratigraphy of Neogene and Quaternary units around south of the Dardanelles have been examined using Gastropoda and Bivalvia fauna. In the investigation area, the base of the sediments that belongs to Neogene, consist of the volcanics which are formed with basalts, andesites and tuff. Neogene begins unconformity with basal conglomerate which are formed with basalt and tuff gravels. The measurable thickness of the Neogene sediments is approximately 200meters in total. First fossiliferius level which consist of Lymnocardium (Euxinicardium) nobile Sabba has showed similarities with the Pontian (Late Miocene) fauna of the Eastern Paratethys. The existence of Melanopsis and Psidium species indicate that the basin has been brackish water feeding by fresh water in the Early Pliocene. Theodoxus fluviatilis (Linne), Theodoxus (Calvertia) aff. imbricata Brusina, Theodoxus (Calvertia) licherdopoli scriptus (Stefanescu), Viviparus mammatus (Stefanescu), Valvata (Valavata) sulekiana Brusina, Valvata (Cincinna) crusitensis Fontannes, Hydrobia cf grandis Cobalcescu, Hydrobia ventrosa Monfort, Melanopsis (Melanopsis) cf. bergeroni Stefanescu, , Melanopsis (Melanopsis) sandbergeri rumana Tournouer, Melanopsis (Canthidomus) hybostoma anili Taner, Melanopsis (Canthidomus) hybostoma amaradica Fontannes, Melanopsis (Canthidomus) lanceolata Neumayr, Amphimelania fossariformis (Tournouer), Melanoides tuberculata monolithica (Bukowski), Radix (Radix) peregra (Müller), Planorbarius thiollierei (Michaud), Potamida (Potamida) craiovensis craiovensis (Tournouer), Potamida (Potamida) berbestiensis (Fontannes), Unio pristinus davilai Porumbaru, Unio subexquisitus Jatzko, Anadonta zmaji

  18. Comparison of broad band time series recorded parallel by FGI type interferometric water level and Lippmann type pendulum tilt meters at Conrad observatory, Austria

    NASA Astrophysics Data System (ADS)

    Ruotsalainen, Hannu; Papp, Gabor; Leonhardt, Roman; Ban, Dora; Szücs, Eszter; Benedek, Judith

    2016-04-01

    The Finnish Geodetic Institute (FGI) the progenitor of Finnish Geospatial Research Institute of NLS designed and built a 5.5m long prototype of interferometric water level tiltmeter (iWT) in early 2014. Geodetic and Geophysical Institute (GGI), Sopron, Hungary bought the instrument and started tilt measurement in August 2014 at the Conrad observatory (COBS), Austria to monitor geodynamical phenomena like microseisms, free oscillations of the Earth, earth tides, mass loading effects and crustal deformations in cooperation with Austrian Central Institute for Meteorology and Geodynamics (ZAMG) and the FGI. On the July 16 2015 a Lippmann-type 2D tilt sensor (LTS) was also installed by GGI on the 6 m long pier where iWT was set up previously. This situation opens a possibility to do broad band (from secular to seismic variations up to 15 Hz) geophysical signal analysis comparing the responses of long (several meters) and short (a few decimeters) base instruments implementing different physical principles (relative height change of a level surface and inclination change of the plumb line). The characteristics of the sensors are studied by the evaluation of the spectra of recorded signals dominated by microseisms. The iWT has internal interferometric calibration and it can be compared to Lippmanns tilt meter one. Both instruments show good long term ( > 1 day) stability when earth tides and ocean and air mass loading tilts are modelled.

  19. Phylogenetic relationships among Opisthobranchia (Mollusca: Gastropoda) based on mitochondrial cox 1, trnV, and rrnL genes.

    PubMed

    Grande, Cristina; Templado, Josè; Cervera, J Lucas; Zardoya, Rafael

    2004-11-01

    We reconstructed the phylogenetic relationships among 37 species representing seven main lineages within Opisthobranchia (Mollusca: Gastropoda) based on a mitochondrial fragment that included partial cox 1, complete trnV, and partial rrnL genes (about 2500 bp). Phylogenetic analyses confirmed tentatively that all studied main opisthobranch lineages conformed monophyletic groups except Nudibranchia. The sacoglossan Ascobulla was placed as the most basal lineage of opisthobranchs. The basommatophoran pulmonate Siphonaria was recovered within Opisthobranchia between Ascobulla and the remaining opisthobranchs. The latter were divided into two different lineages that await formal description: on one side, Cephalaspidea, Tylodinoidea, and Anaspidea (sharing features in the reproductive, digestive, and circulatory systems) were grouped together and, on the other Architectibranchia and Nudipleura (sharing similarities in the circulatory system) were recovered as sister group taxa. Two well-supported clades were recovered within Nudipleura: Pleuroanthobranchia (new taxon) and Cladobranchia. Pleuroanthobranchia (Pleurobranchoidea plus Anthobranchia) was defined by the presence of blood gland, the presence of calcareous spicules in the integument and the presence of a caecum with an opening directly into the stomach. The new molecular phylogeny provided a robust framework for comparative studies, and prompted a revision of the morphological synapomorphies diagnosing the main clades within opisthobranchs.

  20. Biochemical profile of Achatina fulica (Mollusca: Gastropoda) after infection by different parasitic loads of Angiostrongylus cantonensis (Nematoda, Metastrongylidae).

    PubMed

    Tunholi-Alves, Vinícius Menezes; Tunholi, Victor Menezes; Amaral, Ludimila Santos; Mota, Esther Maria; Maldonado Júnior, Arnaldo; Pinheiro, Jairo; Garcia, Juberlan

    2015-01-01

    The effect of experimental infection by different parasitic loads of Angiostrongylus cantonensis (Nematode, Metastrongylidae) on the activities of the aminotransferases and concentration of total proteins, uric acid and urea in the hemolymph of Achatina fulica (Mollusca, Gastropoda) were investigated. There was a significant decrease in the concentration of total proteins in the exposed snails to 5000 or more larvae. This change was accompanied by an increase in the concentrations of urea and uric acid in the hemolymph, suggesting a higher rate of deamination of the amino acids. Besides this, variations in the activities of the aminotransferases were also observed, with the highest values recorded in the groups exposed to greater parasite load. These results suggest an increase in the use of total proteins, since there was increased formation of nitrogenous catabolites, in conformity with an increase in the aminotransferase activities. Infection was verified by the fact that L3 larvae recovered from the snails was proportion to the exposure dose of L1 larvae. Histopathological results also indicated presence of an inflammatory cell infiltrate, favoring an increase of both transaminases.

  1. Assessing metal contamination from construction and demolition (C&D) waste used to infill wetlands: using Deroceras reticulatum (Mollusca: Gastropoda).

    PubMed

    Staunton, John A; Mc Donnell, Rory J; Gormally, Michael J; Williams, Chris D; Henry, Tiernan; Morrison, Liam

    2014-11-01

    Large quantities of construction and demolition waste (C&D) are produced globally every year, with little known about potential environmental impacts. In the present study, the slug, Deroceras reticulatum (Mollusca: Gastropoda) was used as the first biomonitor of metals (Ag, As, Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Sb, Se, Ti, Tl, V and Zn) on wetlands post infilling with construction and demolition (C&D) waste. The bioaccumulation of As, Ba, Cd, Co, Sb, Se and Tl were found to be significantly elevated in slugs collected on C&D waste when compared to unimproved pastures (control sites), while Mo, Se and Sr had significantly higher concentrations in slugs collected on C&D waste when compared to known contaminated sites (mining locations), indicating the potential hazardous nature of C&D waste to biota. Identifying exact sources for these metals within the waste can be problematic, due to its heterogenic nature. Biomonitors are a useful tool for future monitoring and impact studies, facilitating policy makers and regulations in other countries regarding C&D waste infill. In addition, improving separation of C&D waste to allow increased reuse and recycling is likely to be effective in reducing the volume of waste being used as infill, subsequently decreasing potential metal contamination.

  2. The mitochondrial genome of Ifremeria nautilei and the phylogenetic position of the enigmatic deep-sea Abyssochrysoidea (Mollusca: Gastropoda).

    PubMed

    Osca, David; Templado, José; Zardoya, Rafael

    2014-09-01

    The complete nucleotide sequence of the mitochondrial (mt) genome of the deep-sea vent snail Ifremeria nautilei (Gastropoda: Abyssochrysoidea) was determined. The double stranded circular molecule is 15,664 pb in length and encodes for the typical 37 metazoan mitochondrial genes. The gene arrangement of the Ifremeria mt genome is most similar to genome organization of caenogastropods and differs only on the relative position of the trnW gene. The deduced amino acid sequences of the mt protein coding genes of Ifremeria mt genome were aligned with orthologous sequences from representatives of the main lineages of gastropods and phylogenetic relationships were inferred. The reconstructed phylogeny supports that Ifremeria belongs to Caenogastropoda and that it is closely related to hypsogastropod superfamilies. Results were compared with a reconstructed nuclear-based phylogeny. Moreover, a relaxed molecular-clock timetree calibrated with fossils dated the divergence of Abyssochrysoidea in the Late Jurassic-Early Cretaceous indicating a relatively modern colonization of deep-sea environments by these snails.

  3. Nyctemeral variations of magnesium intake in the calcitic layer of a Chilean mollusk shell ( Concholepas concholepas, Gastropoda)

    NASA Astrophysics Data System (ADS)

    Lazareth, Claire E.; Guzman, Nury; Poitrasson, Franck; Candaudap, Frederic; Ortlieb, Luc

    2007-11-01

    Mollusk shells are increasingly used as records of past environmental conditions, particularly for sea-surface temperature (SST) reconstructions. Many recent studies tackled SST (and/or sea-surface salinity) tracers through variations in the elementary (Mg and Sr) or stable isotope (δ 18O) composition within mollusk shells. But such attempts, which sometimes include calibration studies on modern specimens, are not always conclusive. We present here a series of Mg and Sr analyses in the calcitic layer of Concholepas concholepas (Muricidae, Gastropoda) with a very high time-resolution on a time window covering about 1 and a half month of shell formation, performed by Laser Ablation Inductively-Coupled Plasma Mass Spectrometry (LA-ICP-MS) and electron probe micro-analysis (EPMA). The selected specimen of this common Chilean gastropod was grown under controlled environmental conditions and precise weekly time-marks were imprinted in the shell with calcein staining. Strontium variations in the shell are too limited to be interpreted in terms of environmental parameter changes. In contrast, Mg incorporation into the shell and growth rate appear to change systematically between night and day. During the day, Mg is incorporated at a higher rate than at night and this intake seems positively correlated with water temperature. The nightly reduced Mg incorporation is seemingly related to metabolically controlled processes, formation of organic-rich shell increments and nocturnal feeding activity of the animals. The nyctemeral Mg changes in the C. concholepas shell revealed in this study might explain at least part of the discrepancies observed in previous studies on the use of Mg as a SST proxy in mollusk shells. In the case of C. concholepas, Mg cannot be used straightforwardly as a SST proxy.

  4. Occurrence and effects of organotins on adult common whelk (Buccinum undatum) (Mollusca, Gastropoda) in harbours and in a simulated dredging situation.

    PubMed

    Svavarsson, J; Granmo, A; Ekelund, R; Szpunar, J

    2001-05-01

    Transplanted common whelk (Buccinum undatum) (Mollusca, Gastropoda) accumulated fairly high levels of organotins (tributyltin (TBT) and triphenyltin (TPT)) during exposure in three harbours with different TBT contamination. This did not though lead to an increase in imposex frequency in the adult females studied. Simulating harbour dredging in an experiment using suspended sediment from one of the harbours only resulted in a low concentration of TBT in the tissues of the common whelk and subsequently no changes in the occurrence and degree of imposex. The common whelk seemed to receive the main part of TBT from the water column and the limited bioaccumulation in the experiment indicates that desorption of TBT from the suspended sediment was slow. After TBT has been totally banned, dredging of contaminated sediments will cause increased exposure of the biota to TBT. Due to slow desorption the increase may however, be slight and temporary to pelagic and epibenthic species unless the settled particles are resuspended.

  5. Taxonomic review of tropical western Atlantic shallow water Drilliidae (Mollusca: Gastropoda: Conoidea) including descriptions of 100 new species.

    PubMed

    Fallon, Phillip J Jr

    2016-01-01

    A review of the literature and examination of over 3,200 specimens of shallow water (<200 m) tropical western Atlantic (TWA) Drilliidae Olson, 1964 in museum and private collections has resulted in the recognition of numerous previously undescribed species, 100 of which are proposed here for the first time. A total of 65 names were found in the literature. Of these, 48 are considered valid, 16 synonyms, and one nomen dubium. In addition, characteristics that distinguish each genus currently in use for TWA shallow water species have indicated the need for reassignment (new combinations within Drilliidae) of 15 species. Some nomenclatural actions have come about from the literature review and include one taxon placed in junior synonymy (under an older name recently re-discovered) and one new name for a junior homonym. Two neotypes, five lectotype designations, and one new name are also proposed. Altogether, nomenclatural actions on 17% of valid previously described taxa are proposed. The 100 proposed names are placed in 12 available and one new genus: Agladrillia Woodring, 1928 (2), Bellaspira Conrad, 1868 (7), Calliclava McLean, 1971 (3), Cerodrillia Bartsch & Rehder, 1939 (11), Clathrodrillia Dall, 1918 (6), Decoradrillia, new genus (4), Douglassia Bartsch, 1934 (4), Fenimorea Bartsch, 1934 (15), Leptadrillia Woodring, 1928 (12), Lissodrillia Bartsch & Rehder, 1939 (8), Neodrillia Bartsch, 1943 (2), Splendrillia Hedley, 1922 (13), and Syntomodrillia Woodring, 1928 (13). These are the first reports of Calliclava in the western Atlantic, previously known only from the eastern Pacific. The new genus, Decoradrillia, is proposed to hold four new species and one existing that share a unique shell microsculpture and other morphological traits. One genus, Drillia Gray, 1838, is not currently believed to have TWA representatives. Three genera comprised exclusively of bathyal species are not treated in this work: Clavus Monfort, 1810 (=Eldridgea Bartsch, 1934), Globidrillia

  6. Taxonomic review of tropical western Atlantic shallow water Drilliidae (Mollusca: Gastropoda: Conoidea) including descriptions of 100 new species.

    PubMed

    Fallon, Phillip J Jr

    2016-01-01

    A review of the literature and examination of over 3,200 specimens of shallow water (<200 m) tropical western Atlantic (TWA) Drilliidae Olson, 1964 in museum and private collections has resulted in the recognition of numerous previously undescribed species, 100 of which are proposed here for the first time. A total of 65 names were found in the literature. Of these, 48 are considered valid, 16 synonyms, and one nomen dubium. In addition, characteristics that distinguish each genus currently in use for TWA shallow water species have indicated the need for reassignment (new combinations within Drilliidae) of 15 species. Some nomenclatural actions have come about from the literature review and include one taxon placed in junior synonymy (under an older name recently re-discovered) and one new name for a junior homonym. Two neotypes, five lectotype designations, and one new name are also proposed. Altogether, nomenclatural actions on 17% of valid previously described taxa are proposed. The 100 proposed names are placed in 12 available and one new genus: Agladrillia Woodring, 1928 (2), Bellaspira Conrad, 1868 (7), Calliclava McLean, 1971 (3), Cerodrillia Bartsch & Rehder, 1939 (11), Clathrodrillia Dall, 1918 (6), Decoradrillia, new genus (4), Douglassia Bartsch, 1934 (4), Fenimorea Bartsch, 1934 (15), Leptadrillia Woodring, 1928 (12), Lissodrillia Bartsch & Rehder, 1939 (8), Neodrillia Bartsch, 1943 (2), Splendrillia Hedley, 1922 (13), and Syntomodrillia Woodring, 1928 (13). These are the first reports of Calliclava in the western Atlantic, previously known only from the eastern Pacific. The new genus, Decoradrillia, is proposed to hold four new species and one existing that share a unique shell microsculpture and other morphological traits. One genus, Drillia Gray, 1838, is not currently believed to have TWA representatives. Three genera comprised exclusively of bathyal species are not treated in this work: Clavus Monfort, 1810 (=Eldridgea Bartsch, 1934), Globidrillia

  7. Developmental Phases of the Seminal Vesicle related to the Spermatogenic Stages in the Testicular Lobules of Neptunea (Barbitonia) cumingii (Gastropoda: Buccinidae)

    PubMed Central

    Kim, Sung Han

    2016-01-01

    Cytological changes of the epithelial cells according to the developmenatal phases of the seminal vesicle related to the spermatogenic stages in the testicular lobules during spermagenesis in male Neptunea (Barbitonia) cumingii (Gastropoda: Buccinidae) were investigated monthly by electron microscopical and histological observations. N. (B) cumingii is dioecious, and an internal fertilization species. The male genital organ is located near the tentacles. The spermatozoon is approximatley 50 μm in length. The axoneme of the tail flagellum consists of nine pairs of microtubles at the periphery and one pair at the center. The process of germ cell development during spermatogenesis can be divided into five succesive stages: (1) spermatogonia, (2) primary spermatocytes, (3) secondary spermatocytes, (4) spermatids, and (5) spermatozoa. A considerable amount of spermatozoa make their appearance in the testicular lobules (or acini) and some of them are tranported from the testis towards the seminal vesicles until late July. In this study, the developmental phases of the epithelial cells of the seminal vesicles of N. (B.) cumingii could be classified into four phases: (1) S-I phase (resting), (2) S-Ⅱphase (early accumulating), (3) S-Ⅲ phase (accumulating), and (4) S-IV phase (spent). However, in case of N. (B.) arthritica cumingii, the developmental phases of the seminal vesicle were devided into three phases: (1) resting, (2) accumulating and (3) spent. Granular bodies in the inner layer of the seminal vesicles are involved in resorption of digestion of residual spermatozoa. PMID:27796006

  8. [Space-time variation of Scleractinia, Gorgonacea, Gastropoda, Bivalvia, Cephalopoda, Asteroidea, Echinoidea and Holothuroidea, from shallow bottom in San Jose Island, Gulf of California].

    PubMed

    Holguin Quiñones, Oscar Efraín; González Medina, Felipe de Jesús; Solís Marín, Francisco; Félix Pico, Esteban F

    2008-09-01

    Between the years 1999 and 2000, six expeditions were made to Isla San José, in the Gulf of California. Observations and samples were taken of benthic macroinvertebrates in nine locations. Based on the samples, the specific components of three phyla were determined: Cnidaria (Scleractinia and Gorgonacea), Mollusca (Gastropoda, Bivalvia and Cephalopoda), and Echinodermata (Echinoidea and Holothuroidea). The abundance of conspicuous benthic macroinvertebrates was visually estimated through free dives at a depth of between two and six meters along two transects parallel to the coast. A total of 38 taxa in three groups were determined. The most abundant species are Tripneustes depressus (44.9%), Echinometra vanbruntii (18.3%), Phataria unifascialis (8.9%), Centrostephanus coronatus (8.0%), Diadema mexicanum (5%) y Eucidaris thouarsii (3.6%). No significant differences between diversity (H'), equity (J) and richness of the species (S) during the months and site of study. The similarity analysis identified two groups from locations of the eastern and western coasts. PMID:19419038

  9. Supercooling ability in two populations of the land snail Helix pomatia (Gastropoda: Helicidae) and ice-nucleating activity of gut bacteria.

    PubMed

    Nicolai, Annegret; Vernon, Philippe; Lee, Marcia; Ansart, Armelle; Charrier, Maryvonne

    2005-02-01

    The land snail Helix pomatia (Gastropoda: Helicidae) is widely distributed in Northern and Central Europe where it may experience subzero temperatures during winter months. Its supercooling ability was studied in two populations of H. pomatia. One population originated from Southern Sweden (Gotaland) and the other from Central France (Auvergne). In the experimental design, they were acclimated, over 2 weeks, to artificial winter conditions (hibernation, T=5 degrees C). The Swedish snails showed a rather limited supercooling ability (temperature of crystallization, T(c)=-6.4+/-0.8 degrees C), significantly greater, however, than the supercooling capacity of the population from France (T(c)=-4.6+/-1.4 degrees C). In artificial spring conditions (3 months of hibernation followed by a progressive acclimation, over 2 weeks, to activity at T=20 degrees C), both populations exhibited a similar high T(c) (-2.0+/-1.0 degrees C). The lower T(c) of hibernating Swedish snails could be due to a greater loss of body water, accompanied by a higher concentration of solutes in the hemolymph. In both populations, the variation in hemolymph osmolality measured between hibernating (250-270 mOsm kg(-1)) and active (165-215 mOsm kg(-1)) snails may be explained by the variation in body water mass and did not suggest the production of colligative cryoprotectants. Moreover, the three bacterial strains, Buttiauxella sp., Kluyvera sp., and Tatumella sp. (Enterobacteriaceae) which were isolated from fed snails, but absent in starved snails, did not show any ice-nucleating activity at temperatures higher than -9 degrees C. Only the strain Kluyvera sp. initiated nucleation at -9 degrees C. This strain, therefore, is a weak, also termed a Type III or Class C ice-nucleating active bacterium, but with no influence on the supercooling ability of individual snails. In summary, fluctuations in body water mass of hibernating snail populations, triggering changes in osmolyte concentration, rather than

  10. Supercooling ability in two populations of the land snail Helix pomatia (Gastropoda: Helicidae) and ice-nucleating activity of gut bacteria.

    PubMed

    Nicolai, Annegret; Vernon, Philippe; Lee, Marcia; Ansart, Armelle; Charrier, Maryvonne

    2005-02-01

    The land snail Helix pomatia (Gastropoda: Helicidae) is widely distributed in Northern and Central Europe where it may experience subzero temperatures during winter months. Its supercooling ability was studied in two populations of H. pomatia. One population originated from Southern Sweden (Gotaland) and the other from Central France (Auvergne). In the experimental design, they were acclimated, over 2 weeks, to artificial winter conditions (hibernation, T=5 degrees C). The Swedish snails showed a rather limited supercooling ability (temperature of crystallization, T(c)=-6.4+/-0.8 degrees C), significantly greater, however, than the supercooling capacity of the population from France (T(c)=-4.6+/-1.4 degrees C). In artificial spring conditions (3 months of hibernation followed by a progressive acclimation, over 2 weeks, to activity at T=20 degrees C), both populations exhibited a similar high T(c) (-2.0+/-1.0 degrees C). The lower T(c) of hibernating Swedish snails could be due to a greater loss of body water, accompanied by a higher concentration of solutes in the hemolymph. In both populations, the variation in hemolymph osmolality measured between hibernating (250-270 mOsm kg(-1)) and active (165-215 mOsm kg(-1)) snails may be explained by the variation in body water mass and did not suggest the production of colligative cryoprotectants. Moreover, the three bacterial strains, Buttiauxella sp., Kluyvera sp., and Tatumella sp. (Enterobacteriaceae) which were isolated from fed snails, but absent in starved snails, did not show any ice-nucleating activity at temperatures higher than -9 degrees C. Only the strain Kluyvera sp. initiated nucleation at -9 degrees C. This strain, therefore, is a weak, also termed a Type III or Class C ice-nucleating active bacterium, but with no influence on the supercooling ability of individual snails. In summary, fluctuations in body water mass of hibernating snail populations, triggering changes in osmolyte concentration, rather than

  11. Evolution of gastropod mitochondrial genome arrangements

    PubMed Central

    2008-01-01

    (polyphyletic) nor Opisthobranchia (because of the inclusion S. pectinata) were recovered as monophyletic groups. The gene order of the Vetigastropoda might represent the ancestral mitochondrial gene order for Gastropoda and we propose that at least three major rearrangements have taken place in the evolution of gastropods: one in the ancestor of Caenogastropoda, another in the ancestor of Patellogastropoda, and one more in the ancestor of Heterobranchia. PMID:18302768

  12. Assessing divergence time of Spirulida and Sepiida (Cephalopoda) based on hemocyanin sequences.

    PubMed

    Warnke, Kerstin Martina; Meyer, Achim; Ebner, Bettina; Lieb, Bernhard

    2011-02-01

    The phylogenetic position of the mesopelagic decabrachian cephalopod Spirula is still a matter of debate. Since hemocyanin has successfully been used to calibrate a molecular clock for many molluscan species, a molecular clock was calculated based on this gene with special attention to the cephalopod genera Spirula and Sepia. The obtained partial sequence comprising ca., one third (3567 bp) of the complete gene is similar to that of Sepia officinalis. The molecular clock was calibrated using the splits of Gastropoda-Cephalopoda (ca. 550 ± 50 mya) and Heterobranchia-Vetigastropoda (ca. 380 ± 10 mya). The resulting hemocyanin-based molecular clock is stable, and the estimated divergence time of Spirulida and Sepiida, some 150 ± 30 million years ago, can be deemed reliable.

  13. Mollusks (Gastropoda and Bivalvia) of the Multiple-Use Reserve Martín García Island, Río de la Plata River: biodiversity and ecology.

    PubMed

    César, I I; Martín, S M; Rumi, A; Tassara, M

    2012-02-01

    The Island of Martin Garcia is located in the Upper Río de la Plata, to the south of mouth the Uruguay River. The aim of the present study was to analyse the biodiversity of the island freshwater mollusks and their relationships to environmental variables. Twelve sampling sites were selected, five were along the littoral section of the island and seven were Inland ponds. Seven major environmental variables were measured: water and air temperature, percentage of oxygen saturation, dissolved oxygen, electrical conductivity, total dissolved solids and pH. Twenty-seven mollusk species were found, Antillorbis nordestensis, Biomphalaria tenagophila tenagophila , B. t. guaibensis, B. straminea, B. peregrina, Drepanotrema kermatoides, D. cimex, D. depressissimum, Chilina fluminea, C. rushii, C. megastoma, Uncancylus concentricus, Hebetancylus moricandi, Stenophysa marmorata, Heleobia piscium, H. parchappii, Potamolithus agapetus, P. buschii, P. lapidum, Pomacea canaliculata, P. megastoma, Asolene platae, Corbicula fluminea, Eupera platensis, Pisidium sterkianum, P. taraguyense and Limnoperna fortunei. UPGMA clustering of species based on their occurrence in different ecological conditions revealed two main species groups. The Canonical Correspondence Analysis suggests that the species distribution is related to the physico-chemical condition of water. Axis two of the ordination diagram displayed the approximately 95.6% of the correlation between species and environmental variables. Dissolved oxygen, conductivity, water temperature and pH showed the highest fluctuations during the sampling period. The species richness (S) showed relationships mainly with water temperature and conductivity. The biodiversity of the gastropods and bivalves from Martín García Island amounts to up to 26 species. Among the Gastropoda, the Planorbidae family made the most sizeable contribution. The Lithogliphidae P. agapetus (26.28%) and P. buschii (9.50%) showed the highest relative

  14. Pleurotomarioidean gastropods.

    PubMed

    Harasewych, M G

    2002-01-01

    Pleurotomarioidean gastropods are continuously present in the fossil record since the Upper Cambrian and survive into the Recent fauna, thus providing rare insights into the evolutionary history of the class Gastropoda. Pleurotomarioidea achieved greatest numerical and morphological diversity during the Paleozoic, and dominated global shallow water marine gastropod faunas during the Paleozoic and Mesozoic. Only a single family, the Pleurotomariidae, survived the end-Cretaceous Extinction, but was restricted to deep water through most of the Cenozoic. The first living pleurotomariid was discovered during the mid-nineteenth century, along the bathyal zone of the western Atlantic. Subsequently collected specimens of these "living fossils" revealed that these animals comprise a mosaic of primitive and highly derived characters that originally inspired a new model of gastropod evolution, but more recently defy the orderly inclusion of this group within a cladistic framework of gastropod phylogeny. Molecular studies have likewise shown that the 18S rDNA gene of pleurotomariids contains novel insertions, and evolves more rapidly than in related taxa. A number of studies confirm that the Pleurotomarioidea may be included in the clade Vetigastropoda together with the Trochoidea, Fissurelloidea, Haliotoidea, and Scissurelloidea. However, neither the position of the superfamily within Vetigastropoda, nor the position of Vetigastropoda within Gastropoda is yet robustly resolved. The anatomical and molecular data are reviewed; the latter used to produce a well-resolved phylogeny of the genera within the family, and to justify the naming of the long-used informal grouping "Perotrochus Group B" as the genus Bayerotrochus. A review of the geographic and bathymetric distributions of pleurotomariids reveals that the higher taxa segregate bathymetrically, while the species within each genus generally segregate geographically, so that most species exist in allopartry. The diet of

  15. An annotated catalogue and bibliography of the taxonomy, synonymy and distribution of the Recent Vetigastropoda of South Africa (Mollusca).

    PubMed

    Herbert, David G

    2015-11-30

    A complete inventory of the known Recent vetigastropod fauna of South Africa is provided. Bibliographic citations to works discussing the taxonomy, synonymy and distribution of the species in a southern African or south-western Indian Ocean context are provided. Additional explanatory notes are given where pertinent. New genus records for South Africa: Acremodontina B.A. Marshall, 1995; Choristella Bush, 1879; Cocculinella Thiele, 1909; Conjectura Finlay, 1926; Crosseola Iredale, 1924; Falsimargarita Powell, 1951; Lepetella Verrill, 1880; Profundisepta McLean & Geiger, 1998; Stomatella Lamarck, 1816; Stomatia Helbling, 1779; Stomatolina Iredale, 1937; Synaptocochlea Pilsbry, 1890; Tibatrochus Nomura, 1940; Visayaseguenzia Poppe, Tagaro & Dekker, 2006; Zetela Finlay, 1926. New species records for South Africa: Acremodontina aff. carinata Powell, 1940; Anatoma finlayi (Powell, 1937); Anatoma munieri (P. Fischer, 1862); Calliotropis acherontis B.A. Marshall, 1979; Calliotropis bucina Vilvens, 2006; Cocculinella minutissima (E.A. Smith, 1904); Diodora ruppellii (G.B. Sowerby (I), 1835); Emarginula costulata Deshayes, 1863; Emarginula decorata Deshayes, 1863; Jujubinus hubrechti Poppe, Tagaro & Dekker, 2006; Lepetella sp.; Seguenzia orientalis Thiele, 1925; Stomatella auricula Lamarck, 1816; Stomatia phymotis Helbling, 1779; Stomatolina angulata (A. Adams, 1850); Stomatolina cf. calliostoma (A. Adams, 1850); Stomatolina aff. danblumi Singer & Mienis, 1999; Stomatolina cf. rubra (Lamarck, 1822); Stomatolina sp.; Synaptocochlea concinna (Gould, 1845); Tectus mauritianus (Gmelin, 1791); Tibatrochus cf. incertus (Schepman, 1908); Turbo imperialis Gmelin, 1791; Turbo tursicus Reeve, 1848; Visayaseguenzia compsa (Melvill, 1904).New species: Spectamen martensi, replacement name for Spectamen semisculptum sensu Herbert (1987) (non Martens, 1904). New name: Oxystele antoni is proposed as a new name for Trochus (Turbo) variegatus (non Gmelin, 1791 =Heliacus) Anton, 1838. Revised taxonomy: Cyclostrema semisculptum Martens, 1904 is an earlier name for Solariella intermissa Thiele, 1925, and is referable to the genus Zetela Finlay, 1926; Margarita bicarinata A. Adams & Reeve, 1850 is considered to be a senior synonym of Solariella undata G.B. Sowerby (II), 1870, and is referable to the genus Ilanga Herbert, 1987. Validation of the name Trochus tigrinus Chemnitz, 1781 is credited to Dillwyn (1817) rather than Anton (1838). New synonyms: Clanculus exquisita Turton, 1932 =Calliostoma africanum Bartsch, 1915; Cyclostrema alfredensis Bartsch, 1915 =Parviturbo alfredensis (Bartsch, 1915); Cynisca gloriosa Bartsch, 1915 =Cinysca spuria (Gould, 1861); Herbertina hayesi Herbert, 1995 =Bruceina chenoderma (Barnard, 1963); Ilanga millardi Herbert, 1987 =Ilanga humillima (Thiele, 1925); Leptothyra africana Bartsch, 1915 =Cinysca spuria (Gould, 1861); Leptothyra albocincta Turton, 1932 =Tricolia striolata (Turton, 1932); Solariella undata G.B. Sowerby (II), 1870, S. gratiosa Thiele, 1925 and S. valdiviae Thiele, 1925 =Ilanga bicarinata bicarinata (A. Adams & Reeve, 1850); Solariella chuni Thiele, 1925, S. intermissa Thiele, 1925, S. gilchristi Barnard, 1963 and S. macleari Barnard, 1963 =Zetela semisculpta (Martens, 1904); Turbo (Collonia) armillatus G.B. Sowerby (III), 1886 =Cinysca spuria (Gould, 1861). New combinations: Basilissa (Ancistrobasis) compsa Melvill, 1904 is transferred to Visayaseguenzia; Calcar rhysopoma Barnard, 1964 is transferred to Bothropoma; Calliostoma glaucophaos Barnard, 1963 is transferred to Falsimargarita; Calliotropis chenoderma Barnard, 1963 is transferred to Bruceina; Collonia bicarinata Martens, 1902 is transferred to Cinysca; Crossea agulhasensis Thiele, 1925 is transferred to Conjectura; Cyclostrema semisculptum Martens, 1904 is transferred to Zetela; Cyclostremella farica Bartsch, 1915 is transferred to Dikoleps; Cynisca africana Bartsch, 1915 is transferred to Homalopoma; Leptogyra africana: Bartsch, 1915 is transferred to Cirsonella; Leptothyra agulhasensis Thiele, 1925 is transferred to Homalopoma; Leptothyra alfredensis Bartsch, 1915 is transferred to Parviturbo; Leptothyra sola Barnard, 1963 is transferred to a Parviturbo; Liotia (Cynisca) semiclausa Thiele, 1925 is transferred to Cinysca; Monilea spuria Gould, 1861 is transferred to Cinysca; Monodonta gibbula Thiele, 1925 is transferred to Cantrainea; Puncturella voraginosa Herbert & Kilburn, 1986 is transferred to Profundisepta; Solariella fuscomaculata G.B. Sowerby (III), 1892 is transferred to Skenea; Solariella turbynei Barnard, 1963 is transferred to Zetela; Turbo boswellae Barnard, 1969 is transferred to Cantrainea; Turbo foveolatus Barnard, 1963 is transferred to Crosseola; Turbo ponsonbyi G.B. Sowerby (III), 1897 is transferred to Bothropoma; Vitrinella agulhasensis Thiele, 1925 is transferred to Parviturbo; Vitrinella (Docomphala) arifca Bartsch, 1915 is transferred to Lodderena; Vitrinella inclinans Barnard, 1963 is transferred to Skenea.

  16. Behavioral thermoregulation and critical thermal limits of giant keyhole limpet Megathura crenulata(Sowerby 1825) (Mollusca; Vetigastropoda).

    PubMed

    Díaz, Fernando; Denisse Re, Ana; Salas, Alfredo; Galindo-Sanchez, Clara E; Gonzalez, Marco A; Sanchez, Adolfo; Rosas, Carlos

    2015-12-01

    The thermoregulatory behavior of the giant keyhole limpet Megathura crenulata was determined in a horizontal thermal gradient during the day at 18.9 °C and 18.3 °C for the night. The final preferendum determined for giant keyhole limpets was of 18.6±1.2 °C. Limpets' displacement velocity was 10.0±3.9 cm h(-1) during the light phase and 8.4±1.6 cm h(-1) during the dark phase. The thermotolerance (measured as CTMax at 50%) was determined in a keyhole limpet in three acclimation temperatures 17, 20, and 23 °C. Limpets were subjected to water increasing temperatures at a rate of 1 °C every 30 min, until they detached from the substrate. The critical thermal maximum at 50% was 27.2, 27.9 and 28.3 °C respectively.

  17. CERT tribal internship program. Final intern report: David Conrad, 1993

    SciTech Connect

    1998-09-01

    The intern`s report contains a Master`s thesis entitled, ``An implementation analysis of the US Department of Energy`s American Indian policy as part of its environmental restoration and waste management mission.`` This thesis examines the implementation of a working relationship between the Nez Perce Tribe and the US Department of Energy`s Office of Environmental Restoration and Waste Management at the Hanford reservation. It examines the relationship using a qualitative methodology and three generations of policy analysis literature to gain a clear understanding of the potential for successful implementation.

  18. Allozyme variation in Busycon whelks (Gastropoda: Melongenidae).

    PubMed

    Berlocher, S H

    2000-10-01

    Large Busycon whelks are used in physiological research and are key predators in shallow water marine communities in eastern North America. Allozyme analysis of 16 loci in Busycon carica (knobbed whelk), B. sinistrum (left-handed or lightning whelk), and the closely related outgroup Busycotypus spiratum (pear whelk) was performed. Striking differences in within-species genetic differentiation were observed. Geographic variation in B. carica is moderate (FST = 0.051). In B. sinistrum, however, FST is 0.625, suggesting the existence of either highly distinct subspecies or unresolved species. The pattern of genetic variation in B. sinistrum may be congruent with that in other taxa that have experienced Gulf-Atlantic and eastern-western Gulf vicariance events. The data are compatible with an evolutionary rate of 0.046 Nei D/million years.

  19. Taxonomical study on the mollusks collected in Marion-Dufresne (MD55) and other expeditions to SE Brazil: the Fissurellidae (Mollusca, Vetigastropoda).

    PubMed

    Simone, Luiz Ricardo L; Cunha, Carlo M

    2014-01-01

    The Fissurellidae collected by the Marion-Dufresne Expedition, as well as other regional expeditions to SE Brazil are examined taxonomically, treating 21 species, of which 20 are new. The following new species are described (order according to depth range; species marked with * are from expeditions other than MD55): Cornisepta uirapa (790-940 m), Cornisepta arrepiata (295-1,050 m), Cornisepta aninga (295-1,050 m), Cranopsis hycavis (637 m), Cranopsis nymphalis (295 m), Cranopsis enigmatica (790-940 m), Cranopsis cearensis* (250 m), Cranopsis apostrema (110-940 m), Cranopsis alaris (250-450 m), Cranopsis canopa* (250 m), Cranopsis columbaris* (250 m), Emarginula suspira (54-940 m), Emarginula icosisculpta (10-12 m), Manganesepta atiaia (950-1,570 m), Profundisepta denudata* (3,000 m), Puncturella volcano (607-620 m), Rimula leptarcis (85-105 m), Zeidora pussa (607-940 m), Zeidora crepidula (790-940 m), Hemimarginula hemitoma (1-105 m). Diodora mirifica Métivier, 1972 (10-12 m), common in Brazilian oceanic islands, is the only fissurellid species previously known from that area. The genera Cornisepta, Cranopsis, Manganesepta, Profundisepta, Zeidora, and Hemimarginula are reported for the first time from Brazil. Emarginula suspira is named for material that has been misidentified as E. tuberculosa, a Miocene Mediterranean fossil. PMID:25081465

  20. Taxonomical study on the mollusks collected in Marion-Dufresne (MD55) and other expeditions to SE Brazil: the Fissurellidae (Mollusca, Vetigastropoda).

    PubMed

    Simone, Luiz Ricardo L; Cunha, Carlo M

    2014-07-14

    The Fissurellidae collected by the Marion-Dufresne Expedition, as well as other regional expeditions to SE Brazil are examined taxonomically, treating 21 species, of which 20 are new. The following new species are described (order according to depth range; species marked with * are from expeditions other than MD55): Cornisepta uirapa (790-940 m), Cornisepta arrepiata (295-1,050 m), Cornisepta aninga (295-1,050 m), Cranopsis hycavis (637 m), Cranopsis nymphalis (295 m), Cranopsis enigmatica (790-940 m), Cranopsis cearensis* (250 m), Cranopsis apostrema (110-940 m), Cranopsis alaris (250-450 m), Cranopsis canopa* (250 m), Cranopsis columbaris* (250 m), Emarginula suspira (54-940 m), Emarginula icosisculpta (10-12 m), Manganesepta atiaia (950-1,570 m), Profundisepta denudata* (3,000 m), Puncturella volcano (607-620 m), Rimula leptarcis (85-105 m), Zeidora pussa (607-940 m), Zeidora crepidula (790-940 m), Hemimarginula hemitoma (1-105 m). Diodora mirifica Métivier, 1972 (10-12 m), common in Brazilian oceanic islands, is the only fissurellid species previously known from that area. The genera Cornisepta, Cranopsis, Manganesepta, Profundisepta, Zeidora, and Hemimarginula are reported for the first time from Brazil. Emarginula suspira is named for material that has been misidentified as E. tuberculosa, a Miocene Mediterranean fossil.

  1. Selection of reference genes as internal controls for gene expression in tissues of red abalone Haliotis rufescens (Mollusca, Vetigastropoda; Swainson, 1822).

    PubMed

    López-Landavery, Edgar A; Portillo-López, Amelia; Gallardo-Escárate, Cristian; Del Río-Portilla, Miguel A

    2014-10-10

    The red abalone Haliotis rufescens is one of the most important species for aquaculture in Baja California, México, and despite this, few gene expression studies have been done in tissues such as gill, head and gonad. For this purpose, reverse transcription and quantitative real time PCR (RT-qPCR) is a powerful tool for gene expression evaluation. For a reliable analysis, however, it is necessary to select and validate housekeeping genes that allow proper transcription quantification. Stability of nine housekeeping genes (ACTB, BGLU, TUBB, CY, GAPDH, HPRTI, RPL5, SDHA and UBC) was evaluated in different tissues of red abalone (gill, head and gonad/digestive gland). Four-fold serial dilutions of cDNA (from 25 ngμL(-1) to 0.39 ngμL(-1)) were used to prepare the standard curve, and it showed gene efficiencies between 0.95 and 0.99, with R(2)=0.99. geNorm and NormFinder analysis showed that RPL5 and CY were the most stable genes considering all tissues, whereas in gill HPRTI and BGLU were most stable. In gonad/digestive gland, RPL5 and TUBB were the most stable genes with geNorm, while SDHA and HPRTI were the best using NormFinder. Similarly, in head the best genes were RPL5 and UBC with geNorm, and GAPDH and CY with NormFinder. The technical variability analysis with RPL5 and abalone gonad/digestive gland tissue indicated a high repeatability with a variation coefficient within groups ≤ 0.56% and between groups ≤ 1.89%. These results will help us for further research in reproduction, thermoregulation and endocrinology in red abalone.

  2. The Mitochondrial Genomes of the Nudibranch Mollusks, Melibe leonina and Tritonia diomedea, and Their Impact on Gastropod Phylogeny.

    PubMed

    Sevigny, Joseph L; Kirouac, Lauren E; Thomas, William Kelley; Ramsdell, Jordan S; Lawlor, Kayla E; Sharifi, Osman; Grewal, Simarvir; Baysdorfer, Christopher; Curr, Kenneth; Naimie, Amanda A; Okamoto, Kazufusa; Murray, James A; Newcomb, James M

    2015-01-01

    The phylogenetic relationships among certain groups of gastropods have remained unresolved in recent studies, especially in the diverse subclass Opisthobranchia, where nudibranchs have been poorly represented. Here we present the complete mitochondrial genomes of Melibe leonina and Tritonia diomedea (more recently named T. tetraquetra), two nudibranchs from the unrepresented Cladobranchia group, and report on the resulting phylogenetic analyses. Both genomes coded for the typical thirteen protein-coding genes, twenty-two transfer RNAs, and two ribosomal RNAs seen in other species. The twelve-nucleotide deletion previously reported for the cytochrome oxidase 1 gene in several other Melibe species was further clarified as three separate deletion events. These deletions were not present in any opisthobranchs examined in our study, including the newly sequenced M. leonina or T. diomedea, suggesting that these previously reported deletions may represent more recently divergent taxa. Analysis of the secondary structures for all twenty-two tRNAs of both M. leonina and T. diomedea indicated truncated d arms for the two serine tRNAs, as seen in some other heterobranchs. In addition, the serine 1 tRNA in T. diomedea contained an anticodon not yet reported in any other gastropod. For phylogenetic analysis, we used the thirteen protein-coding genes from the mitochondrial genomes of M. leonina, T. diomedea, and seventy-one other gastropods. Phylogenetic analyses were performed for both the class Gastropoda and the subclass Opisthobranchia. Both Bayesian and maximum likelihood analyses resulted in similar tree topologies. In the Opisthobranchia, the five orders represented in our study were monophyletic (Anaspidea, Cephalaspidea, Notaspidea, Nudibranchia, Sacoglossa). In Gastropoda, two of the three traditional subclasses, Opisthobranchia and Pulmonata, were not monophyletic. In contrast, four of the more recently named gastropod clades (Vetigastropoda, Neritimorpha

  3. The Mitochondrial Genomes of the Nudibranch Mollusks, Melibe leonina and Tritonia diomedea, and Their Impact on Gastropod Phylogeny

    PubMed Central

    Sevigny, Joseph L.; Kirouac, Lauren E.; Thomas, William Kelley; Ramsdell, Jordan S.; Lawlor, Kayla E.; Sharifi, Osman; Grewal, Simarvir; Baysdorfer, Christopher; Curr, Kenneth; Naimie, Amanda A.; Okamoto, Kazufusa; Murray, James A.; Newcomb, James M.

    2015-01-01

    The phylogenetic relationships among certain groups of gastropods have remained unresolved in recent studies, especially in the diverse subclass Opisthobranchia, where nudibranchs have been poorly represented. Here we present the complete mitochondrial genomes of Melibe leonina and Tritonia diomedea (more recently named T. tetraquetra), two nudibranchs from the unrepresented Cladobranchia group, and report on the resulting phylogenetic analyses. Both genomes coded for the typical thirteen protein-coding genes, twenty-two transfer RNAs, and two ribosomal RNAs seen in other species. The twelve-nucleotide deletion previously reported for the cytochrome oxidase 1 gene in several other Melibe species was further clarified as three separate deletion events. These deletions were not present in any opisthobranchs examined in our study, including the newly sequenced M. leonina or T. diomedea, suggesting that these previously reported deletions may represent more recently divergent taxa. Analysis of the secondary structures for all twenty-two tRNAs of both M. leonina and T. diomedea indicated truncated d arms for the two serine tRNAs, as seen in some other heterobranchs. In addition, the serine 1 tRNA in T. diomedea contained an anticodon not yet reported in any other gastropod. For phylogenetic analysis, we used the thirteen protein-coding genes from the mitochondrial genomes of M. leonina, T. diomedea, and seventy-one other gastropods. Phylogenetic analyses were performed for both the class Gastropoda and the subclass Opisthobranchia. Both Bayesian and maximum likelihood analyses resulted in similar tree topologies. In the Opisthobranchia, the five orders represented in our study were monophyletic (Anaspidea, Cephalaspidea, Notaspidea, Nudibranchia, Sacoglossa). In Gastropoda, two of the three traditional subclasses, Opisthobranchia and Pulmonata, were not monophyletic. In contrast, four of the more recently named gastropod clades (Vetigastropoda, Neritimorpha

  4. The Darkness of Man's Heart: Exploring the Depths of Depravity in Golding and Conrad.

    ERIC Educational Resources Information Center

    Camerota, Elaine

    1966-01-01

    A study of the fictional treatment of the same theme--man's depravity--in "Lord of the Flies" and "Heart of Darkness" provides an approach to literary study which sharpens students' analytical skills through a comparison of the books and an exploration of the uniqueness of each. Although there are differences evident between the books (e.g.,…

  5. Klaus Conrad (1905–1961): Delusional Mood, Psychosis, and Beginning Schizophrenia

    PubMed Central

    Mishara, Aaron L.

    2010-01-01

    Klaus Conrad’s major contribution to the phenomenology of psychosis focused on the patient’s experiences during the prodromal and early psychotic phases of schizophrenia. The literature in English concerning his work is sparse, in part because Conrad’s work contains complex concepts that lose much in translation. This communication attempts to clarify Conrad’s thought, especially as it pertains to the role of mood and delusions in beginning psychosis and its underlying neurobiology. PMID:19965934

  6. A Study of Ideational Metafunction in Joseph Conrad's "Heart of Darkness": A Critical Discourse Analysis

    ERIC Educational Resources Information Center

    Alaei, Mahya; Ahangari, Saeideh

    2016-01-01

    The linguistic study of literature or critical analysis of literary discourse is no different from any other textual description; it is not a new branch or a new level or a new kind of linguistics but the application of existing theories and methods (Halliday, 2002). This study intends to determine how ideology or opinion is expressed in Joseph…

  7. Theory for the Untheoretical: Rereading and Reteaching Austen, Bronte, and Conrad.

    ERIC Educational Resources Information Center

    Sullivan, Zohreh T.

    1991-01-01

    Describes how current critical literary theory has changed one teacher's approach to three canonical texts, by viewing texts as production and construction, unconsciously produced and inscribed by history, ideology, and politics. Notes that recent theory has been a liberating force allowing respect for student comments formerly deemed silly and…

  8. VizieR Online Data Catalog: Galactic open clusters in RAVE (Conrad+, 2014)

    NASA Astrophysics Data System (ADS)

    Conrad, C.; Scholz, R.-D.; Kharchenko, N. V.; Piskunov, A. E.; Schilbach, E.; Roser, S.; Boeche, C.; Kordopatis, G.; Siebert, A.; Williams, M.; Munari, U.; Matijevic, G.; Grebel, E. K.; Zwitter, T.; de Jong, R. S.; Steinmetz, M.; Gilmore, G.; Seabroke, G.; Freeman, K.; Navarro, J. F.; Parker, Q.; Reid, W.; Watson, F.; Gibson, B. K.; Bienayme, O.; Wyse, R.; Bland-Hawthorn, J.; Siviero, A.

    2014-01-01

    The presented tables summarise new radial velocities and average metallicities for Galactic open clusters extracted from the Catalogue of Open Cluster Data (COCD; Kharchenko et al. 2005, Cat. J/A+A/438/1163, J/A+A/440/403). The data were obtained from the RAdial Velocity Experiment (RAVE; Kordopatis et al. 2013AJ....146..134K) through a cross match with the stellar catalogues related to the COCD. The RV and [M/H] values were computed as weighted means, considering the individual uncertainties of the included members and their cluster membership probability based on position, proper motion, and photometry. The three uncertainties listed originate from different calculations: "RVRAVE" and "MetRAVE" are the weighted mean values for RV and [M/H] "errRV" and "errMet" are equivalent to the uncertainty of the mean values "sigRV" and "sigMet" are the standard deviations of the mean values "eRV" and "eMet" weighted mean values of the individual uncertainties of the included open cluster (OC) members For the calculations we primarily considered most probable OC members (best members) with a membership probability of at least 61%. Only in cases where just one or no most probable members was available we also included possible members (good members) with membership probabilities above 14%. In the table we include the numbers for both types of members separately: best members -> "bmem" and good members -> "gmem". We included reference values for RVs from the second version of the Catalogue of Radial Velocities with Astrometric Data (CRVAD-2) and the Catalogue of Radial Velocities of Open Clusters and Associations (CRVOCA) provided by Kharchenko et al. 2007, Cat. III/254). The CRVAD-2 reference values were computed according to the RAVE values for identified OC members. The CRVOCA references were directly extracted from the catalogue and number of OC members used are given in column "nmem". The reference values for [M/H] were obtained from the online compilation provided by Dias et al. (2002, See B/ocl), hereafter referred to as DAML. These were obtained through different techniques and the literature references from DAML are also included in our table. In DAML actual [M/H] values are mixed with [Fe/H] values and we only considered the actual [M/H], based on information given in the references. (2 data files).

  9. [Wilhelm Conrad Röntgen and the discovery of X-rays].

    PubMed

    Tubiana, M

    1996-01-01

    W.C. Röntgen reported the discovery of X-rays in December 1895 after seven weeks of assiduous work during which he had studied the properties of this new type of radiation able to go through screens of notable thickness. He named them X-rays to underline the fact that their nature was unknown. The news of this discovery immediately aroused an immense interest in the public and also initiated intense research in several directions. Physicians and physicists began as early as January 1896 to use X-rays on patients to investigate the skeleton and subsequently the lung and other organs. This was the birth or radiology. Rapidly they observed skin erythema, which led to the idea of using X-rays against a variety of lesions. In June 1896 the first patient was treated by radiotherapy. J.J. Thomson (Cambridge, U.K.) showed that X-rays were able to ionize gaz and the study of this phenomenon led to the discovery of electrons in 1897. In order to understand the emission of X-rays, H. Becquerel (Paris) investigated the role of the phosphorescence of the glass of the tube and while doing so discovered radioactivity in March 1896. X-rays and radioactivity were at the origin of the scientific revolution at the end of the 19th and the beginning of the 20th centuries. Research on radioactive materials demonstrated the existence of atoms which had been till then only a convenient hypothesis for explaining chemical reactions, but whose reality was considered as dubious by most physicists. Moreover, interaction of particles emitted by radionuclides and atoms enabled first the study of the structure of the atom and subsequently its nucleus. Matter, elements which were thought to be immutable were found to be transmutable, and eventually to disintegrate. The origin of the energy transferred to the radiation which was emitted appeared as a mystery and in order to explain it the physicist had to accept that matter could convert energy. In 1903 Einstein established the equivalence between matter and energy. Matter, energy, electricity, light which were formerly considered as continuous quantities were found to be discrete: there are particles of matter (elementary particles), energy (quanta, Planck 1905), electricity (electron), light (photons). Radioactive decay, particle interactions imposed a probabilistic physics which progressively replaced classic deterministic physics. Radioactivity can be used as a clock to measure time in the universe. Datations were made for fossils, art masterpieces and also for the earth, the solar system and universe. X-rays diffraction proved to be a powerful tool for studying crystals and molecules, in particular protein, and in 1953 enabled to demonstrate the DNA double helix. Hence X-rays and radioactivity originated a revolution in physics and science and in the vision of nature. The imperceptible and yet so powerful rays demonstrated the deficiencies of our senses. Mathematical entities and instrumentation must complement our sensations. The huge increment in our knowledge is accompanied by a divorce between the scientist and the layman who now often has great difficulties understanding new concepts not only in physics but also in biology.

  10. [Wilhelm Conrad Röntgen and the discovery of X-rays].

    PubMed

    Tubiana, M

    1996-01-01

    W.C. Röntgen reported the discovery of X-rays in December 1895 after seven weeks of assiduous work during which he had studied the properties of this new type of radiation able to go through screens of notable thickness. He named them X-rays to underline the fact that their nature was unknown. The news of this discovery immediately aroused an immense interest in the public and also initiated intense research in several directions. Physicians and physicists began as early as January 1896 to use X-rays on patients to investigate the skeleton and subsequently the lung and other organs. This was the birth or radiology. Rapidly they observed skin erythema, which led to the idea of using X-rays against a variety of lesions. In June 1896 the first patient was treated by radiotherapy. J.J. Thomson (Cambridge, U.K.) showed that X-rays were able to ionize gaz and the study of this phenomenon led to the discovery of electrons in 1897. In order to understand the emission of X-rays, H. Becquerel (Paris) investigated the role of the phosphorescence of the glass of the tube and while doing so discovered radioactivity in March 1896. X-rays and radioactivity were at the origin of the scientific revolution at the end of the 19th and the beginning of the 20th centuries. Research on radioactive materials demonstrated the existence of atoms which had been till then only a convenient hypothesis for explaining chemical reactions, but whose reality was considered as dubious by most physicists. Moreover, interaction of particles emitted by radionuclides and atoms enabled first the study of the structure of the atom and subsequently its nucleus. Matter, elements which were thought to be immutable were found to be transmutable, and eventually to disintegrate. The origin of the energy transferred to the radiation which was emitted appeared as a mystery and in order to explain it the physicist had to accept that matter could convert energy. In 1903 Einstein established the equivalence between matter and energy. Matter, energy, electricity, light which were formerly considered as continuous quantities were found to be discrete: there are particles of matter (elementary particles), energy (quanta, Planck 1905), electricity (electron), light (photons). Radioactive decay, particle interactions imposed a probabilistic physics which progressively replaced classic deterministic physics. Radioactivity can be used as a clock to measure time in the universe. Datations were made for fossils, art masterpieces and also for the earth, the solar system and universe. X-rays diffraction proved to be a powerful tool for studying crystals and molecules, in particular protein, and in 1953 enabled to demonstrate the DNA double helix. Hence X-rays and radioactivity originated a revolution in physics and science and in the vision of nature. The imperceptible and yet so powerful rays demonstrated the deficiencies of our senses. Mathematical entities and instrumentation must complement our sensations. The huge increment in our knowledge is accompanied by a divorce between the scientist and the layman who now often has great difficulties understanding new concepts not only in physics but also in biology. PMID:8696882

  11. Rediscovery of Leptoxis compacta (Anthony, 1854) (Gastropoda: Cerithioidea: Pleuroceridae)

    PubMed Central

    Whelan, Nathan V.; Johnson, Paul D.; Harris, Phil M.

    2012-01-01

    The Mobile River Basin is a hotspot of molluscan endemism, but anthropogenic activities have caused at least 47 molluscan extinctions, 37 of which were gastropods, in the last century. Nine of these suspected extinctions were in the freshwater gastropod genus Leptoxis (Cerithioidea: Pleuroceridae). Leptoxis compacta, a Cahaba River endemic, has not been collected for >70 years and was formally declared extinct in 2000. Such gastropod extinctions underscore the imperilment of freshwater resources and the current biodiversity crisis in the Mobile River Basin. During a May 2011 gastropod survey of the Cahaba River in central Alabama, USA, L. compacta was rediscovered. The identification of snails collected was confirmed through conchological comparisons to the L. compacta lectotype, museum records, and radulae morphology of historically collected L. compacta. Through observations of L. compacta in captivity, we document for the first time that the species lays eggs in short, single lines. Leptoxis compacta is restricted to a single location in the Cahaba River, and is highly susceptible to a single catastrophic extinction event. As such, the species deserves immediate conservation attention. Artificial propagation and reintroduction of L. compacta into its native range may be a viable recovery strategy to prevent extinction from a single perturbation event. PMID:22905139

  12. Redescription of Bellerophon bittneri (Gastropoda: Triassic) from Wyoming.

    USGS Publications Warehouse

    Yochelson, E.L.; Boyd, D.W.; Wardlaw, B.

    1985-01-01

    Bellerophon bittneri Newell and Kummel is an Early Triassic bellerophontacean from the Dinwoody Formation in the Wind River Mountains. The available type material consists of one fair, but incomplete, external mold, which resembles a Bellerophon but is actually a Retispira. After repeated search, additional specimens were found at one locality in the southern Wind River Range of Wyoming; Retispira bittneri is redescribed from this new material. Like other Triassic bellerophontaceans, there is nothing unusual about the species apart from occurrence in the Mesozoic; it is clearly congeneric with Permian Retispira from underlying rocks. -Authors

  13. Morphological analysis of the Chinese Cipangopaludina species (Gastropoda; Caenogastropoda: Viviparidae)

    PubMed Central

    LU, Hong-Fa; DU, Li-Na; LI, Zhi-Qiang; CHEN, Xiao-Yong; YANG, Jun-Xing

    2014-01-01

    Viviparidae are widely distributed around the globe, but there are considerable gaps in the taxonomic record. To date, 18 species of the viviparid genus Cipangopaludina have been recorded in China, but there is substantial disagreement on the validity of this taxonomy. In this study, we described the shell and internal traits of these species to better discuss the validity of related species. We found that C. ampulliformis is synonym of C. lecythis, and C. wingatei is synonym of C. chinensis, while C. ampullacea and C. fluminalis are subspecies of C. lecythis and C. chinensis, respectively. C. dianchiensis should be paled in the genus Margarya, while C. menglaensis and C. yunnanensis belong to genus Mekongia. Totally, this leaves 11 species and 2 subspecies recorded in China. Based on whether these specimens’ spiral whorl depth was longer than aperture depth, these species or subspecies can be further divided into two groups, viz. chinensis group and cathayensis group, which can be determined from one another via the ratio of spiral depth and aperture depth, vas deferens and number of secondary branches of vas deferens. Additionally, Principal Component Analysis indicated that body whorl depth, shell width, aperture width and aperture length were main variables during species of Cipangopaludina. A key to all valid Chinese Cipangopaludina species were given. PMID:25465086

  14. Silurian Gastropoda from the Alexander terrane, southeast Alaska

    USGS Publications Warehouse

    Rohr, D.M.; Blodgett, R.B.

    2008-01-01

    Gastropods are described from Ludlow-age strata of the Heceta Limestone on Prince of Wales Island, southeast Alaska. They are part of a diverse megabenthic fauna of the Alexander terrane, an accreted terrane of Siberian or Uralian affinities. Heceta Limestone gastropods with Uralian affinities include Kirkospira glacialis, which closely resembles "Pleurotomaria" lindstromi Oehlert of Chernyshev, 1893, Retispira cf. R. volgulica (Chernyshev, 1893), and Medfracaulus turriformis (Chernyshev, 1893). Medfracaulus and similar morphotypes such as Coelocaulus karlae are unknown from rocks that are unquestionably part of the North American continent (Laurentia) during Late Silurian time. Beraunia is previously known only from the Silurian of Bohemia. Pachystrophia has previously been reported only from western North American terranes (Eastern Klamath, York, and Farewell terranes) and Europe. Bathmopterus Kirk, 1928, is resurrected and is only known from the Silurian of southeast Alaska. Newly described taxa include Hecetastoma gehrelsi n. gen. and n. sp. and Baichtalia tongassensis n. gen. and n. sp. ??2008 The Geological Society of America.

  15. Helicopsis persica n. sp. from northern Iran (Gastropoda: Geomitridae).

    PubMed

    Hausdorf, Bernhard; Bössneck, Ulrich

    2016-01-01

    Helicopsis Fitzinger, 1833 is a mainly eastern European genus of the xerophilous Helicellinae (Geomitridae, Helicoidea; for family systematics see Razkin et al. 2015) that is characterized by two symmetrical dart and accessory sacs. This is probably the plesiomorphous character state within the Geomitridae and Hygromiidae. Therefore, the delimitation and relationships of Helicopsis remained questionable (Hausdorf 1996). Most Helicopsis species are characterized by a lateral attachment of the outer layer of the penial papilla at the penis wall so that a cavity is separated in the proximal part of the penis (Schileyko 1978; Giusti et al. 1992; Hausdorf 1996). However, a similar cavity is present in some other Helicellinae (e.g., Pseudoxerophila, Xerolenta, Xeromunda). Giusti et al. (1992) considered these cavities artefacts, but it cannot be excluded that they are actually homologous to the cavity of Helicopsis. Therefore, it is doubtful whether such a cavity can be considered as an autapomorphy of Helicopsis. About ten species of Helicopsis are spread from Turkey and Bulgaria to the Ukraine with a centre of diversity on the Crimean peninsula. Only the type species, Helicopsis striata (Müller, 1774) is more widespread from Alsace in the west, the island Öland in the Baltic Sea in the north to Bulgaria and Turkey in the south and western Russia in the east. Furthermore, species from Morocco, Greece, Cyprus, Iran and the Kopetdag were classified as Helicopsis. The relationships between these species have to be examined in more detail. Here we describe a new Helicopsis species from Iran. PMID:27395547

  16. New Bythinella (Gastropoda, Bythinellidae) species from western Turkey

    PubMed Central

    Yıldırım, Mehmet Zeki; Kebapçı, Ümit; Koca, Seval Bahadır; Yüce, Arzu

    2015-01-01

    Abstract Bythinella anatolica sp. n., Bythinella istanbulensis sp. n., Bythinella magdalenae sp. n., and Bythinella wilkei sp. n. from western Turkey are described herein. Illustrations of the shell and genitalia of the newly described taxa, together with comparisons with previously known Bythinella taxa and a key to the species from western Turkey, are also provided. PMID:25685028

  17. Phylogenetic relationships among superfamilies of Neritimorpha (Mollusca: Gastropoda).

    PubMed

    Uribe, Juan E; Colgan, Don; Castro, Lyda R; Kano, Yasunori; Zardoya, Rafael

    2016-11-01

    Despite the extraordinary morphological and ecological diversity of Neritimorpha, few studies have focused on the phylogenetic relationships of this lineage of gastropods, which includes four extant superfamilies: Neritopsoidea, Hydrocenoidea, Helicinoidea, and Neritoidea. Here, the nucleotide sequences of the complete mitochondrial genomes of Georissa bangueyensis (Hydrocenoidea), Neritina usnea (Neritoidea), and Pleuropoma jana (Helicinoidea) and the nearly complete mt genomes of Titiscania sp. (Neritopsoidea) and Theodoxus fluviatilis (Neritoidea) were determined. Phylogenetic reconstructions using probabilistic methods were based on mitochondrial (13 protein coding genes and two ribosomal rRNA genes), nuclear (partial 28S rRNA, 18S rRNA, actin, and histone H3 genes) and combined sequence data sets. All phylogenetic analyses except one converged on a single, highly supported tree in which Neritopsoidea was recovered as the sister group of a clade including Helicinoidea as the sister group of Hydrocenoidea and Neritoidea. This topology agrees with the fossil record and supports at least three independent invasions of land by neritimorph snails. The mitochondrial genomes of Titiscania sp., G. bangueyensis, N. usnea, and T. fluviatilis share the same gene organization previously described for Nerita mt genomes whereas that of P. jana has undergone major rearrangements. We sequenced about half of the mitochondrial genome of another species of Helicinoidea, Viana regina, and confirmed that this species shares the highly derived gene order of P. jana.

  18. Physella acuta: atypical mitochondrial gene order among panpulmonates (Gastropoda).

    PubMed

    Nolan, Journey R; Bergthorsson, Ulfar; Adema, Coen M

    2014-11-01

    Mitochondrial (mt) sequences are frequently used for phylogenetic reconstruction and for identification of species of molluscs. This study expands the phylogenetic range of Hygrophila (Panpulmonata) for which such sequence data are available by characterizing the full mt genome of the invasive freshwater snail Physella acuta (Physidae). The mt genome sequences of two P. acuta isolates from Stubblefield Lake, New Mexico, USA, differed in length (14,490 vs 14,314 bp) and showed 11.49% sequence divergence, whereas ITS1 and ITS2 sequences from the nuclear genome differed by 1.75%. The mt gene order of P. acuta (cox1, P, nad6, nad5, nad1, D, F, cox2, Y, W, nad4L, C, Q, atp6, R, E, rrnS, M, T, cox3, I, nad2, K, V, rrnL, L1, A, cytb, G, H, L2, atp8, N, nad2, S1, S2, nad4) differs considerably from the relatively conserved gene order within Panpulmonata. Phylogenetic trees show that the 13 protein-encoding mt gene sequences (equivalent codons) of P. acuta group according to gastropod phylogeny, yet branch lengths and dN/dS ratios for P. acuta indicate elevated amino acid substitutions relative to other gastropods. This study indicates that mt sequences of P. acuta are phylogenetically informative despite a considerable intraspecific divergence and the atypical gene order in its mt genome.

  19. Physella acuta: atypical mitochondrial gene order among panpulmonates (Gastropoda)

    PubMed Central

    Nolan, Journey R.; Bergthorsson, Ulfar; Adema, Coen M.

    2014-01-01

    Mitochondrial (mt) sequences are frequently used for phylogenetic reconstruction and for identification of species of molluscs. This study expands the phylogenetic range of Hygrophila (Panpulmonata) for which such sequence data are available by characterizing the full mt genome of the invasive freshwater snail Physella acuta (Physidae). The mt genome sequences of two P. acuta isolates from Stubblefield Lake, New Mexico, USA, differed in length (14,490 vs 14,314 bp) and showed 11.49% sequence divergence, whereas ITS1 and ITS2 sequences from the nuclear genome differed by 1.75%. The mt gene order of P. acuta (cox1, P, nad6, nad5, nad1, D, F, cox2, Y, W, nad4L, C, Q, atp6, R, E, rrnS, M, T, cox3, I, nad2, K, V, rrnL, L1, A, cytb, G, H, L2, atp8, N, nad2, S1, S2, nad4) differs considerably from the relatively conserved gene order within Panpulmonata. Phylogenetic trees show that the 13 protein-encoding mt gene sequences (equivalent codons) of P. acuta group according to gastropod phylogeny, yet branch lengths and dN/dS ratios for P. acuta indicate elevated amino acid substitutions relative to other gastropods. This study indicates that mt sequences of P. acuta are phylogenetically informative despite a considerable intraspecific divergence and the atypical gene order in its mt genome. PMID:25368439

  20. A cladistic phylogeny of the family Patellidae (Mollusca: Gastropoda)

    PubMed Central

    Ridgway, S. A.

    1998-01-01

    A phylogenetic hypothesis for the patellid limpets is reconstructed by cladistic analysis of morphological characters from 37 species, representing all but one of the living members of the family. Characters included in the analysis are derived from shell shape and microstructure, headfoot and pallial complex, radula and sperm. The species fall into four clades, providing the basis for a new phylogenetic classification into four monophyletic genera: Helcion (four species; southern Africa), Cymbula (eight species; southern Africa, eastern Atlantic, southern Indian Ocean), Scutellastra (17 species; southern and southwestern Africa, Australia, Indo-West Pacific, Eastern Pacific) and Patella (nine species; northeastern Atlantic and Mediterranean). The analysis suggests sister-group relationships between Helcion and Cymbula, and between Scutellastra and Patella. In combination with present-day patterns of geographical distribution, this phylogenetic hypothesis is used to discuss the historical biogeography of the Patellidae. Scutellastra may have originated in southern Africa and dispersed across the Pacific, or alternatively may be a primitively Tethyan group. Both Helcion and Cymbula appear to have originated in southern Africa, but three Cymbula species have dispersed respectively to northwest Africa, St Helena and the southern Indian Ocean. The patellids of the northeastern Atlantic form a single clade, Patella (including P. pellucida), which may have arrived by northward dispersal of an ancestor from southern Africa, or possibly by vicariance of a widespread ancestral Tethyan distribution. The known fossil record of patellids is too fragmentary to permit choice between these alternatives.

  1. Redescription of Spirodentalium Walcott ( Gastropoda: Late Cambrian) from Wisconsin ( USA).

    USGS Publications Warehouse

    Yochelson, E.L.

    1987-01-01

    Spirodentalium Walcott, 1890, was originally described as a scaphopod. A reinterpretation of the type lot suggests that its overall shape is that of an open-coiled gastropod. If so, this is probably the earliest known open-coiled form and it is sinistral in coiling direction. -Author

  2. Silurian gastropoda from southeastern and west-central Alaska

    USGS Publications Warehouse

    Rohr, D.M.; Blodgett, R.B.; Fryda, J.

    2008-01-01

    Additional Silurian (Ludlovian) gastropods are described from the Heceta Formation in the Alexander terrane on Prince of Wales Island, southeastern Alaska. Species include Spinicharybdis krizi n. sp., Spinicharybdis boucoti n. sp., Morania wagneri n. sp., Haplospira craigi n. sp., Australonema sp., Pachystrophia cf. gotlandica (Lindstro??m, 1884), and Medfrazyga gilmulli n. sp. An additional new Silurian species, Morania nixonforkensis n. sp., is described from the Nixon Fork subterrane of the Farewell terrane of west-central Alaska. The spine-bearing Spinicharybdis is placed into a new subfamily Spinicharybdiinae together with Hystricoceras Jahn, 1894. Joint occurrences of genera Beraunia, Coelocaulus, and Morania, as well as members of subfamily Spinicharybdiinae in the gastropod fauna from the Heceta Formation, support its close relationship with gastropod fauna of Bohemia. Additionally, the occurrence of the genus Medfrazyga suggests a faunal link between the Alexander and Farewell terranes of Alaska. Medfrazyga gilmulli n. sp. is the oldest known and the only early Paleozoic member of the family Palaeozygopleuridae. Copyright ?? 2008, The Paleontological Society.

  3. Untersuchungen zum Harnsäuremetabolismus von Littorina littorea (Gastropoda)

    NASA Astrophysics Data System (ADS)

    Heil, K. P.; Eichelberg, D.

    1983-12-01

    Periwinkles, as typical inhabitants of sea-shores, are subjected to extreme changes of environmental conditions, which affect their excretion. In Littorina littorea uric acid, urea and ammonium were detected particularly in the kidney, but the only metabolite excreted was ammonium. Only the concentration of uric acid was dependent on the availability of water; decreasing periods of submersion during low tide and raised salinities caused a higher concentration of uric acid, while increasing periods of submersion and lowered salinities effected the opposite. Transfer of periwinkles within their intertidal habitat and laboratory experiments to test the effect of salinity showed that the concentration of uric acid in the kidney is adaptable. The dependence of uric acid concentration in the kidney on environmental conditions and the ammoniotelic excretion of L. littorea are discussed with regard to its particular living conditions. It is suggested that uric acid serves as nitrogen depot and has a particular function in osmoregulation.

  4. The Genus Cerion (Gastropoda: Cerionidae) in the Florida Keys

    PubMed Central

    2015-01-01

    The systematic relationships and phylogeography of Cerion incanum, the only species of Cerion native to the Florida Keys, are reviewed based on partial sequences of the mitochondrial COI and 16S genes derived from 18 populations spanning the range of this species and including the type localities of all four described subspecies. Our samples included specimens of Cerion casablancae, a species introduced to Indian Key in 1912, and a population of C. incanum x C. casablancae hybrids descended from a population of C. casablancae introduced onto Bahia Honda Key in the same year. Molecular data did not support the partition of C. incanum into subspecies, nor could populations be apportioned reliably into subspecies based on morphological features used to define the subspecies. Phylogenetic analyses affirmed the derived relationship of C. incanum relative to other cerionids, and indicated a Bahamian origin for the Cerion fauna of southern Florida. Relationships among the populations throughout the Keys indicate that the northernmost populations, closest to the Tomeu paleoislands that had been inhabited by Cerion petuchi during the Calabrian Pleistocene, are the oldest. The range of Cerion incanum expanded as the archipelago that is the Florida Keys was formed since the lower Tarantian Pleistocene by extension from the northeast to the southwest, with new islands populated as they were formed. The faunas of the High Coral Keys in the northeast and the Oölite Keys in the southwest, both with large islands that host multiple discontinuous populations of Cerion, are each composed of well supported clades that are characterized by distinctive haplotypes. In contrast, the fauna of the intervening Low Coral Keys consist of a heterogeneous series of populations, some with haplotypes derived from the High Coral Keys, others from the Oölite Keys. Individuals from the C. incanum x C. casablancae hybrid population inhabiting the southeastern coast of Bahia Honda Key were readily segregated based on their mitogenome lineage, grouping either with C. incanum or with C. casablancae from Indian Key. Hybrids with C. casablancae mitogenomes had haplotypes that were more divergent from their parent mitogenome than were hybrids with C. incanum mitogenomes. PMID:26378443

  5. Phylogenetic relationships among superfamilies of Neritimorpha (Mollusca: Gastropoda).

    PubMed

    Uribe, Juan E; Colgan, Don; Castro, Lyda R; Kano, Yasunori; Zardoya, Rafael

    2016-11-01

    Despite the extraordinary morphological and ecological diversity of Neritimorpha, few studies have focused on the phylogenetic relationships of this lineage of gastropods, which includes four extant superfamilies: Neritopsoidea, Hydrocenoidea, Helicinoidea, and Neritoidea. Here, the nucleotide sequences of the complete mitochondrial genomes of Georissa bangueyensis (Hydrocenoidea), Neritina usnea (Neritoidea), and Pleuropoma jana (Helicinoidea) and the nearly complete mt genomes of Titiscania sp. (Neritopsoidea) and Theodoxus fluviatilis (Neritoidea) were determined. Phylogenetic reconstructions using probabilistic methods were based on mitochondrial (13 protein coding genes and two ribosomal rRNA genes), nuclear (partial 28S rRNA, 18S rRNA, actin, and histone H3 genes) and combined sequence data sets. All phylogenetic analyses except one converged on a single, highly supported tree in which Neritopsoidea was recovered as the sister group of a clade including Helicinoidea as the sister group of Hydrocenoidea and Neritoidea. This topology agrees with the fossil record and supports at least three independent invasions of land by neritimorph snails. The mitochondrial genomes of Titiscania sp., G. bangueyensis, N. usnea, and T. fluviatilis share the same gene organization previously described for Nerita mt genomes whereas that of P. jana has undergone major rearrangements. We sequenced about half of the mitochondrial genome of another species of Helicinoidea, Viana regina, and confirmed that this species shares the highly derived gene order of P. jana. PMID:27456746

  6. A phylogeny of the land snails (Gastropoda: Pulmonata).

    PubMed Central

    Wade, C. M.; Mordan, P. B.; Clarke, B.

    2001-01-01

    We have undertaken the first large-scale molecular phylogenetic analysis of the Stylommatophora. Sequences of the ribosomal RNA gene-cluster were examined in 104 species of snails and slugs from 50 families, encompassing all the currently recognized major groups. It allows an independent test of the present classification based on morphology. At the level of families our molecular phylogeny closely supports the current taxonomy, but the deep branches within the tree do not. Surprisingly, a single assemblage including the families Achatinidae, Subulinidae and Streptaxidae lies near the base of the tree, forming a sister group to all remaining stylommatophorans. This primary division into 'achatinoid' and 'non-achatinoid' taxa is unexpected, and demands a radical reinterpretation of early stylommatophoran evolution. In particular, the Orthurethra appear to be relatively advanced within the 'non-achatinoid clade', and broadly equivalent to other super-familial clusters. This indicates that supposedly primitive features such as the orthurethran kidney are derived. The molecular tree also suggests that the origin of the Stylommatophora is much earlier than the main period of their diversification. PMID:11270439

  7. Locomotion of the filiform sperm of littorina (Gastropoda, Prosobranchia).

    PubMed

    Buckland-Nicks, J A; Chia, F S

    1981-01-01

    The filiform sperm of Littorina sitkana swims effectively in sea water and more viscous fluids, overcoming the problems of a non-uniform flagellar beat with an unusual mechanism, which involves three main events: (1) the sperm rotates anti-clockwise (looking from tail to head); then (2) stops rotating and stiffens itself to form a screw-shape, with the tail being held perpendicular to the middle piece, and finally; (3) reverses its rotation and propels itself forward in a clockwise spiral. The average velocity of sperm is approximately 184 micrometer/s with a rotational frequency of 24 revs/s. The mechanism of propulsion may involve two kinetic centers at opposite ends of the sperm, which coordinate their movements to produce anti-clockwise rotation, stationary twisting, or clockwise rotation, in a manner reminiscent of spirochaetes. Littorina sperm also exhibit slower methods of propulsion including swimming backwards (tail first) at 18 micrometer/s, and "gliding" at about 30 micrometer/s. The adaptive significance of the rapid propulsion is not obvious, because Littorina copulate and fertilize internally and at each stage in the transfer there are external aids to sperm transport, such as ciliary action (oviduct) and muscular expulsion (bursa and seminal receptacle). The filiform shape, however, is well-adapted for long-term storage in the female body. These points are discussed.

  8. Review of the Hispaniolan Parachondria (Chondropomorus) complex (Gastropoda: Littorinoidea: Annulariidae).

    PubMed

    Watters, G Thomas

    2016-01-01

    The Parachondria (Chondropomorus) complex in Hispaniola is reviewed. Nineteen species are recognized including eight new species: Parachondria anatolensis n. sp., Parachondria arcisensis n. sp., Parachondria daedalus n. sp., Parachondria heatheraikenae n. sp., Parachondria isabellinus n. sp., Parachondria muchai n. sp., Parachondria silvaticus n. sp., and Parachondria stigmosus n. sp. Distributional and habitat notes are given for additional taxa. Chondropoma marinum "Weinland" Reeve, 1863, is regarded as a nomen dubium. Chondropoma (Chondropomorus) moroni Bartsch, 1946, is reidentified as Crossepoma emilianum (Weinland, 1862). Chondropoma simplex Pfeiffer, 1852, regarded by Bartsch (1946) as a Chondropomorus, is considered a Chondropoma. PMID:27395623

  9. [Considerations concerning the award of the first Nobel Prize in Physics to Wilhelm Conrad Röntgen].

    PubMed

    Luberti, R F; Bagur, D B; Ponticelli, R; Brezina, A J

    1998-11-01

    By the end of the 19th century, the quantity of scientists of great value was so big that selecting one for the top prize was not easy at all. Opinions were divided, giving rise to the personal controversy depicted in this article.

  10. Temperature dependent larval occurrence and spat settlement of the invasive brackish water bivalve Mytilopsis leucophaeata (Conrad, 1831) (Dreissenidae)

    NASA Astrophysics Data System (ADS)

    van der Gaag, M.; van der Velde, G.; Wijnhoven, S.; Rajagopal, S.

    2014-03-01

    Mytilopsis leucophaeata, an invasive bivalve species, causes fouling problems by settling on submerged constructions and in cooling water circuits in brackish water. To predict spat fall we studied the larval occurrence and settlement of this species in the brackish Noordzeekanaal canal in the Netherlands for several years (1989-1992), while measuring water temperature, salinity and chlorophyll a levels. Larvae were collected monthly by means of a plankton net drawn across the whole width of the canal. Settled spat were collected from PVC panels exposed for one month. Larvae first appeared in May or June, and reached maximum numbers in June or July, before disappearing in October, November or even December. The larval period started at a water temperature of 14 °C, reached maximum numbers at 19-23 °C and ended when it fell below 9 °C. No larvae were observed anymore until the temperature rose to 14 °C in the spring of the next year. Spat fall (June-November) was related to the water temperature in April. If the water temperature in April was lower than 12.5 °C, spat fall started in July, while if temperature was already higher in April, it started a month earlier. The spat fall period started at 15 °C, with maximum numbers at 20-24 °C, and ended when the water temperature dropped below 5 °C. Redundancy analysis (RDA) demonstrated a strong relationship between larval and spat densities and water temperature.

  11. Evaluation of the use of Olivella minuta (Gastropoda, Olividae) and Hastula cinerea (Gastropoda, Terebridae) as TBT sentinels for sandy coastal habitats.

    PubMed

    Petracco, Marcelo; Camargo, Rita Monteiro; Berenguel, Thayana Amorim; de Arruda, Noelle C L Patrício; del Matto, Lygia A; Amado, Lílian Lund; Corbisier, Thais Navajas; Castro, Ítalo Braga; Turra, Alexander

    2015-07-01

    Tributyltin (TBT) contamination is still recorded in the environment even after its ban in antifouling paints. Since most biomonitors of TBT contamination, through imposex evaluation, are hard-bottom gastropods, the identification of soft-bottom sentinels has become useful for regions where rocky shores and coral reefs are absent. Thus, an evaluation of Olivella minuta and Hastula cinerea as monitors of TBT contamination was performed in two sandy beaches located under influence area of São Sebastião harbor (São Paulo state, Brazil), where previous and simultaneous studies have reported environmental contamination by TBT. In addition, the imposex occurrence in H. cinerea was assessed in an area with low marine traffic (Una beach), also located in São Paulo State. A moderate imposex incidence in O. minuta was detected in Pernambuco (% I = 9.36, RPLI = 4.49 and RPLIstand = 4.27) and Barequeçaba (% I = 2.42, RPLI = 0.36 and RPLIstand = 0.81) beaches, indicating TBT contamination. In contrast, more severe levels of imposex were recorded for H. cinerea in Una beach (% I = 12.45) and mainly in Barequeçaba beach (% I = 98.92, RPLI = 26.65). Our results suggest that O. minuta and H. cinerea have good potential as biomonitors for TBT based on their wide geographical distribution, common occurrence in different coastal sediment habitats, easy collection, and association with TBT-contaminated sediments. PMID:26085280

  12. Intracellular Immunohistochemical Detection of Tetrodotoxin in Pleurobranchaea maculata (Gastropoda) and Stylochoplana sp. (Turbellaria)

    PubMed Central

    Salvitti, Lauren R.; Wood, Susanna A.; Winsor, Leigh; Cary, Stephen Craig

    2015-01-01

    Tetrodotoxin (TTX), is a potent neurotoxin targeting sodium channels that has been identified in multiple marine and terrestrial organisms. It was recently detected in the Opisthobranch Pleurobranchaea maculata and a Platyhelminthes Stylochoplana sp. from New Zealand. Knowledge on the distribution of TTX within these organisms is important to assist in elucidating the origin and ecological role of this toxin. Intracellular micro-distribution of TTX was investigated using a monoclonal antibody-based immunoenzymatic technique. Tetrodotoxin was strongly localized in neutral mucin cells and the basement membrane of the mantle, the oocytes and follicles of the gonad tissue, and in the digestive tissue of P. maculata. The ova and pharynx were the only two structures to contain TTX in Stylochoplana sp. Using liquid chromatography-mass spectrometry, TTX was identified in the larvae and eggs, but not the gelatinous egg cases of P. maculata. Tetrodotoxin was present in egg masses of Stylochoplana sp. These data suggest that TTX has a defensive function in adult P. maculata, who then invest this in their progeny for protection. Localization in the digestive tissue of P. maculata potentially indicates a dietary source of TTX. Stylochoplana sp. may use TTX in prey capture and for the protection of offspring. PMID:25636158

  13. Dating and biogeographical patterns in the sea slug genus Acanthodoris Gray, 1850 (Mollusca, Gastropoda, Nudibranchia).

    PubMed

    Hallas, Joshua M; Simison, W Brian; Gosliner, Terrence M

    2016-04-01

    Recent studies investigating vicariance and dispersal have been focused on correlating major geological events with instances of taxonomic expansion by incorporating the fossil record with molecular clock analyses. However, this approach becomes problematic for soft-bodied organisms that are poorly represented in the fossil record. Here, we estimate the phylogenetic relationships of the nudibranch genus Acanthodoris Gray, 1850 using three molecular markers (16S, COI, H3), and then test two alternative geologically calibrated molecular clock scenarios in BEAST and their effect on ancestral area reconstruction (AAR) estimates employed in LAGRANGE. The global temperate distribution of Acanthodoris spans multiple geological barriers, including the Bering Strait (∼5.32 Mya) and the Baja Peninsula (∼5.5 Mya), both of which are used in our dating estimates. The expansion of the Atlantic Ocean (∼95-105 Mya) is also used to calibrate the relationship between A. falklandica Eliot, 1905 and A. planca Fahey and Valdés, 2005, which are distributed in southern Chile and South Africa respectively. Phylogenetic analyses recovered strong biogeographical signal and recovered two major clades representing northern and southern hemispheric distributions of Acanthodoris. When all three geological events are applied to the calibration analyses, the age for Acanthodoris is estimated to be mid-Cretaceous. When the expansion of the Atlantic Ocean is excluded from our analyses, however, Acanthodoris is estimated to be much younger, with a divergence time estimate during the Miocene. Regardless of divergence estimates, our AAR suggests that Acanthodoris may have origins in the Atlantic Ocean with the Atlantic acting as a dispersal point to the northeastern Pacific. These results suggest that Acanthodoris exhibits a rare instance of western trans-arctic expansion. This study also shows that northeast Pacific specimens of A. pilosa should be regarded as A. atrogriseata and that A. serpentinotus should be regarded as a synonym of A. pina.

  14. Bayerotrochus delicatus, a new species of pleurotomariid from Yap Seamount, near Palau, Western Pacific (Gastropoda: Pleurotomariidae).

    PubMed

    Zhang, Suping; Zhang, Shuqian; Wei, Peng

    2016-01-01

    A new pleurotomariid species, Bayerotrochus delicatus sp. nov., collected from the Yap Seamount, near Palau, Western Pacific (8°51'N, 137°47'E), is described and illustrated. The generic assignment is based on morphology and molecular evidence. The new species is characterized by a small, depressed trochoid shell sculptured with delicate spiral threads and axial riblets; the shell surface is lustrous orange mottled with iridescence. The radula has a formula of R + 3 + 23 + (ca. 30) + (ca. 65) + 9. These features can separate Bayerotrochus delicatus sp. nov. from its congeners. To determine the relationships of Bayerotrochus delicatus sp. nov. with other pleurotomariids, a neighbor-joining (NJ) tree was established using available sequences of cytochrome c oxidase I gene (COI) from this study and GenBank. PMID:27615927

  15. Progenesis in the evolution of the nudibranch mollusks genus Dendronotus (Gastropoda: Nudibranchia).

    PubMed

    Ekimova, I A; Malakhov, V V

    2016-03-01

    The morphology and postlarval ontogenesis of the radula in 11 species of the genus Dendronotus Alder et Hancock, 1845, has been studied. Four types of radula are recognized in adult mollusks. Proposed evidence suggests that small species of Dendronotus have evolved by progenesis. PMID:27193883

  16. Dating and biogeographical patterns in the sea slug genus Acanthodoris Gray, 1850 (Mollusca, Gastropoda, Nudibranchia).

    PubMed

    Hallas, Joshua M; Simison, W Brian; Gosliner, Terrence M

    2016-04-01

    Recent studies investigating vicariance and dispersal have been focused on correlating major geological events with instances of taxonomic expansion by incorporating the fossil record with molecular clock analyses. However, this approach becomes problematic for soft-bodied organisms that are poorly represented in the fossil record. Here, we estimate the phylogenetic relationships of the nudibranch genus Acanthodoris Gray, 1850 using three molecular markers (16S, COI, H3), and then test two alternative geologically calibrated molecular clock scenarios in BEAST and their effect on ancestral area reconstruction (AAR) estimates employed in LAGRANGE. The global temperate distribution of Acanthodoris spans multiple geological barriers, including the Bering Strait (∼5.32 Mya) and the Baja Peninsula (∼5.5 Mya), both of which are used in our dating estimates. The expansion of the Atlantic Ocean (∼95-105 Mya) is also used to calibrate the relationship between A. falklandica Eliot, 1905 and A. planca Fahey and Valdés, 2005, which are distributed in southern Chile and South Africa respectively. Phylogenetic analyses recovered strong biogeographical signal and recovered two major clades representing northern and southern hemispheric distributions of Acanthodoris. When all three geological events are applied to the calibration analyses, the age for Acanthodoris is estimated to be mid-Cretaceous. When the expansion of the Atlantic Ocean is excluded from our analyses, however, Acanthodoris is estimated to be much younger, with a divergence time estimate during the Miocene. Regardless of divergence estimates, our AAR suggests that Acanthodoris may have origins in the Atlantic Ocean with the Atlantic acting as a dispersal point to the northeastern Pacific. These results suggest that Acanthodoris exhibits a rare instance of western trans-arctic expansion. This study also shows that northeast Pacific specimens of A. pilosa should be regarded as A. atrogriseata and that A. serpentinotus should be regarded as a synonym of A. pina. PMID:26752594

  17. Transcriptome analysis in Concholepas concholepas (Gastropoda, Muricidae): mining and characterization of new genomic and molecular markers.

    PubMed

    Cárdenas, Leyla; Sánchez, Roland; Gomez, Daniela; Fuenzalida, Gonzalo; Gallardo-Escárate, Cristián; Tanguy, Arnaud

    2011-09-01

    The marine gastropod Concholepas concholepas, locally known as the "loco", is the main target species of the benthonic Chilean fisheries. Genetic and genomic tools are necessary to study the genome of this species in order to understand the molecular basis of its development, growth, and other key traits to improve the management strategies and to identify local adaptation to prevent loss of biodiversity. Here, we use pyrosequencing technologies to generate the first transcriptomic database from adult specimens of the loco. After trimming, a total of 140,756 Expressed Sequence Tag sequences were achieved. Clustering and assembly analysis identified 19,219 contigs and 105,435 singleton sequences. BlastN analysis showed a significant identity with Expressed Sequence Tags of different gastropod species available in public databases. Similarly, BlastX results showed that only 895 out of the total 124,654 had significant hits and may represent novel genes for marine gastropods. From this database, simple sequence repeat motifs were also identified and a total of 38 primer pairs were designed and tested to assess their potential as informative markers and to investigate their cross-species amplification in different related gastropod species. This dataset represents the first publicly available 454 data for a marine gastropod endemic to the southeastern Pacific coast, providing a valuable transcriptomic resource for future efforts of gene discovery and development of functional markers in other marine gastropods.

  18. Atlanta ariejansseni, a new species of shelled heteropod from the Southern Subtropical Convergence Zone (Gastropoda, Pterotracheoidea)

    PubMed Central

    Wall-Palmer, Deborah; Burridge, Alice K.; Peijnenburg, Katja T.C.A.

    2016-01-01

    Abstract The Atlantidae (shelled heteropods) is a family of microscopic aragonite shelled holoplanktonic gastropods with a wide biogeographical distribution in tropical, sub-tropical and temperate waters. The aragonite shell and surface ocean habitat of the atlantids makes them particularly susceptible to ocean acidification and ocean warming, and atlantids are likely to be useful indicators of these changes. However, we still lack fundamental information on their taxonomy and biogeography, which is essential for monitoring the effects of a changing ocean. Integrated morphological and molecular approaches to taxonomy have been employed to improve the assessment of species boundaries, which give a more accurate picture of species distributions. Here a new species of atlantid heteropod is described based on shell morphology, DNA barcoding of the Cytochrome Oxidase I gene, and biogeography. All specimens of Atlanta ariejansseni sp. n. were collected from the Southern Subtropical Convergence Zone of the Atlantic and Indo-Pacific oceans suggesting that this species has a very narrow latitudinal distribution (37–48°S). Atlanta ariejansseni sp. n. was found to be relatively abundant (up to 2.3 specimens per 1000 m3 water) within this narrow latitudinal range, implying that this species has adapted to the specific conditions of the Southern Subtropical Convergence Zone and has a high tolerance to the varying ocean parameters in this region. PMID:27551204

  19. Performance of 18S rRNA in littorinid phylogeny (Gastropoda: Caenogastropoda).

    PubMed

    Winnepenninckx, B M; Reid, D G; Backeljau, T

    1998-11-01

    In the past, 18S rRNA sequences have proved to be very useful for tracing ancient divergences but were rarely used for resolving more recent ones. Moreover, it was suggested that the molecule does not contain useful information to resolve divergences which took place during less than 40 Myr. The present paper takes littorinid phylogeny as a case study to reevaluate the utility of the molecule for resolving recent divergences. Two data sets for nine species of the snail family Littorinidae were analyzed, both separately and combined. One data set comprised 7 new complete 18S rRNA sequences aligned with 2 published littorinid sequences; the other comprised 12 morphological, 1 biochemical, and 2 18S rRNA secondary structure characters. On the basis of its ability to confirm generally accepted relationships and the congruence of results derived from the different data sets, it is concluded that 18S rRNA sequences do contain information to resolve "rapid" cladogenetic events, provided that they occurred in the not too distant past. 18S rRNA sequences yielded support for (1) the branching order (L. littorea, (L. obtusata, (L. saxatilis, L. compressa))) and (2) the basal position of L. striata in the Littorina clade. PMID:9797409

  20. [Inheritance of longitudinal shell bands in the snails Littorina obtusata and Littorina saxatilis (Gastropoda, Prosobranchia)].

    PubMed

    Kozminskiĭ, E V

    2011-08-01

    The hypothesis of a monogenic inheritance of dark longitudinal bands on the shell in the gastropods Littorina obtusata and L. saxatilis was checked. One gene having two alleles proved to be responsible for the shell banding pattern in both of the species. The presence of bands was a dominant character in either case. PMID:21954620

  1. Distinct genetic subdivision in sympatric and sibling species of the genus Littorina (Gastropoda: Littorinidae).

    PubMed

    Rolán-Alvarez, E; Zapata, C; Alvarez, G

    1995-01-01

    The genetic structure of two sibling and sympatric species of the genus Littorina was compared using allozymic loci. The two species are biologically and ecologically well-known and mostly show similar life history characteristics. Three populations of L. mariae Sacchi & Rastelli and L. obstusata (L.) were studied in the Muros-Noya Ria (Galicia, NW Spain). In addition, four microgeographical subsamples taken from one of the populations were analysed for each species. Age, sex and genotypes for nine polymorphic loci were studied in 1250 snails of both species. L. mariae showed larger genetic population subdivision and lower heterozygosity levels for the loci studied than did L. obtusata. Heterozygote deficiencies were found in only a few cases in natural populations of both species, usually affecting the Lap-1 locus. No significant genetic differences among age or sex classes were found. These results may be explained by the lower effective population size in L. mariae than in L. obtusata. Known differences between these species in generation interval and population density during the winter can cause the different effective population sizes suggested. These life history characteristics appear to provide the most likely explanations for the differences in genetic differentiation and heterozygosity between the two species. A previously unknown L. mariae morph from exposed shores is tentatively suggested to be conspecific. PMID:7852095

  2. [Inheritance of the background shell color in the snails Littorina obtusata (Gastropoda, Littorinidae)].

    PubMed

    Kozminsky, E V

    2014-10-01

    We investigated in a gastropod mollusk Littorina obtusata (L. obtusata) the inheritance of background shell coloration of the shell, which arises on the basis of three pigments: purple, orange, and yellow. We found that the hypothesis on polyallelic inheritance, as in the genus Cepaea, cannot explain the inheritance of shell color in periwinkles. We demonstrated that a separate genetic system is responsible for incorporation of each pigment into the shell. The composition of these genetic systems includes at least tw genes each in the case of the yellow and purple pigments. Our analysis shows that caution should be applied when extending the results obtained in the studies of the Cepaea genus to the other species of gastropods. PMID:25720250

  3. [Inheritance of white spots on the shell of Littorina obtusata (Gastropoda, Prosobranchia)].

    PubMed

    Kozminskiĭ, E V; Lezin, P A; Fokin, M V

    2010-12-01

    The hypothesis on monogenic inheritance of white spot pattern on the shell of the gastropod snail Littorina obtusata was tested. Although in most cases our results did not contradict this assumption, the hypothesis cannot explain the observed segregation in general. An alternative hypothesis was suggested, according to which the presence of spot pattern is controlled by two complementary biallelic genes. PMID:21434418

  4. Multiple paternity in Littorina obtusata (Gastropoda, Littorinidae) revealed by microsatellite analyses.

    PubMed

    Paterson, I G; Partridge, V; Buckland-Nicks, J

    2001-06-01

    Parental identity for juvenile Littorina obtusata was determined from three egg masses by means of microsatellite DNA markers. Results confirm that the attendant adult female in each case was the dam of the offspring and that at least 4-6 males contributed to each brood. This correlates with our behavioral observations that indicated multiple copulations between the female and several males in each experimental aquarium. A significant number of offspring from each brood were sired by non-sampled males (males that had copulated with females before capture) whose sperm had been stored by the female. This is the first direct evidence of multiple paternity in the Littorinidae. Results are discussed in reference to current theories of sperm competition, male precedence, and cryptic female choice. PMID:11441969

  5. Identification of Shell Colour Pigments in Marine Snails Clanculus pharaonius and C. margaritarius (Trochoidea; Gastropoda).

    PubMed

    Williams, S T; Ito, S; Wakamatsu, K; Goral, T; Edwards, N P; Wogelius, R A; Henkel, T; de Oliveira, L F C; Maia, L F; Strekopytov, S; Jeffries, T; Speiser, D I; Marsden, J T

    2016-01-01

    Colour and pattern are key traits with important roles in camouflage, warning and attraction. Ideally, in order to begin to understand the evolution and ecology of colour in nature, it is important to identify and, where possible, fully characterise pigments using biochemical methods. The phylum Mollusca includes some of the most beautiful exemplars of biological pigmentation, with the vivid colours of sea shells particularly prized by collectors and scientists alike. Biochemical studies of molluscan shell colour were fairly common in the last century, but few of these studies have been confirmed using modern methods and very few shell pigments have been fully characterised. Here, we use modern chemical and multi-modal spectroscopic techniques to identify two porphyrin pigments and eumelanin in the shell of marine snails Clanculus pharaonius and C margaritarius. The same porphyrins were also identified in coloured foot tissue of both species. We use high performance liquid chromatography (HPLC) to show definitively that these porphyrins are uroporphyrin I and uroporphyrin III. Evidence from confocal microscopy analyses shows that the distribution of porphyrin pigments corresponds to the striking pink-red of C. pharaonius shells, as well as pink-red dots and lines on the early whorls of C. margaritarius and yellow-brown colour of later whorls. Additional HPLC results suggest that eumelanin is likely responsible for black spots. We refer to the two differently coloured porphyrin pigments as trochopuniceus (pink-red) and trochoxouthos (yellow-brown) in order to distinguish between them. Trochopuniceus and trochoxouthos were not found in the shell of a third species of the same superfamily, Calliostoma zizyphinum, despite its superficially similar colouration, suggesting that this species has different shell pigments. These findings have important implications for the study of colour and pattern in molluscs specifically, but in other taxa more generally, since this study shows that homology of visible colour cannot be assumed without identification of pigments.

  6. Identification of Shell Colour Pigments in Marine Snails Clanculus pharaonius and C. margaritarius (Trochoidea; Gastropoda)

    PubMed Central

    Ito, S.; Wakamatsu, K.; Goral, T.; Edwards, N. P.; Wogelius, R. A.; Henkel, T.; de Oliveira, L. F. C.; Maia, L. F.; Strekopytov, S.; Speiser, D. I.; Marsden, J. T.

    2016-01-01

    Colour and pattern are key traits with important roles in camouflage, warning and attraction. Ideally, in order to begin to understand the evolution and ecology of colour in nature, it is important to identify and, where possible, fully characterise pigments using biochemical methods. The phylum Mollusca includes some of the most beautiful exemplars of biological pigmentation, with the vivid colours of sea shells particularly prized by collectors and scientists alike. Biochemical studies of molluscan shell colour were fairly common in the last century, but few of these studies have been confirmed using modern methods and very few shell pigments have been fully characterised. Here, we use modern chemical and multi-modal spectroscopic techniques to identify two porphyrin pigments and eumelanin in the shell of marine snails Clanculus pharaonius and C margaritarius. The same porphyrins were also identified in coloured foot tissue of both species. We use high performance liquid chromatography (HPLC) to show definitively that these porphyrins are uroporphyrin I and uroporphyrin III. Evidence from confocal microscopy analyses shows that the distribution of porphyrin pigments corresponds to the striking pink-red of C. pharaonius shells, as well as pink-red dots and lines on the early whorls of C. margaritarius and yellow-brown colour of later whorls. Additional HPLC results suggest that eumelanin is likely responsible for black spots. We refer to the two differently coloured porphyrin pigments as trochopuniceus (pink-red) and trochoxouthos (yellow-brown) in order to distinguish between them. Trochopuniceus and trochoxouthos were not found in the shell of a third species of the same superfamily, Calliostoma zizyphinum, despite its superficially similar colouration, suggesting that this species has different shell pigments. These findings have important implications for the study of colour and pattern in molluscs specifically, but in other taxa more generally, since this study shows that homology of visible colour cannot be assumed without identification of pigments. PMID:27367426

  7. Annotated type catalogue of the Bulimulidae (Mollusca, Gastropoda, Orthalicoidea) in the Natural History Museum, London

    PubMed Central

    Breure, Abraham S.H.; Ablett, Jonathan D.

    2014-01-01

    Abstract The type status is described of 404 taxa classified within the family Bulimulidae (superfamily Orthalicoidea) and kept in the London museum. Lectotypes are designated for Bulimus aurifluus Pfeiffer, 1857; Otostomus bartletti H. Adams, 1867; Helix cactorum d’Orbigny, 1835; Bulimus caliginosus Reeve, 1849; Bulimus chemnitzioides Forbes, 1850; Bulimus cinereus Reeve, 1849; Helix cora d’Orbigny, 1835; Bulimus fallax Pfeiffer, 1853; Bulimus felix Pfeiffer, 1862; Bulimus fontainii d’Orbigny, 1838; Bulimus fourmiersi d’Orbigny, 1837; Bulimus (Mesembrinus) gealei H. Adams, 1867; Bulimus gruneri Pfeiffer, 1846; Bulimus humboldtii Reeve, 1849; Helix hygrohylaea d’Orbigny, 1835; Bulimus jussieui Pfeiffer, 1846; Bulimulus (Drymaeus) binominis lascellianus E.A. Smith, 1895; Helix lichnorum d’Orbigny, 1835; Bulimulus (Drymaeus) lucidus da Costa, 1898; Bulimus luridus Pfeiffer, 1863; Bulimus meleagris Pfeiffer, 1853; Bulimus monachus Pfeiffer, 1857; Bulimus montagnei d’Orbigny, 1837; Helix montivaga d’Orbigny, 1835; Bulimus muliebris Reeve, 1849; Bulimus nigrofasciatus Pfeiffer in Philippi 1846; Bulimus nitelinus Reeve, 1849; Helix oreades d’Orbigny, 1835; Helix polymorpha d’Orbigny, 1835; Bulimus praetextus Reeve, 1849; Bulinus proteus Broderip, 1832; Bulimus rusticellus Morelet, 1860; Helix sporadica d’Orbigny, 1835; Bulimus sulphureus Pfeiffer, 1857; Helix thamnoica var. marmorata d’Orbigny, 1835; Bulinus translucens Broderip in Broderip and Sowerby I 1832; Helix trichoda d’Orbigny, 1835; Bulinus ustulatus Sowerby I, 1833; Bulimus voithianus Pfeiffer, 1847; Bulimus yungasensis d’Orbigny, 1837. The type status of the following taxa is changed to lectotype in accordance with Art. 74.6 ICZN: Bulimulus (Drymaeus) caucaensis da Costa, 1898; Drymaeus exoticus da Costa, 1901; Bulimulus (Drymaeus) hidalgoi da Costa, 1898; Bulimulus (Drymaeus) interruptus Preston, 1909; Bulimulus (Drymaeus) inusitatus Fulton, 1900; Bulimulus latecolumellaris Preston, 1909; Bulimus (Otostomus) napo Angas, 1878; Drymaeus notabilis da Costa, 1906; Drymaeus notatus da Costa, 1906; Bulimulus (Drymaeus) nubilus Preston, 1903; Drymaeus obliquistriatus da Costa, 1901; Bulimus (Drymaeus) ochrocheilus E.A. Smith, 1877; Bulimus (Drymaeus) orthostoma E.A. Smith, 1877; Drymaeus expansus perenensis da Costa, 1901; Bulimulus pergracilis Rolle, 1904; Bulimulus (Drymaeus) plicatoliratus da Costa, 1898; Drymaeus prestoni da Costa, 1906; Drymaeus punctatus da Costa, 1907; Bulimus (Leptomerus) sanctaeluciae E.A. Smith, 1889; Bulimulus (Drymaeus) selli Preston, 1909; Drymaeus subventricosus da Costa, 1901; Bulimulus (Drymaeus) tigrinus da Costa, 1898; Drymaeus volsus Fulton, 1907; Drymaeus wintlei Finch, 1929; Bulimus zhorquinensis Angas, 1879; Bulimulus (Drymaeus) ziczac da Costa, 1898. The following junior subjective synonyms are established: Bulimus antioquensis Pfeiffer, 1855 = Bulimus baranguillanus Pfeiffer, 1853; Drymaeus bellus da Costa, 1906 = Drymaeus blandi Pilsbry, 1897; Bulimus hachensis Reeve 1850 = Bulimus gruneri Pfeiffer, 1846 = Bulimus columbianus Lea, 1838; Bulimus (Otostomus) lamas Higgins 1868 = Bulimus trujillensis Philippi, 1867; Bulimulus (Drymaeus) binominis lascellianus E.A. Smith, 1895 = Bulimulus (Drymaeus) binominis E.A. Smith, 1895; Drymaeus multispira da Costa, 1904 = Helix torallyi d’Orbigny, 1835; Bulimulus (Drymaeus) plicatoliratus Da Costa, 1898 = Bulimus convexus Pfeiffer, 1855; Bulimus sugillatus Pfeiffer, 1857 = Bulimus rivasii d’Orbigny, 1837; Bulimus meridionalis Reeve 1848 [June] = Bulimus voithianus Pfeiffer, 1847. New combinations are: Bostryx montagnei (d’Orbigny, 1837); Bostryx obliquiportus (da Costa, 1901); Bulimulus heloicus (d’Orbigny, 1835); Drymaeus (Drymaeus) lusorius (Pfeiffer, 1855); Drymaeus (Drymaeus) trigonostomus (Jonas, 1844); Drymaeus (Drymaeus) wintlei Finch, 1929; Drymaeus (Mesembrinus) conicus da Costa, 1907; Kuschelenia (Kuschelenia) culminea culminea (d’Orbigny, 1835); Kuschelenia (Kuschelenia) culmineus edwardsi (Morelet, 1863); Kuschelenia (K.) gayi (Pfeiffer, 1857); Kuschelenia (Kuschelenia) tupacii (d’Orbigny, 1835); Kuschelenia (Vermiculatus) anthisanensis (Pfeiffer, 1853); Kuschelenia (Vermiculatus) aquilus (Reeve, 1848); Kuschelenia (Vermiculatus) bicolor (Sowerby I, 1835); Kuschelenia (Vermiculatus) caliginosus (Reeve, 1849); Kuschelenia (Vermiculatus) cotopaxiensis (Pfeiffer, 1853); Kuschelenia (Vermiculatus) filaris (Pfeiffer, 1853); Kuschelenia (Vermiculatus) ochracea (Morelet, 1863); Kuschelenia (Vermiculatus) petiti (Pfeiffer, 1846); Kuschelenia (Vermiculatus) purpuratus (Reeve, 1849); Kuschelenia (Vermiculatus) quechuarum (Crawford, 1939); Naesiotus cinereus (Reeve, 1849); Naesiotus dentritis (Morelet, 1863); Naesiotus fontainii (d’Orbigny, 1838); Naesiotus orbignyi (Pfeiffer, 1846); Protoglyptus pilosus (Guppy, 1871); Protoglyptus sanctaeluciae (E.A. Smith, 1889). Type material of the following taxa is figured herein for the first time: Bulimus cinereus Reeve, 1849; Bulimus coriaceus Pfeiffer, 1857; Bulimulus laxostylus Rolle, 1904; Bulimus pliculatus Pfeiffer, 1857; Bulimus simpliculus Pfeiffer, 1855. PMID:24715782

  8. Relationships Between Aphids (Insecta: Homoptera: Aphididae) and Slugs (Gastropoda: Stylommatophora: Agriolimacidae) Pests of Legumes (Fabaceae: Lupinus)

    PubMed Central

    Kozłowski, Jan; Strażyński, Przemysław; Jaskulska, Monika; Kozłowska, Maria

    2016-01-01

    Lupin plants are frequently damaged by various herbivorous invertebrates. Significant among these are slugs and aphids, which sometimes attack the same plants. Relationships between aphids, slugs and food plant are very interesting. Grazing by these pests on young plants can lead to significant yield losses. There is evidence that the alkaloids present in some lupin plants may reduce grazing by slugs, aphids and other invertebrates. In laboratory study was analyzed the relationships between aphid Aphis craccivora and slug Deroceras reticulatum pests of legumes Lupinus angustifolius. It was found that the presence of aphids significantly reduced slug grazing on the plants. The lupin cultivars with high alkaloid content were found to be less heavily damaged by D. reticulatum, and the development of A. craccivora was found to be inhibited on such plants. PMID:27324580

  9. [Reproductive cycle and index of condition used for Melongena corona (Mollusca: Gastropoda)].

    PubMed

    Zetina Zárate, A I; Aldana Aranda, D; Brule, T; Baqueiro Cárdenas, E

    2000-12-01

    Melongena corona bispinosa was studied in Yucatán, México (21 degrees 16' N, 89 degrees 49' W) for a year. Males have reproductive peaks in February and December, and a post-copulation peak in June. Female peaks are in March and May, plus oviposition peaks in April and January. Males and females differ in the mean gonadosom ic index (F=13.79, p<0.05) but not in the dry tissue/shell weight (F=0.0902, p<0.05), dry tissue and total weight (F=0.2466, p<0.05) and dry tissue weight/internal shell volume (F=1.0565, p<0.05). PMID:15266795

  10. Odontomariinae, a new middle paleozoic subfamily of slit-bearing euophaloidean gastropods (Euophalomorpha, Gastropoda)

    USGS Publications Warehouse

    Fryda, J.; Heidelberger, D.; Blodgett, R.B.

    2006-01-01

    A new subfamily, the Odontomariinae subfam. nov., is established herein for a distinctive group of uncoiled, slit-bearing Middle Devonian euomphalid gastropods. Its taxonomic position is based on the recent discovery of open coiled protoconchs and it is placed within the Euomphalomorpha. The genera Odontomaria Odontomaria C. F. Roemer and Tubiconcha n. gen. belonging to this new subfamily are enlarged based on studies on new material of the following species: Odontomaria semiplicata (Sandberger & Sandberger), Odontomaria gracilis n. sp., Odontomaria jankei n. sp., Odontomaria cheeneetnukensis n. sp., Odontomaria cindiprellerae n. sp. and Tubiconcha leunissi (Heidelberger, 2001). Members of the Odontomariinae were mainly sedentary organisms in high-energy, moderately shallow water. ?? 2006 E. Schweizerbart'sche Verlagsbuchhandlung.

  11. Granopupa in Iran, monophyly, and the fossil Granariinae (Gastropoda, Pulmonata, Chondrinidae)

    PubMed Central

    Gittenberger, Edmund; Kokshoorn, Bas; Bößneck, Ulrich; Reijnen, Bastian T.; Groenenberg, Dirk S. J.

    2016-01-01

    Abstract Indisputable Chondrinidae, Granariinae species, characterized by shell shape and apertural dentition, are known from Eocene deposits to the Recent. The generic classification of the extant species is based on conchological, anatomical and molecular data that are available now for most of the known species, including ‘Granaria’ persica as a representative of the once problematic group of so-called eastern Granaria species. According to molecular and anatomical characters, these eastern species have to be classified with Granopupa granum in Granopupa. Graniberia gen. n. is introduced for Granaria braunii on the basis of molecular and conchological data. For the pre-Pleistocene species, two generic names are equally well available now, viz. Granopupa and Granaria. Shell characters only do not enable a decision here. For the sake of nomenclatorial stability we propose to use Granaria for these species. Because both molecular and anatomical data most likely will never be known for the fossils, it will remain unclear whether the combined extant and extinct Granaria species form a monophyletic group. PMID:27408543

  12. Comparative morphology of Astraea latispina (Philippi, 1844) and Astraea olfersii (Philippi, 1846) (Mollusca, Gastropoda, Turbinidae).

    PubMed

    Monteiro, J C; Coelho, A C S

    2002-02-01

    The present study examines comparatively the soft parts of turbinids Astraea latispina and Astraea olfersii. The characters of soft parts of these species, in agreement with Trochoidea organization, allow a differential diagnosis on the cefalic lappets, appendix of eye-stalk, hypobranchial glands, jaws, radulae, and stomach spiral caecum, which information will be helpful in taxonomic studies.

  13. The genus Cerithideopsis Thiele, 1929 (Gastropoda: Potamididae) in the Indo-West Pacific region.

    PubMed

    Reid, David G; Claremont, Martine

    2014-01-01

    The genus Cerithideopsis is most common in mangrove and salt marsh habitats of the New World tropics, but there is also a small radiation in the Indo-West Pacific region. Previously, these Indo-Pacific snails have generally been classified as Cerithidea largillierti (Philippi, 1848). Molecular phylogenetic analysis (partial sequences of mitochondrial COI and 16S rRNA, and nuclear 28S rRNA) of 15 specimens from 8 localities between Japan and Australia reveal three clades, among which there are small morphological differences and which show allopatric distributions. Cerithideopsis largillierti sensu stricto is restricted to Japan and China, while the two other species are described as new: C. australiensis occurs in tropical Australasia and C. malayensis is found from Malaysia to Java and the Philippines. All occur on mud and in pools with leaf litter, in the shaded landward and middle zones of mangrove forests, and do not climb the trees. The species accounts include full synonymies, detailed descriptions of shells based on 82 museum samples, descriptions of living animals, distribution records and maps, and notes on habitat and conservation status. PMID:24871714

  14. Bacteriological and biochemical assessment of marinating cephalopods, crustaceans and gastropoda during 24 weeks of storage.

    PubMed

    Ozogul, Yesim; Ozogul, Fatih; Olgunoglu, Ilkan A; Kuley, Esmeray

    2008-09-01

    The quality and safety parameters of mixed marinated seafood salad containing common octopus (Octopus vulgaris), shrimp (Parapenaeus longirostris), European squid (Loligo vulgaris), sea snail (Rapana thomasiana) and common cuttlefish (Sepia officinalis) at 4 degrees C during storage of 24 weeks were investigated. In addition, the nutritional value in terms of proximate and fatty acid composition of seafood salad was also determined. Sensory scores of seafood salad in terms of appearance, odour, flavour and texture slightly decreased throughout the storage period. However, at the end of the storage period (5 months), the marinated seafood salad was still acceptable by the panellist. At the beginning of storage the total volatile basic nitrogen (TVB-N) value was 6.05 mg/100 g flesh, and the TVB-N values rose to 11.19 mg TVB-N/flesh by the end of the storage period. The pH value of the marinated seafood salad showed fluctuations, ranging from 3.57 to 3.65, and did not change significantly during the storage period. The concentrations of the biogenic amines in both the muscle of all species and in the solution of salad were also investigated. Among the biogenic amines, histamine was not detected in all samples throughout the storage period. The putrescine and cadaverine levels increased throughout the storage period, with a lower increase in the solution of seafood salad. Salmonella, coliform, Escherichia coli and Staphylococcus aureus were not detected while the total viable count remained low (3 log CFU/g) after 3 months of storage. PMID:19086240

  15. Terrestrial slugs (Gastropoda, Pulmonata) in the NATURA 2000 areas of Cyprus island

    PubMed Central

    Vardinoyannis, Katerina; Demetropoulos, Simon; Mylonas, Moissis; A.Triantis, Kostas; Makris, Christodoulos; Georgiou, Gabriel; Wiktor, Andrzej; Demetropoulos, Andreas

    2012-01-01

    Abstract Terrestrial slugs of the Island of Cyprus were recently studied in the framework of a study of the whole terrestrial malacofauna of the island. The present work was carried out in the Natura 2000 conservation areas of the island in 155 sampling sites over three years (2004–2007). Museum collections as well as literature references were included. In total six species are present in the Natura 2000 areas of the island, belonging to three families: Limacidae, Agriolimacidae and Milacidae. One of the species, Milax riedeli, is a new record for the island. The distribution of the species across the island and in the surrounding areas is discussed. PMID:22451785

  16. Distribution and habitat preferences of the genus Biomphalaria (Gastropoda: Planorbidae) in Cuba.

    PubMed

    Vázquez Perera, Antonio Alejandro; Sánchez Noda, Jorge; Hevia Jiménez, Yosvania

    2010-02-01

    A study was carried out to determine the distribution and habitat preferences of several species of the genus Biomphalaria. Samples were taken at 350 freshwater locations in Cuba. Three species of Biomphalaria (Biomphalaria havanensis, Biomphalaria helophila and Biomphalaria pallida) were recorded based on their distribution. Of the three species, B. havanensis has the weakest distribution because it was identified in only one locality. The other species, B. helophila and B. pallida, are abundant in rivers and dams and have large populations in Cuba. However, the only species that appears to occur in ecosystems shared with thiarids is B. pallida, possibly due to recent introduction of thiarids, but always in fewer numbers. Here we discuss the possibility of these species to act as intermediary hosts of Schistosoma mansoni in Cuba over the basis of occurrence in natural and anthropic habitats.

  17. A new species of hydrobiid snails (Mollusca, Gastropoda, Hydrobiidae) from central Greece

    PubMed Central

    Radea, Canella

    2011-01-01

    Abstract Anew minute valvatiform species belonging to the genus Daphniola Radoman, 1973, Daphniola eptalophos sp. n., from mountain Parnassos, Greece is described. The new species has a transparent valvatiform-planispiral shell, wide and open umbilicus, grey-black pigmented soft body and head and a black penis with a small colorless outgrowth on the left side near its base. A comparative table of shell dimensions and a key to the species known for this endemic genus for Greece are provided. PMID:22144853

  18. [Morphobiochemical adaptations of Mediterranean Littorina punctata (Gmelin, 1790) (Mollusca, Gastropoda) to survival under supralittoral conditions].

    PubMed

    Aliakrinskaia, I O

    2014-01-01

    Behavioral and morphobiochemical adaptations of Littorina punctata to dwelling under supralittoral condi- tions are analyzed. A quantitative estimation of the hemoglobin content in the radular tissues of the mollusk is given. PMID:25735161

  19. Relationships Between Aphids (Insecta: Homoptera: Aphididae) and Slugs (Gastropoda: Stylommatophora: Agriolimacidae) Pests of Legumes (Fabaceae: Lupinus).

    PubMed

    Kozłowski, Jan; Strażyński, Przemysław; Jaskulska, Monika; Kozłowska, Maria

    2016-01-01

    Lupin plants are frequently damaged by various herbivorous invertebrates. Significant among these are slugs and aphids, which sometimes attack the same plants. Relationships between aphids, slugs and food plant are very interesting. Grazing by these pests on young plants can lead to significant yield losses. There is evidence that the alkaloids present in some lupin plants may reduce grazing by slugs, aphids and other invertebrates. In laboratory study was analyzed the relationships between aphid Aphis craccivora and slug Deroceras reticulatum pests of legumes Lupinus angustifolius. It was found that the presence of aphids significantly reduced slug grazing on the plants. The lupin cultivars with high alkaloid content were found to be less heavily damaged by D. reticulatum, and the development of A. craccivora was found to be inhibited on such plants.

  20. A new species of Lienardia (Gastropoda: Conoidea) from the Philippines and the Spratly Islands

    PubMed Central

    Rosenberg, Gary; Stahlschmidt, Peter

    2013-01-01

    A new species of Lienardia (Conoidea: Clathurellidae) is described from the Philippines and Spratly Islands and compared to L. giliberti Souverbie, 1874, with which it has been confused. The species is routinely found in lumun-lumun nets in the southern Philippines, particularly in the Panglao area, in depths of 50 and 110 m. Correlations between radular morphology and shell coloration support maintaining Lienardia and Clathurella as distinct genera. PMID:23913992

  1. The Vermetidae of the Gulf of Kachchh, western coast of India (Mollusca, Gastropoda)

    PubMed Central

    Joshi, Devanshi MukundRay; Mankodi, Pradeep C.

    2016-01-01

    Abstract Coral reefs are often termed underwater wonderlands due to the presence of an incredible biodiversity including numerous invertebrates and vertebrates. Among the dense population of benthic and bottom-dwelling inhabitants of the reef, many significant species remain hidden or neglected by researchers. One such example is the vermetids, a unique group of marine gastropods. The present study attempts for the first time to assess the density and identify preferred reef substrates in the Gulf of Kachchh, state of Gujarat, on the western coast of India. A total of three species of the family Vermetidae were recorded during the study and their substrate preferences identified. PMID:26877684

  2. A new phylogeny of the Cephalaspidea (Gastropoda: Heterobranchia) based on expanded taxon sampling and gene markers.

    PubMed

    Oskars, Trond R; Bouchet, Philippe; Malaquias, Manuel António E

    2015-08-01

    The Cephalaspidea is a diverse marine clade of euthyneuran gastropods with many groups still known largely from shells or scant anatomical data. The definition of the group and the relationships between members has been hampered by the difficulty of establishing sound synapomorphies, but the advent of molecular phylogenetics is helping to change significantly this situation. Yet, because of limited taxon sampling and few genetic markers employed in previous studies, many questions about the sister relationships and monophyletic status of several families remained open. In this study 109 species of Cephalaspidea were included covering 100% of traditional family-level diversity (12 families) and 50% of all genera (33 genera). Bayesian and maximum likelihood phylogenetics analyses based on two mitochondrial (COI, 16S rRNA) and two nuclear gene markers (28S rRNA and Histone-3) were used to infer the relationships of Cephalaspidea. The monophyly of the Cephalaspidea was confirmed. The families Cylichnidae, Diaphanidae, Haminoeidae, Philinidae, and Retusidae were found non-monophyletic. This result suggests that the family level taxonomy of the Cephalaspidea warrants a profound revision and several new family and genus names are required to reflect the new phylogenetic hypothesis presented here. We propose a new classification of the Cephalaspidea including five new families (Alacuppidae, Colinatydidae, Colpodaspididae, Mnestiidae, Philinorbidae) and one new genus (Alacuppa). Two family names (Acteocinidae, Laonidae) and two genera (Laona, Philinorbis) are reinstated as valid. An additional lineage with family rank (Philinidae "Clade 4") was unravelled, but no genus and species names are available to reflect the phylogeny and formal description will take place elsewhere. PMID:25916189

  3. The genus Cerithideopsis Thiele, 1929 (Gastropoda: Potamididae) in the Indo-West Pacific region.

    PubMed

    Reid, David G; Claremont, Martine

    2014-01-01

    The genus Cerithideopsis is most common in mangrove and salt marsh habitats of the New World tropics, but there is also a small radiation in the Indo-West Pacific region. Previously, these Indo-Pacific snails have generally been classified as Cerithidea largillierti (Philippi, 1848). Molecular phylogenetic analysis (partial sequences of mitochondrial COI and 16S rRNA, and nuclear 28S rRNA) of 15 specimens from 8 localities between Japan and Australia reveal three clades, among which there are small morphological differences and which show allopatric distributions. Cerithideopsis largillierti sensu stricto is restricted to Japan and China, while the two other species are described as new: C. australiensis occurs in tropical Australasia and C. malayensis is found from Malaysia to Java and the Philippines. All occur on mud and in pools with leaf litter, in the shaded landward and middle zones of mangrove forests, and do not climb the trees. The species accounts include full synonymies, detailed descriptions of shells based on 82 museum samples, descriptions of living animals, distribution records and maps, and notes on habitat and conservation status.

  4. Characterization of 15 microsatellite loci in the pulmonate snail Pseudosuccinea columella (Mollusca, Gastropoda).

    PubMed

    Nicot, Antoine; Dubois, Marie-Pierre; Debain, Chantal; David, Patrice; Jarne, Philippe

    2008-11-01

    We characterized 15 new variable microsatellites in the freshwater snail Pseudosuccinea (Lymnaea) columella, as well as conditions for multiplexing and simultaneously genotyping sets of loci. Two to six alleles were detected per locus over the six populations studied. Gene diversity ranged from 0.000 to 0.498, but essentially no heterozygous individuals were observed. This resulted in extremely high F(IS) estimates, and therefore high selfing rates. The F(ST) estimates ranged from 0.18 to 1 among populations, but was generally high. These markers will constitute efficient tools for investigating the population structure of this invasive species. Cross-species amplification was on the whole unsuccessful.

  5. Predation mechanisms of Rapana venosa (Gastropoda: Muricidae) in different biotopes along the Black Sea coast.

    PubMed

    Kosyan, Alisa

    2016-01-30

    Mechanisms of feeding by the invasive gastropod Rapana venosa from different biotopes of 11 sites along the Black Sea coast are discussed. Two methods--edge-drilling and suffocation--are used, but the prevailing method in a particular biotope depends on the type of bivalve prey. Drill signs were present on almost all shells of Chamelea gallina, captured by rapa whelks in field conditions, while in a field experiment, only 11% of all empty Mytilus galloprovincialis had drilling signatures. The degree of radula abrasion was also dependent on the available bivalves: it was the highest in biotopes with C. gallina and juvenile mussels, and the lowest in biotopes with large mussels. Intermediate degrees of abrasion were observed in biotopes with mixed prey: C. gallina and Anadara kagoshimensis, C. gallina and mussels, or small and large mussels. Since we observed only initial signs of drilling, simultaneous application of boring and suffocation could take place.

  6. Gastrocopta (Mollusca, Gastropoda, Pupillidae) in the Pilbara region of Western Australia

    PubMed Central

    Whisson, Corey S.; Köhler, Frank

    2013-01-01

    Abstract Six species of Gastrocopta have been identified from the Pilbara region, Western Australia, by means of comparative analyses of shell and mtDNA variation. Three of these species, Gastrocopta hedleyi, Gastrocopta larapinta and Gastrocopta servilis, have been recorded in the Pilbara for the first time. Gastrocopta sp. CW1 is probably new to science and might be endemic to the region. By contrast, Gastrocopta hedleyi, Gastrocopta larapinta and Gastrocopta mussoni are shown to be widespread. PMID:23653507

  7. Granopupa in Iran, monophyly, and the fossil Granariinae (Gastropoda, Pulmonata, Chondrinidae).

    PubMed

    Gittenberger, Edmund; Kokshoorn, Bas; Bößneck, Ulrich; Reijnen, Bastian T; Groenenberg, Dirk S J

    2016-01-01

    Indisputable Chondrinidae, Granariinae species, characterized by shell shape and apertural dentition, are known from Eocene deposits to the Recent. The generic classification of the extant species is based on conchological, anatomical and molecular data that are available now for most of the known species, including 'Granaria' persica as a representative of the once problematic group of so-called eastern Granaria species. According to molecular and anatomical characters, these eastern species have to be classified with Granopupa granum in Granopupa. Graniberia gen. n. is introduced for Granaria braunii on the basis of molecular and conchological data. For the pre-Pleistocene species, two generic names are equally well available now, viz. Granopupa and Granaria. Shell characters only do not enable a decision here. For the sake of nomenclatorial stability we propose to use Granaria for these species. Because both molecular and anatomical data most likely will never be known for the fossils, it will remain unclear whether the combined extant and extinct Granaria species form a monophyletic group. PMID:27408543

  8. Neuromuscular development of Aeolidiella stephanieae Valdéz, 2005 (Mollusca, Gastropoda, Nudibranchia)

    PubMed Central

    2010-01-01

    Background Studies on the development of the nervous system and the musculature of invertebrates have become more sophisticated and numerous within the last decade and have proven to provide new insights into the evolutionary history of organisms. In order to provide new morphogenetic data on opisthobranch gastropods we investigated the neuromuscular development in the nudibranch Aeolidiella stephanieae Valdéz, 2005 using immunocytochemistry as well as F-actin labelling in conjunction with confocal laser scanning microscopy (cLSM). Results The ontogenetic development of Aeolidiella stephanieae can be subdivided into 8 stages, each recognisable by characteristic morphological and behavioural features as well as specific characters of the nervous system and the muscular system, respectively. The larval nervous system of A. stephanieae includes an apical organ, developing central ganglia, and peripheral neurons associated with the velum, foot and posterior, visceral part of the larva. The first serotonergic and FMRFamidergic neural structures appear in the apical organ that exhibits an array of three sensory, flask-shaped and two non-sensory, round neurons, which altogether disappear prior to metamorphosis. The postmetamorphic central nervous system (CNS) becomes concentrated, and the rhinophoral ganglia develop together with the anlage of the future rhinophores whereas oral tentacle ganglia are not found. The myogenesis in A. stephanieae begins with the larval retractor muscle followed by the accessory larval retractor muscle, the velar or prototroch muscles and the pedal retractors that all together degenerate during metamorphosis, and the adult muscle complex forms de novo. Conclusions Aeolidiella stephanieae comprises features of the larval and postmetamorphic nervous as well as muscular system that represent the ground plan of the Mollusca or even the Trochozoa (e. g. presence of the prototrochal or velar muscle ring). On the one hand, A. stephanieae shows some features shared by all nudibranchs like the postmetamorphic condensation of the CNS, the possession of rhinophoral ganglia and the lack of oral tentacle ganglia as well as the de novo formation of the adult muscle complex. On the other hand, the structure and arrangement of the serotonergic apical organ is similar to other caenogastropod and opisthobranch gastropods supporting their sister group relationship. PMID:20205753

  9. A new species of Cerithium (Gastropoda: Cerithiidae) from the South China Sea

    NASA Astrophysics Data System (ADS)

    Sun, Qimeng; Zhang, Suping

    2014-09-01

    Specimens of a new species of Cerithiidae, Cerithium mangrovum n. sp., were collected during two surveys along the coasts of Hainan and Guangdong Province, China. Usually associated with potamidid snails, this species often occurs in large populations between the mid-high tidal zones in a range of habitats, including mangroves, grass beds, silt, mud, and coral reefs. C. mangrovum n. sp. has a slender and tapering shell and the straight-sided whorl bears three aligned beaded spiral cords. The thick outer lip has a wide posterior sinus. It morphologically resembles C. coralium Kiener, 1841. The shell of C. coralium is usually larger and wider and the spiral cords are not as beaded as in C. mangrovum n. sp. Its radula has a rachidian tooth with a shallow, wide, median basal projection while the rachidian tooth of C. mangrovum n. sp. has a moderately long, median basal projection.

  10. EPR Investigation of Gamma-Irradiated Rapana Thomasiana (Gastropoda, Muricidae) Shell

    SciTech Connect

    Seletchi, Emilia Dana; Duliu, Octavian G.; Georgescu, Rodica

    2007-04-23

    The shell of Rapana Thomasiana snail, a carnivorous gastropod collected from the coasts of the Black Sea (Romania) was investigated by using Electron Paramagnetic Resonance (EPR) spectroscopy. The samples in powder form were irradiated with a 60Co gamma-ray source at ambient temperature in the dose range between 1.06 and 11.3 kGy. The measurements showed that the EPR signal intensity enhanced following saturation exponential with the absorbed dose. The estimated EPR parameters: g1 = 1.9976, g2 = 2.0006, g3 = 2.0015, g4 = 2.0030 and g5 = 2.0043 revealed a complex spectrum consisting of CO{sub 2}{sup -}, CO{sub 3}{sup 3-} and CO{sub 3}{sup -} species. A very weak signal at g6 = 2.0057 was associated to SO{sub 2}{sup -} electron center. All EPR signals of gamma-irradiated samples decreased with various rate with the of 100 deg. C isothermal annealing time.

  11. Aquatic snails (Gastropoda) of the Savannah River Plant, Aiken, South Carolina

    SciTech Connect

    Wood, D.H.

    1982-04-01

    A system of taxonomic aids to the snails of the Savannah River Plant (SRP) area is presented. The first part of the system is a dichotomous key. Descriptive terms not used in general ecology have been defined in a glossary. The second part of the system is a series of illustrated descriptions which will confirm identifications made using the key. Illustrations were prepared from specimens collected on the SRP or in the Savannah River on or near the SRP, with the exception of a few uncommon species which have been illustrated by using specimens from the Academy of Natural Sciences of Philadelphia (ANSP). The Academy collected those specimens in surveys of the Savannah River from 1952 through 1975. Ecological and distributional notes, where available, are included with the species descriptions.

  12. A nomenclator of extant and fossil taxa of the Melanopsidae (Gastropoda, Cerithioidea).

    PubMed

    Neubauer, Thomas A

    2016-01-01

    This nomenclator provides details on all published names in the family-, genus-, and species-group, as well as for a few infrasubspecific names introduced for, or attributed to, the family Melanopsidae. It includes nomenclaturally valid names, as well as junior homonyms, junior objective synonyms, nomina nuda, common incorrect subsequent spellings, and as far as possible discussion on the current status in taxonomy. The catalogue encompasses three family-group names, 79 genus-group names, and 1381 species-group names. All of them are given in their original combination and spelling (except mandatory corrections requested by the Code), along with their original source. For each family- and genus-group name, the original classification and the type genus and type species, respectively, are given. Data provided for species-group taxa are type locality, type horizon (for fossil taxa), and type specimens, as far as available. PMID:27551193

  13. Histopathological effects of phenol on the digestive gland of amphimelania holandri fer. (gastropoda, prosobranchia)

    SciTech Connect

    Lajtner, J.; Erben, R.; Klobucar, G.I.V.

    1996-12-31

    Phenolic wastes are common water pollutants generated from a variety of industrial processes used in oil refineries, gas operations, coke ovens, coal gasification and by natural processes such as the decomposition of plant matter. Relatively high concentrations of phenol are found in rivers near the outlets of channels into which industrial waste waters have been discharged. There are data about the toxic effects of phenol on fish, and on some invertebrates, including snails. However, little is known about histopathological changes induced by phenol`s toxic effects, and these changes might be a basic indicator in assessing the condition of a particular water ecosystem. The existing data are mostly relevant for fish, and we know very little about the snail`s histopathology; however, the snail is a good research model due to its effectiveness as a pollution indicator species. This study attempts to establish the structure of the normal digestive gland and histopathological changes as a result of exposure to phenol. 22 refs., 4 figs.

  14. Activity of the mangrove snail Cerithidea decollata (Gastropoda: Potamididae) in a warm temperate South African estuary

    NASA Astrophysics Data System (ADS)

    Hodgson, Alan N.; Dickens, John

    2012-08-01

    A population of Cerithidea decollata, an intertidal marine gastropod usually found within mangroves, was studied within an area of Juncus kraussii in the upper reaches of the warm temperate Knysna estuary, which is at the southern-most limit of the recorded distribution of this snail. Activity (migratory and homing behaviour, distances travelled during foraging) of the snails was monitored over spring and neap tides in four seasons. Migratory patterns of the snails were affected by season, time of low tide (day vs night), tidal magnitude (spring vs neap) and zonation. In the summer and spring, a greater proportion of snails migrated from J. kraussii leaves onto the mud during the day at spring low tide. During neap tides in these two seasons, most snails did not climb J. kraussii leaves and remained on the mud, which was nearly always exposed. In autumn a few snails only were active and in winter snails were almost completely inactive, probably due to low air temperatures. Snails travelled greater distances on the mud on spring tides, during the diurnal low tides, and in the summer. No snails were found to home to individual J. kraussii leaves; however, homing behaviour was recorded to wooden poles within the Juncus wetland.

  15. A Tale That Morphology Fails to Tell: A Molecular Phylogeny of Aeolidiidae (Aeolidida, Nudibranchia, Gastropoda)

    PubMed Central

    Carmona, Leila; Pola, Marta; Gosliner, Terrence M.; Cervera, Juan Lucas

    2013-01-01

    Aeolidida is one of the largest clades of nudibranchs with at least 560 known species. However, its systematics has not been studied in a comprehensive manner. Phylogenetic analyses of larger clades such as Nudibranchia or Cladobranchia have usually included a poor sample of aeolids. Furthermore, phylogenetic studies at the family or generic level in Aeolidida are a few and far between. The first molecular phylogeny of the aeolid family Aeolidiidae is presented here. This study, the most comprehensive for Aeolidida to date, uses new sequences of two mitochondrial (COI and 16S) genes and one nuclear gene (H3). 251 specimens from members of seven families of Aeolidida, including 39 species of Aeolidiidae were studied. Excluding Pleurolidia juliae, Aeolidiidae is monophyletic. Our results resolve the systematic relationships within the Aeolidiidae at a generic level, requiring changes in the systematics of this family. Spurilla, Anteaeolidiella, Limenandra and Aeolidia are well-supported and monophyletic clades. Aeolidiella stephanieae is transferred to Berghia and Aeolidiopsis ransoni and Spurilla salaamica to Baeolidia, to maintain the monophyletic lineages reflected in this study. The systematics of Cerberilla remains unclear. Some species earlier attributed to Aeolidiella are now grouped in a previously unnamed clade that we designate as Bulbaeolidia gen. nov. PMID:23658794

  16. Redescription of Bellerophon asiaticus Wirth (Early Triassic: Gastropoda) from China, and a survey of Triassic Bellerophontacea.

    USGS Publications Warehouse

    Yochelson, E.Y.; Yin, Hongfu

    1985-01-01

    The bilaterally symmetrical gastropod Bellerophon asiaticus Wirth is redescribed from specimens collected in Guizhou Province, PRC. The species is reassigned to Retispira, a common late Paleozoic taxon. Retispira is another example of a Paleozoic gastropod genus that crossed the era boundary. Associated pelecypods that date these Guizhou occurrences as Early Triassic are well known species in PRC and are illustrated. Both Bellerophon and Euphemites probably occur in the Early Triassic, though the quality of illustrations leaves some uncertainty; the existence of Stachella in the Triassic is more problematic. There was no dramatic reduction of the Bellerophontacea from their abundance and diversity in the Permian. It may be a general phenomenon that most late Paleozoic family-level and many generic-level taxa of gastropods were unaffected by the late Permian 'crisis'. from Authors

  17. Zona localization of shell matrix proteins in mantle of Haliotis tuberculata (Mollusca, Gastropoda).

    PubMed

    Jolly, Cécile; Berland, Sophie; Milet, Christian; Borzeix, Sandrine; Lopez, Evelyne; Doumenc, Dominique

    2004-01-01

    Organic matrix from molluscan shells has the potential to regulate calcium carbonate deposition and crystallization. Control of crystal growth thus seems to depend on control of matrix protein secretion or activation processes in the mantle cells, about which little is known. Biomineralization is a highly orchestrated biological process. The aim of this work was to provide information about the source of shell matrix macromolecule production, within the external epithelium of the mantle. An in vivo approach was chosen to describe the histologic changes in the outer epithelium and in blood sinus distribution, associated with mantle cells implicated in shell matrix production. Our results characterized a topographic and time-dependent zonation of matrix proteins involved in shell biomineralization in the mantle of Haliotis.

  18. Patterns of diversity of the Rissoidae (Mollusca: Gastropoda) in the Atlantic and the Mediterranean region.

    PubMed

    Ávila, Sérgio P; Goud, Jeroen; de Frias Martins, António M

    2012-01-01

    The geographical distribution of the Rissoidae in the Atlantic Ocean and Mediterranean Sea was compiled and is up-to-date until July 2011. All species were classified according to their mode of larval development (planktotrophic and nonplanktotrophic), and bathymetrical zonation (shallow species--those living between the intertidal and 50 m depth, and deep species--those usually living below 50 m depth). 542 species of Rissoidae are presently reported to the Atlantic Ocean and the Mediterranean Sea, belonging to 33 genera. The Mediterranean Sea is the most diverse site, followed by Canary Islands, Caribbean, Portugal, and Cape Verde. The Mediterranean and Cape Verde Islands are the sites with higher numbers of endemic species, with predominance of Alvania spp. in the first site, and of Alvania and Schwartziella at Cape Verde. In spite of the large number of rissoids at Madeira archipelago, a large number of species are shared with Canaries, Selvagens, and the Azores, thus only about 8% are endemic to the Madeira archipelago. Most of the 542-rissoid species that live in the Atlantic and in the Mediterranean are shallow species (323), 110 are considered as deep species, and 23 species are reported in both shallow and deep waters. There is a predominance of nonplanktotrophs in islands, seamounts, and at high and medium latitudes. This pattern is particularly evident in the genera Crisilla, Manzonia, Onoba, Porosalvania, Schwartziella, and Setia. Planktotrophic species are more abundant in the eastern Atlantic and in the Mediterranean Sea. The results of the analysis of the probable directions of faunal flows support the patterns found by both the Parsimony Analysis of Endemicity and the geographical distribution. Four main source areas for rissoids emerge: Mediterranean, Caribbean, Canaries/Madeira archipelagos, and the Cape Verde archipelago. We must stress the high percentage of endemics that occurs in the isolated islands of Saint Helena, Tristan da Cunha, Cape Verde archipelago and also the Azores, thus reinforcing the legislative protective actions that the local governments have implemented in these islands during the recent years. PMID:22693430

  19. Dutrochus, a new microdomatid (Gastropoda) genus from the Middle Devonian (Eifelian) of west-central Alaska

    USGS Publications Warehouse

    Blodgett, R.B.

    1993-01-01

    A new gastropod genus, Dutrochus, is established for members of the family Microdomatidae that are characterized by a reticulate ornament of spiral cords and intersecting, finer collabral threads, with all but one spiral cord being of nearly equal strength, and the single remaining cord being of stronger (nearly twice the order) magnitude and being situated at the periphery. It is represented by the type and only known species, Dutrochus alaskensis n. gen. and sp., from the upper part (lower Eifelian) of the Lower? and Middle Devonian Cheeneetnuk Limestone. The genus is very close and nearly homeomorphic to the Permian microdomatid genus Glyptospira. -from Author

  20. Molecular phylogeny of the Ellobiidae (Gastropoda: Panpulmonata) supports independent terrestrial invasions.

    PubMed

    Romero, Pedro E; Pfenninger, Markus; Kano, Yasunori; Klussmann-Kolb, Annette

    2016-04-01

    Gastropods of the family Ellobiidae are an interesting group in which to study transitions from intertidal to terrestrial realms. However, the phylogenetic relationships within this family still lack resolution. We present a phylogenetic hypothesis of the Ellobiidae based on Bayesian and maximum likelihood phylograms. We used nuclear (18S, 28S, H3) and mitochondrial (16S, 12S, COI) data, increasing the numbers of markers and data, and making this the most comprehensive phylogenetic study of the family to date. Our results support phylogenetic hypotheses derived from morphological data, and provide a supported framework to evaluate the internal relationships within Ellobiidae. The resulting phylogenetic trees support the previous hypothesis that the Ellobiidae are monophyletic only if the Trimusculinae (Otina, Smeagol and Trimusculus) are considered part of this family. In addition, we found that the Carychiinae, Ellobiinae and Pythiinae are reciprocally monophyletic and closely related, with the Carychiinae as sister group to Ellobiinae. Relationships within Melampodinae and Pedipedinae and their phylogenetic positions remain unresolved. Land invasion by the Ellobiidae occurred independently in Carychiinae and Pythia during different geological times (Mesozoic and Cenozoic, respectively). Diversification in the family does not appear to be related to past climate and biotic changes, neither the Cretaceous-Paleogene boundary nor the lowering of the sea level in the Oligocene. PMID:26724408

  1. Systematics of the family Plectopylidae in Vietnam with additional information on Chinese taxa (Gastropoda, Pulmonata, Stylommatophora)

    PubMed Central

    Páll-Gergely, Barna; Hunyadi, András; Ablett, Jonathan; Lương, Hào Văn; Fred Naggs; Asami, Takahiro

    2015-01-01

    Abstract Vietnamese species from the family Plectopylidae are revised based on the type specimens of all known taxa, more than 600 historical non-type museum lots, and almost 200 newly-collected samples. Altogether more than 7000 specimens were investigated. The revision has revealed that species diversity of the Vietnamese Plectopylidae was previously overestimated. Overall, thirteen species names (anterides Gude, 1909, bavayi Gude, 1901, congesta Gude, 1898, fallax Gude, 1909, gouldingi Gude, 1909, hirsuta Möllendorff, 1901, jovia Mabille, 1887, moellendorffi Gude, 1901, persimilis Gude, 1901, pilsbryana Gude, 1901, soror Gude, 1908, tenuis Gude, 1901, verecunda Gude, 1909) were synonymised with other species. In addition to these, Gudeodiscus hemmeni sp. n. and Gudeodiscus messageri raheemi ssp. n. are described from north-western Vietnam. Sixteen species and two subspecies are recognized from Vietnam. The reproductive anatomy of eight taxa is described. Based on anatomical information, Halongella gen. n. is erected to include Plectopylis schlumbergeri and Plectopylis fruhstorferi. Additionally, the genus Gudeodiscus is subdivided into two subgenera (Gudeodiscus and Veludiscus subgen. n.) on the basis of the morphology of the reproductive anatomy and the radula. The Chinese Gudeodiscus phlyarius werneri Páll-Gergely, 2013 is moved to synonymy of Gudeodiscus phlyarius. A spermatophore was found in the organ situated next to the gametolytic sac in one specimen. This suggests that this organ in the Plectopylidae is a diverticulum. Statistically significant evidence is presented for the presence of calcareous hook-like granules inside the penis being associated with the absence of embryos in the uterus in four genera. This suggests that these probably play a role in mating periods before disappearing when embryos develop. Sicradiscus mansuyi is reported from China for the first time. PMID:25632253

  2. Update on the distribution and phylogenetics of Biomphalaria (Gastropoda: Planorbidae) populations in Guangdong Province, China.

    PubMed

    Attwood, Stephen W; Huo, Guan-Nan; Qiu, Jian-Wen

    2015-01-01

    In 1973 planorbid snails then identified as Biomphalaria straminea were discovered in Hong Kong, China. It was assumed that these snails had been introduced to Hong Kong via the import of tropical fish by air from South America. In 2012 Biomphalaria were found for the first time in Guangdong Province, China. In view of the renewed interest in these invasive snails, a morphological and DNA-sequence based phylogenetic study was undertaken for seven populations of Biomphalaria snails collected in Guangdong. Morphologically and phylogenetically, five of the populations clustered more closely with Biomphalaria kuhniana than with B. straminea. Levels of genetic diversity among the populations were about half those of autochthonous populations in Brazil, the phylogenetic relationships did not correlate with a radiation from any one international port in China, and different lineages appeared associated with different ports. Consequently in explaining the current distribution of the snails, multiple colonization events, each establishing a new local snail population near to maritime international container ports, were considered more likely than the spread of snails from Hong Kong to China. The displacement of B. straminea by B. kuhniana in Guangdong is considered as an explanation for the habitat changes observed among the snails between Hong Kong in the 1980s and the present. The conclusions of the study are that any risk of Schistosoma mansoni transmission in China is more likely to come from parasite importation in the intramolluscan stage, than from transmission by migrant workers from South America or Africa. In addition, although likely to be rare, sporadic outbreaks of imported schistosomiasis (caused by invading infected snails) could be a threat to public health in the vicinity of International container ports (not only in Guangdong Province). Further work is called for to investigate further the presence of B. kuhniana and its potential interactions with B. straminea (the former is thought to be incompatible with S. mansoni), and the responses of Chinese Biomphalaria to potential competitors such as Thiaridae. The current expansion of container ports in Brazil and Venezuela, and the increase in trade with China, is likely to accentuate any current risk of imported schistosomiasis, and surveillance around ports in China, together with further research, are necessary.

  3. Review of the genus Endothyrella Zilch, 1960 with description of five new species (Gastropoda, Pulmonata, Plectopylidae)

    PubMed Central

    Páll-Gergely, Barna; Budha, Prem B.; Naggs, Fred; Backeljau, Thierry; Asami, Takahiro

    2015-01-01

    Abstract All known taxa of the genus Endothyrella Zilch, 1960 (family Plectopylidae) are reviewed. Altogether 23 Endothyrella species are recognized. All species are illustrated and whenever possible, photographs of the available type specimens are provided. Five new species are described: Endothyrella angulata Budha & Páll-Gergely, sp. n., Endothyrella dolakhaensis Budha & Páll-Gergely, sp. n. and Endothyrella nepalica Budha & Páll-Gergely, sp. n. from Nepal, Endothyrella robustistriata Páll-Gergely, sp. n. from the Naga Hills, India, and Endothyrella inexpectata Páll-Gergely, sp. n. from Sichuan, China. Helix (Plectopylis) munipurensis Godwin-Austen, 1875 is synonymized with Helix (Plectopylis) serica Godwin-Austen, 1875, and Plectopylis (Endothyra) gregorsoni Gude, 1915 is synonymized with Helix (Plectopylis) macromphalus W. Blanford, 1870. Plectopylis plectostoma var. exerta Gude, 1901 is a synonym of Plectopylis plectostoma var. tricarinata Gude, 1896, which is a species in its own right. Five species of the genus Chersaecia viz. Plectopylis (Chersaecia) bedfordi Gude, 1915, Helix (Plectopylis) brahma Godwin-Austen, 1879, Helix (Plectopylis) Oglei Godwin-Austen, 1879, Helix (Plectopylis) serica Godwin-Austen, 1875, and Plectopylis (Endothyra) williamsoni Gude, 1915 are moved to Endothyrella. The holotype of Plectopylis hanleyi Godwin-Austen, 1879 seems to be lost; therefore, Plectopylis hanleyi is considered to be a nomen dubium. PMID:26692792

  4. Atlanta ariejansseni, a new species of shelled heteropod from the Southern Subtropical Convergence Zone (Gastropoda, Pterotracheoidea).

    PubMed

    Wall-Palmer, Deborah; Burridge, Alice K; Peijnenburg, Katja T C A

    2016-01-01

    The Atlantidae (shelled heteropods) is a family of microscopic aragonite shelled holoplanktonic gastropods with a wide biogeographical distribution in tropical, sub-tropical and temperate waters. The aragonite shell and surface ocean habitat of the atlantids makes them particularly susceptible to ocean acidification and ocean warming, and atlantids are likely to be useful indicators of these changes. However, we still lack fundamental information on their taxonomy and biogeography, which is essential for monitoring the effects of a changing ocean. Integrated morphological and molecular approaches to taxonomy have been employed to improve the assessment of species boundaries, which give a more accurate picture of species distributions. Here a new species of atlantid heteropod is described based on shell morphology, DNA barcoding of the Cytochrome Oxidase I gene, and biogeography. All specimens of Atlanta ariejansseni sp. n. were collected from the Southern Subtropical Convergence Zone of the Atlantic and Indo-Pacific oceans suggesting that this species has a very narrow latitudinal distribution (37-48°S). Atlanta ariejansseni sp. n. was found to be relatively abundant (up to 2.3 specimens per 1000 m(3) water) within this narrow latitudinal range, implying that this species has adapted to the specific conditions of the Southern Subtropical Convergence Zone and has a high tolerance to the varying ocean parameters in this region.

  5. Atlanta ariejansseni, a new species of shelled heteropod from the Southern Subtropical Convergence Zone (Gastropoda, Pterotracheoidea).

    PubMed

    Wall-Palmer, Deborah; Burridge, Alice K; Peijnenburg, Katja T C A

    2016-01-01

    The Atlantidae (shelled heteropods) is a family of microscopic aragonite shelled holoplanktonic gastropods with a wide biogeographical distribution in tropical, sub-tropical and temperate waters. The aragonite shell and surface ocean habitat of the atlantids makes them particularly susceptible to ocean acidification and ocean warming, and atlantids are likely to be useful indicators of these changes. However, we still lack fundamental information on their taxonomy and biogeography, which is essential for monitoring the effects of a changing ocean. Integrated morphological and molecular approaches to taxonomy have been employed to improve the assessment of species boundaries, which give a more accurate picture of species distributions. Here a new species of atlantid heteropod is described based on shell morphology, DNA barcoding of the Cytochrome Oxidase I gene, and biogeography. All specimens of Atlanta ariejansseni sp. n. were collected from the Southern Subtropical Convergence Zone of the Atlantic and Indo-Pacific oceans suggesting that this species has a very narrow latitudinal distribution (37-48°S). Atlanta ariejansseni sp. n. was found to be relatively abundant (up to 2.3 specimens per 1000 m(3) water) within this narrow latitudinal range, implying that this species has adapted to the specific conditions of the Southern Subtropical Convergence Zone and has a high tolerance to the varying ocean parameters in this region. PMID:27551204

  6. Rediae of echinostomatid and heterophyid trematodes suppress phagocytosis of haemocytes in Littorina littorea (Gastropoda: Prosobranchia).

    PubMed

    Iakovleva, Nadya V; Shaposhnikova, Tania G; Gorbushin, Alexander M

    2006-05-01

    A modulation of the phagocytic activity of hemocytes from the common periwinkle Littorina littorea by secretory-excretory products (SEP) released by trematode rediae during axenic in vitro cultivation was studied. The SEP released by the parasites Himasthla elongata (Echinostomatidae) and Cryptocotyle lingua (Heterophyidae) were found to inhibit the phagocytosis of zymozan particles by periwinkle hemocytes. The specificity of SEP effects was assessed: SEP of Himasthla militaris and Cryptocotyle concavum, two trematodes belonging to the same genera but infecting another closely related prosobranch snail Hydrobia ulvae, were also shown to be able to suppress L. littorea hemocytes phagocytic activity. However, no decrease in phagocytosis rate was observed when SEP of H. elongata and C. lingua were applied to monolayers of hemocytes from the bivalve mollusc Mytilus edulis. SEP from H. elongata was fractionated; only those fractions containing proteins of molecular weight more than 50 kDa were shown to possess inhibitory activity. Different H. elongata SEP concentrations were tested in for their ability to suppress phagocytosis by L. littorea hemocytes. Even very low SEP concentrations were shown to retain their ability to decrease phagocytosis rate, the inhibitory effect being dose-dependent. Hemocytes derived from snails naturally infected with H. elongata were also found to have lower phagocytic ability as compared to healthy individuals. PMID:16438967

  7. Reversal of density dependence of juvenile Littorina littorea (Gastropoda) growth in response to periphyton nutrient status

    NASA Astrophysics Data System (ADS)

    Sommer, Ulrich

    2001-05-01

    Experimental periphyton communities were grown in aquaria receiving media of differently enriched seawater (fully enriched, without Si enrichment, without N and P enrichment) and supplied differently with medium (batch and weekly replacement). Periphyton was subject to grazing by 1-6 individuals of juvenile Littorina littorea. Periphyton biomass was higher in the replacement aquaria than in the batch aquaria and higher in the full and the -Si medium than in the -NP medium. The N:C ratio of the periphyton increased with Littorina number in the batch aquaria and was unaffected by Littorina number in the replacement aquaria. Diatoms were most dominant in the -NP treatments and rarest in the -Si treatments. Chlorophytes were dominant in the -Si and the fully enriched treatments, but also Cyanobacteria contributed significantly to periphyton biomass in those treatments under nutrient replacement. Somatic growth of Littorina was negatively correlated to Littorina density in the replacement aquaria and positively density dependent in the batch aquaria. The latter is explained by improved food quality under stronger grazing pressure.

  8. Sphincterochilidae from Tunisia, with a note on the subgenus Rima Pallary, 1910 (Gastropoda, Pulmonata)

    PubMed Central

    Abbes, Intidhar; Nouira, Said; Neubert, Eike

    2011-01-01

    Abstract In order to establish an updated checklist of terrestrial gastropod from Tunisia, a revision of the species of Sphincterochilidae is presented, using bibliographic and museum records and the results of our own field work. As a result, only two species, Sphincterochila candidissima and Sphincterochila tunetana, are accepted to occur in Tunisia, and their type specimens are illustrated. The study of the morphological characters of the genital organs of both species clarified their subgeneric affiliation. Comparison of Sphincterochila tunetana with Sphincterochila cariosa from Lebanonshowed that the first has to be classified within the subgenus Albea, and the latter within Sphincterochila s. str.; the subgenus Rima Pallary, 1910 remains in the synonymy of Sphincterochila s. str. Bibliographic records of Sphincterochila baetica and Sphincterochila otthiana from Tunisia could not be confirmed, the latter probably lives close to the border with Algeria. PMID:22368450

  9. A nomenclator of extant and fossil taxa of the Valvatidae (Gastropoda, Ectobranchia)

    PubMed Central

    Haszprunar, Gerhard

    2014-01-01

    Abstract A compilation of all supra- and (infra-) specific taxa of extant and fossil Valvatidae, a group of freshwater operculate snails, is provided, including taxa initially described in this family and subsequently classified in other families, as well as names containing errors or misspellings. The extensive reference list is directly linked to the available electronic source (digital view or pdf-download) of the respective papers. PMID:24578604

  10. Taxonomic review of the genus Adelomelon (Gastropoda; Volutidae), based on type material.

    PubMed

    Wiggers, F; Veitenheimer-Mendes, I L

    2008-11-01

    The genus Adelomelon Dall, 1906 comprises a group of South American marine gastropods. We present updated information on the genus Adelomelon, with emphasis on the status and location of type material, including that of junior synonyms. Scaphella arnheimi Rivers, 1891 and Voluta paradoxa Lahille, 1895 are removed from the synonymy of Adelomelon ancilla (Lightfoot, 1758) and Adelomelon barattinii Klappenbach and Ureta, 1966 is included. The subgenus Weaveria Clench and Turner, 1964 is placed in synonymy with Adelomelon s.s. A key to the species of Adelomelon is provided.

  11. Caribbean Bulimulus revisited: physical moves and molecular traces (Mollusca, Gastropoda, Bulimulidae)

    PubMed Central

    2016-01-01

    Twenty-five samples of Bulimulus species are studied, partly from localities within their known distribution range, partly based on interceptions where the material originates from localities where the species seem to be recently introduced and non-native. Molecular study of cytochrome oxidase 1 (CO1) reveals the origin of some of these introductions, but is less conclusive for others. Four different methods for species delimitation were applied, which did not result in unambiguous species hypotheses. For a rapid identification of morphologically indistinct species, a more comprehensive database of sequences is needed. PMID:27069787

  12. Laboratory selection for increased tolerance to niclosamide in Bulinus truncatus (Gastropoda: Planorbidae) from Iran.

    PubMed

    Jelnes, J E

    1987-04-01

    Survivors of Bulinus truncatus from one exposure to niclosamide (Bayluscide) were used to establish the next generation in a five generation long laboratory selection for increased tolerance to niclosamide. In a comparison of the tolerance to the molluscicide between two original and two selected strains about 150 snails of each strain, divided into four size-groups, were exposed to aliquots of the same niclosamide solution on the same day and during the same time of the day. It was shown that five generations of relatively mild selection (30-50% survival) resulted in a significant increased tolerance to niclosamide in snails with only one exposure before start of the selection procedure. A comparison with published data indicated that the unselected strains did not change their tolerance to niclosamide during seven years of laboratory breeding. The strain exposed to niclosamide once in each of 16 generations showed an avoidance reaction to the chemical by crawling out of the water.

  13. Larval rearing, metamorphosis, growth and reproduction of the eolid nudibranch hermissenda crassicornis (eschscholtz, 1831) (gastropoda: opisthobranchia).

    PubMed

    Harrigan, J F; Alkon, D L

    1978-06-01

    1. Hermissenda crassicornis is a subannual nudibranch species that reproduces year-round. 2. There is a significant positive relationship between adult weight, diameter of the egg mass, estimated number of eggs per egg mass, and average number of eggs per capsule. 3. There is a planktonic veliger stage of 34 days minimum at 13 degrees -15 degrees C. 4. Larvae metamorphose on at least three species of hydroids. 5. To develop in reasonable numbers to a state competent to metamorphose veligers require a diet that includes phytoplankton of larger cell size (10-11 microm) than the commonly used Isochrysis and Monochrysis (5 microm). 6. Although Hermissenda feeds on a wide variety of sessile invertebrate species in the ocean, a diet of tunicate alone (Ciona intestinalis) promotes good growth and survival in the laboratory. 7. Egg mass deposition is initiated only after first copulation, except in the last month of life, and continues from about one-month post-metamorphosis to death, at about four months post-metamorphosis. Generation time (egg-to-egg) may be as short as 2.5 months. 8. A laboratory strain of Hermissenda is being established to provide animals of known history for research on the neural correlates of behavior. Animals, at least initially, are being selected for fast growth rate.

  14. Annotated type catalogue of the Amphibulimidae (Mollusca, Gastropoda, Orthalicoidea) in the Natural History Museum, London

    PubMed Central

    Breure, Abraham S.H.; Ablett, Jonathan D.

    2011-01-01

    Abstract The type status is described of 39 taxa classified within the family Amphibulimidae (superfamily Orthalicoidea) and kept in the London museum. One taxon, Bulimus elaeodes Pfeiffer, 1853, is removed to the Strophocheilidae. Lectotypes are designated for Bulimus adoptus Reeve, 1849; Bulimus (Eurytus) eros Angas, 1878; Helix onca d'Orbigny, 1835; Amphibulima pardalina Guppy, 1868. The type status of the following taxon is changed to lectotype in accordance with Art. 74.6 ICZN: Strophocheilus (Dryptus) jubeus Fulton, 1908. As general introduction to this and following papers on Orthalicoid types in the Natural History Museum, a brief history of the London collection is given and several examples of handwriting from different authors are presented. PMID:22144852

  15. Not so sluggish: the success of the Felimare picta complex (Gastropoda, Nudibranchia) crossing Atlantic biogeographic barriers

    PubMed Central

    Levy, André

    2016-01-01

    The molecular phylogeny of the Atlanto-Mediterranean species of the genus Felimare, particularly those attributed to the species F. picta, was inferred using two mitochondrial markers (16S and COI). A recent revision of the Chromodorididae clarified the taxonomic relationships at the family level redefining the genus Felimare. However, conflicting taxonomic classifications have been proposed for a restrict group of taxa with overlapping morphological characteristics and geographical distributions designated here as the Felimare picta complex. Three major groups were identified: one Mediterranean and amphi-Atlantic group; a western Atlantic group and a tropical eastern Atlantic group. F. picta forms a paraphyletic group since some subspecies are more closely related with taxa traditionaly classified as independent species (e.g. F. zebra) than with other subspecies with allopatric distributions (e.g. F. picta picta and F. picta tema). Usually, nudibranchs have adhesive demersal eggs, short planktonic larval phases and low mobility as adults unless rafting on floating materials occurs. Surprisingly however, the phylogeny of the F. picta complex suggests that they successfully cross main Atlantic biogeographic barriers including the mid-Atlantic barrier. This ability to cross different biogeographic barriers may be related to F. picta’s distinct life history and ecological traits. Compared to other Chromodorididae F. picta has larger eggs and planktotrophic larvae which could be related to a longer planktonic phase. PMID:26823995

  16. A new species of Bothriembryon (Mollusca, Gastropoda, Bothriembryontidae) from south-eastern Western Australia

    PubMed Central

    Whisson, Corey S.; Breure, Abraham S.H.

    2016-01-01

    Abstract Bothriembryon sophiarum sp. n. is described, based on shell and anatomical morphology, from the coastal area of south-easternmost Western Australia. This is the first description of a new extant Australian bothriembryontid in 33 years. The shell of Bothriembryon sophiarum is slender with a unique teleoconch sculpture. It is found in low coastal scrub on cliff edges and escarpments and because of its restricted distribution, qualifies as a short range endemic. PMID:27199583

  17. Mitochondrial DNA hyperdiversity and its potential causes in the marine periwinkle Melarhaphe neritoides (Mollusca: Gastropoda)

    PubMed Central

    Mardulyn, Patrick; Hardy, Olivier J.; Jordaens, Kurt; de Frias Martins, António Manuel; Backeljau, Thierry

    2016-01-01

    We report the presence of mitochondrial DNA (mtDNA) hyperdiversity in the marine periwinkle Melarhaphe neritoides (Linnaeus, 1758), the first such case among marine gastropods. Our dataset consisted of concatenated 16S-COI-Cytb gene fragments. We used Bayesian analyses to investigate three putative causes underlying genetic variation, and estimated the mtDNA mutation rate, possible signatures of selection and the effective population size of the species in the Azores archipelago. The mtDNA hyperdiversity in M. neritoides is characterized by extremely high haplotype diversity (Hd = 0.999 ± 0.001), high nucleotide diversity (π = 0.013 ± 0.001), and neutral nucleotide diversity above the threshold of 5% (πsyn = 0.0677). Haplotype richness is very high even at spatial scales as small as 100m2. Yet, mtDNA hyperdiversity does not affect the ability of DNA barcoding to identify M. neritoides. The mtDNA hyperdiversity in M. neritoides is best explained by the remarkably high mutation rate at the COI locus (μ = 5.82 × 10−5 per site per year or μ = 1.99 × 10−4 mutations per nucleotide site per generation), whereas the effective population size of this planktonic-dispersing species is surprisingly small (Ne = 5, 256; CI = 1,312–3,7495) probably due to the putative influence of selection. Comparison with COI nucleotide diversity values in other organisms suggests that mtDNA hyperdiversity may be more frequently linked to high μ values and that mtDNA hyperdiversity may be more common across other phyla than currently appreciated. PMID:27761337

  18. A nomenclator of extant and fossil taxa of the Melanopsidae (Gastropoda, Cerithioidea)

    PubMed Central

    Neubauer, Thomas A.

    2016-01-01

    Abstract This nomenclator provides details on all published names in the family-, genus-, and species-group, as well as for a few infrasubspecific names introduced for, or attributed to, the family Melanopsidae. It includes nomenclaturally valid names, as well as junior homonyms, junior objective synonyms, nomina nuda, common incorrect subsequent spellings, and as far as possible discussion on the current status in taxonomy. The catalogue encompasses three family-group names, 79 genus-group names, and 1381 species-group names. All of them are given in their original combination and spelling (except mandatory corrections requested by the Code), along with their original source. For each family- and genus-group name, the original classification and the type genus and type species, respectively, are given. Data provided for species-group taxa are type locality, type horizon (for fossil taxa), and type specimens, as far as available. PMID:27551193

  19. Identification of sequestered chloroplasts in photosynthetic and non-photosynthetic sacoglossan sea slugs (Mollusca, Gastropoda)

    PubMed Central

    2014-01-01

    Background Sacoglossan sea slugs are well known for their unique ability among metazoans to incorporate functional chloroplasts (kleptoplasty) in digestive glandular cells, enabling the slugs to use these as energy source when starved for weeks and months. However, members assigned to the shelled Oxynoacea and Limapontioidea (often with dorsal processes) are in general not able to keep the incorporated chloroplasts functional. Since obviously no algal genes are present within three (out of six known) species with chloroplast retention of several months, other factors enabling functional kleptoplasty have to be considered. Certainly, the origin of the chloroplasts is important, however, food source of most of the about 300 described species is not known so far. Therefore, a deduction of specific algal food source as a factor to perform functional kleptoplasty was still missing. Results We investigated the food sources of 26 sacoglossan species, freshly collected from the field, by applying the chloroplast marker genes tufA and rbcL and compared our results with literature data of species known for their retention capability. For the majority of the investigated species, especially for the genus Thuridilla, we were able to identify food sources for the first time. Furthermore, published data based on feeding observations were confirmed and enlarged by the molecular methods. We also found that certain chloroplasts are most likely essential for establishing functional kleptoplasty. Conclusions Applying DNA-Barcoding appeared to be very efficient and allowed a detailed insight into sacoglossan food sources. We favor rbcL for future analyses, but tufA might be used additionally in ambiguous cases. We narrowed down the algal species that seem to be essential for long-term-functional photosynthesis: Halimeda, Caulerpa, Penicillus, Avrainvillea, Acetabularia and Vaucheria. None of these were found in Thuridilla, the only plakobranchoidean genus without long-term retention forms. The chloroplast type, however, does not solely determine functional kleptoplasty; members of no-retention genera, such as Cylindrobulla or Volvatella, feed on the same algae as e.g., the long-term-retention forms Plakobranchus ocellatus or Elysia crispata, respectively. Evolutionary benefits of functional kleptoplasty are still questionable, since a polyphagous life style would render slugs more independent of specific food sources and their abundance. PMID:24555467

  20. A tale that morphology fails to tell: a molecular phylogeny of Aeolidiidae (Aeolidida, Nudibranchia, Gastropoda).

    PubMed

    Carmona, Leila; Pola, Marta; Gosliner, Terrence M; Cervera, Juan Lucas

    2013-01-01

    Aeolidida is one of the largest clades of nudibranchs with at least 560 known species. However, its systematics has not been studied in a comprehensive manner. Phylogenetic analyses of larger clades such as Nudibranchia or Cladobranchia have usually included a poor sample of aeolids. Furthermore, phylogenetic studies at the family or generic level in Aeolidida are a few and far between. The first molecular phylogeny of the aeolid family Aeolidiidae is presented here. This study, the most comprehensive for Aeolidida to date, uses new sequences of two mitochondrial (COI and 16S) genes and one nuclear gene (H3). 251 specimens from members of seven families of Aeolidida, including 39 species of Aeolidiidae were studied. Excluding Pleurolidia juliae, Aeolidiidae is monophyletic. Our results resolve the systematic relationships within the Aeolidiidae at a generic level, requiring changes in the systematics of this family. Spurilla, Anteaeolidiella, Limenandra and Aeolidia are well-supported and monophyletic clades. Aeolidiella stephanieae is transferred to Berghia and Aeolidiopsis ransoni and Spurilla salaamica to Baeolidia, to maintain the monophyletic lineages reflected in this study. The systematics of Cerberilla remains unclear. Some species earlier attributed to Aeolidiella are now grouped in a previously unnamed clade that we designate as Bulbaeolidia gen. nov.

  1. Taxonomic revision of the rock-dwelling door snail genus Montenegrina Boettger, 1877 (Mollusca, Gastropoda, Clausiliidae)

    PubMed Central

    Fehér, Zoltán; Szekeres, Miklós

    2016-01-01

    Abstract The genus Montenegrina is revised on the basis of material available at the Hungarian Natural History Museum (Budapest), Naturhistorisches Museum Wien (Vienna), and the Naturmuseum Senckenberg (Frankfurt am Main), as well as newly discovered populations. The following new taxa are described: Montenegrina haringae sp. n., Montenegrina lillae sp. n., Montenegrina prokletiana sp. n., Montenegrina sturanyana sp. n., Montenegrina grammica erosszoltani ssp. n., Montenegrina grammica improvisa ssp. n., Montenegrina hiltrudae desaretica ssp. n., Montenegrina hiltrudae selcensis ssp. n., Montenegrina laxa delii ssp. n., Montenegrina nana barinai ssp. n., Montenegrina prokletiana kovacsorum ssp. n., Montenegrina rugilabris golikutensis ssp. n., Montenegrina rugilabris gregoi ssp. n., Montenegrina skipetarica danyii ssp. n., Montenegrina skipetarica gurelurensis ssp. n., Montenegrina skipetarica pifkoi ssp. n., Montenegrina skipetarica puskasi ssp. n., Montenegrina sporadica tropojana ssp. n., Montenegrina sturanyana gropana ssp. n., Montenegrina sturanyana ostrovicensis ssp. n., and Montenegrina tomorosi hunyadii ssp. n. A neotype is designated for Montenegrina helvola (Küster, 1860), and Montenegrina cattaroensis antivaricostata nom. n. was introduced to replace the junior homonym Clausilia umbilicata costata Boettger, 1907 (non Pfeiffer, 1928). Of each taxon types or specimens from the type localities are figured, and distribution maps are provided. PMID:27408595

  2. The Model Organism Hermissenda crassicornis (Gastropoda: Heterobranchia) Is a Species Complex

    PubMed Central

    Lindsay, Tabitha

    2016-01-01

    Hermissenda crassicornis is a model organism used in various fields of research including neurology, ecology, pharmacology, and toxicology. In order to investigate the systematics of this species and the presence of cryptic species in H. crassicornis, we conducted a comprehensive molecular and morphological analysis of this species covering its entire range across the North Pacific Ocean. We determined that H. crassicornis constitutes a species complex of three distinct species. The name Hermissensa crassicornis is retained for the northeast Pacific species, occurring from Alaska to Northern California. The name H. opalescens is reinstated for a species occurring from the Sea of Cortez to Northern California. Finally, the name H. emurai is maintained for the northwestern species, found in Japan and in the Russian Far East. These three species have consistent morphological and color pattern differences that can be used for identification in the field. PMID:27105319

  3. Estimation of the density of Buccinum undatum (Gastropoda) off Douglas, Isle of Man

    NASA Astrophysics Data System (ADS)

    Kideys, A. E.

    1993-02-01

    The density of the common whelk ( Buccinum undatum L.) off Douglas, Isle of Man, was determined by four methods: (1) pot sampling, (2) diving, (3) mark-recapture experiment, and (4) underwater television. Although the values obtained by these methods were comparable, the last two methods yielded overestimations of Buccinum density. The results from diving survey and from pot sampling showed a good agreement, indicating that pot sampling can be used to determine the density of the common whelk, provided a good estimate of the pot attraction area is available. The range of whelk density between February 1989 and August 1990 resulting from pot sampling was between 0.08 and 0.38 individuals m-2. The temporal fluctuations of the whelk densities are discussed in detail.

  4. Determination of age and growth of Buccinum undatum L. (Gastropoda) off Douglas, Isle of Man

    NASA Astrophysics Data System (ADS)

    Kideys, A. E.

    1996-09-01

    Age and growth of Buccinum undatum off Douglas (Isle of Man, U.K.) were studied using four independent methods: length-frequency analyses (LFA), operculum analysis (OA), markrecapture experiment (MRE) and laboratory rearing (LR). Within the 16-month period between February 1989 and June 1990, only the January 1990 sample showed histograms allowing possible age group determination. Among the several length frequency analyses applied to this sample, the growth analysis program MIX calculated that Buccinum reaches mean lengths of 28.5, 45.8, 59.9, 71.5 and 81.0 mm at the end of its first, second, third, fourth and fifth year, respectively, with an asymptotic length (L∞) of 123.8 mm and Brody growth coefficient (K) of 0.20. Whilst the results from the LFA were supported by those from the OA and the MRE, growth in the laboratory differed; however, this was expected. Both K and L values found in this study are higher than those in two previous studies undertaken for Buccinum in northeastern England and northern France.

  5. Relationships Between Aphids (Insecta: Homoptera: Aphididae) and Slugs (Gastropoda: Stylommatophora: Agriolimacidae) Pests of Legumes (Fabaceae: Lupinus).

    PubMed

    Kozłowski, Jan; Strażyński, Przemysław; Jaskulska, Monika; Kozłowska, Maria

    2016-01-01

    Lupin plants are frequently damaged by various herbivorous invertebrates. Significant among these are slugs and aphids, which sometimes attack the same plants. Relationships between aphids, slugs and food plant are very interesting. Grazing by these pests on young plants can lead to significant yield losses. There is evidence that the alkaloids present in some lupin plants may reduce grazing by slugs, aphids and other invertebrates. In laboratory study was analyzed the relationships between aphid Aphis craccivora and slug Deroceras reticulatum pests of legumes Lupinus angustifolius. It was found that the presence of aphids significantly reduced slug grazing on the plants. The lupin cultivars with high alkaloid content were found to be less heavily damaged by D. reticulatum, and the development of A. craccivora was found to be inhibited on such plants. PMID:27324580

  6. Severnsia strombeulima n. gen. & sp. from Hawaii (Mollusca, Gastropoda: Caenogastropoda: Eulimidae).

    PubMed

    Geiger, Daniel L

    2016-01-01

    The malacofauna of Hawaii is rather well-known, owing to Kay (1979) and Severns (2011). Both works stand out because they include a large number of the generally under-represented micromollusks (<5 mm). Here a striking new genus and species of a microsnail is reported from that region. PMID:27394283

  7. Synopsis of Central Andean Orthalicoid land snails (Gastropoda, Stylommatophora), excluding Bulimulidae.

    PubMed

    Breure, Abraham S H; Avila, Valentín Mogollón

    2016-01-01

    A faunal overview is presented of the molluscan families Amphibulimidae, Megaspiridae, Odontostomidae, Orthalicidae, Simpulopsidae in Bolivia, Ecuador, and Peru. These Central Andean countries are known for their biodiverse malacofauna, of which the superfamily Orthalicoidea takes relatively a large share. In this paper the five families containing 103 (sub)species, for which systematic information (original publication, type locality, type depository, summarizing literature) and distributional records are presented. All species are illustrated by photographs of the type material or, if this could not be located, by a reproduction of the original figure. The following new taxon is introduced: Thaumastus (Thaumastus) sumaqwayqu sp. n. Junior subjective synonyms are established for: Plekocheilus (Sparnotion) Pilsbry, 1944 = Plekocheilus (Eudolichotis) Pilsbry, 1896; Scholvienia (Thomsenia) Strebel, 1910 = Scholvienia Strebel, 1910; Sultana (Trachyorthalicus) Strebel, 1909 = Sultana (Metorthalicus) Pilsbry, 1899; Plekocheilus (Eurytus) conspicuus Pilsbry, 1932 = Thaumastus (Thaumastus) hartwegi (Pfeiffer in Philippi, 1846); Zebra gruneri Strebel, 1909 = Orthalicus maracaibensis (Pfeiffer, 1856); Scholvienia jaspidea minor Strebel, 1910 = Scholvienia alutacea (Reeve, 1850); Bulimus bifasciatus unicolor Philippi, 1869 = Scholvienia brephoides (d'Orbigny, 1835). A new status is given to Plekocheilus mcgintyi 'Pilsbry' H.B. Baker, 1963 (subspecies of Bulinus piperitus Sowerby I, 1837); Strophocheilus superstriatus var. prodeflexus Pilsbry, 1895 (subspecies of Bulinus piperitus Sowerby I, 1837); Thaumastus (Quechua) salteri maximus Weyrauch, 1967 (subspecies of Thaumastus (Quechua) olmosensis Zilch, 1954); Pseudoglandina agitata Weyrauch, 1967 (nomen inquirendum). New combinations are: Clathrorthalicus corydon (Crosse, 1869), and Cyclodontina chuquisacana (Marshall, 1930). Lectotypes are now designated for Bulimus incisus Hupé, 1857 and Bulinus piperitus Sowerby I, 1837. PMID:27408531

  8. A new species of Bothriembryon (Mollusca, Gastropoda, Bothriembryontidae) from south-eastern Western Australia.

    PubMed

    Whisson, Corey S; Breure, Abraham S H

    2016-01-01

    Bothriembryon sophiarum sp. n. is described, based on shell and anatomical morphology, from the coastal area of south-easternmost Western Australia. This is the first description of a new extant Australian bothriembryontid in 33 years. The shell of Bothriembryon sophiarum is slender with a unique teleoconch sculpture. It is found in low coastal scrub on cliff edges and escarpments and because of its restricted distribution, qualifies as a short range endemic. PMID:27199583

  9. Prestonellinae-validation of the name as a new subfamily of Bothriembryontidae (Mollusca, Gastropoda, Orthalicoidea).

    PubMed

    Bruggen, A C Van; Herbert, David G; Breure, Abraham S H

    2016-01-01

    The affinities of the enigmatic South African land snail genus Prestonella Connolly, 1929 were discussed by Herbert (2007) and Herbert & Mitchell (2009), who showed, on the basis of morphological and molecular data, that the genus is referable to the superfamily Orthalicoidea. Currently, the three described species of Prestonella are the only known African representatives of this diverse superfamily. Earlier, van Bruggen (1978) had recognized that these species formed a distinct group and had placed them in the (new) family Prestonellidae. However, as noted by Bouchet & Rocroi (2005: 140), no diagnosis was provided by van Bruggen; the name Prestonellidae thus does not meet the requirements of ICZN Art. 13.1, and is not an available name. In this paper we will redress this issue, also taking into account more recent research which has shed light on the systematic position of this genus within the Orthalicoidea. PMID:27394284

  10. Identification of Shell Colour Pigments in Marine Snails Clanculus pharaonius and C. margaritarius (Trochoidea; Gastropoda).

    PubMed

    Williams, S T; Ito, S; Wakamatsu, K; Goral, T; Edwards, N P; Wogelius, R A; Henkel, T; de Oliveira, L F C; Maia, L F; Strekopytov, S; Jeffries, T; Speiser, D I; Marsden, J T

    2016-01-01

    Colour and pattern are key traits with important roles in camouflage, warning and attraction. Ideally, in order to begin to understand the evolution and ecology of colour in nature, it is important to identify and, where possible, fully characterise pigments using biochemical methods. The phylum Mollusca includes some of the most beautiful exemplars of biological pigmentation, with the vivid colours of sea shells particularly prized by collectors and scientists alike. Biochemical studies of molluscan shell colour were fairly common in the last century, but few of these studies have been confirmed using modern methods and very few shell pigments have been fully characterised. Here, we use modern chemical and multi-modal spectroscopic techniques to identify two porphyrin pigments and eumelanin in the shell of marine snails Clanculus pharaonius and C margaritarius. The same porphyrins were also identified in coloured foot tissue of both species. We use high performance liquid chromatography (HPLC) to show definitively that these porphyrins are uroporphyrin I and uroporphyrin III. Evidence from confocal microscopy analyses shows that the distribution of porphyrin pigments corresponds to the striking pink-red of C. pharaonius shells, as well as pink-red dots and lines on the early whorls of C. margaritarius and yellow-brown colour of later whorls. Additional HPLC results suggest that eumelanin is likely responsible for black spots. We refer to the two differently coloured porphyrin pigments as trochopuniceus (pink-red) and trochoxouthos (yellow-brown) in order to distinguish between them. Trochopuniceus and trochoxouthos were not found in the shell of a third species of the same superfamily, Calliostoma zizyphinum, despite its superficially similar colouration, suggesting that this species has different shell pigments. These findings have important implications for the study of colour and pattern in molluscs specifically, but in other taxa more generally, since this study shows that homology of visible colour cannot be assumed without identification of pigments. PMID:27367426

  11. Taxonomic revision of the rock-dwelling door snail genus Montenegrina Boettger, 1877 (Mollusca, Gastropoda, Clausiliidae).

    PubMed

    Fehér, Zoltán; Szekeres, Miklós

    2016-01-01

    The genus Montenegrina is revised on the basis of material available at the Hungarian Natural History Museum (Budapest), Naturhistorisches Museum Wien (Vienna), and the Naturmuseum Senckenberg (Frankfurt am Main), as well as newly discovered populations. The following new taxa are described: Montenegrina haringae sp. n., Montenegrina lillae sp. n., Montenegrina prokletiana sp. n., Montenegrina sturanyana sp. n., Montenegrina grammica erosszoltani ssp. n., Montenegrina grammica improvisa ssp. n., Montenegrina hiltrudae desaretica ssp. n., Montenegrina hiltrudae selcensis ssp. n., Montenegrina laxa delii ssp. n., Montenegrina nana barinai ssp. n., Montenegrina prokletiana kovacsorum ssp. n., Montenegrina rugilabris golikutensis ssp. n., Montenegrina rugilabris gregoi ssp. n., Montenegrina skipetarica danyii ssp. n., Montenegrina skipetarica gurelurensis ssp. n., Montenegrina skipetarica pifkoi ssp. n., Montenegrina skipetarica puskasi ssp. n., Montenegrina sporadica tropojana ssp. n., Montenegrina sturanyana gropana ssp. n., Montenegrina sturanyana ostrovicensis ssp. n., and Montenegrina tomorosi hunyadii ssp. n. A neotype is designated for Montenegrina helvola (Küster, 1860), and Montenegrina cattaroensis antivaricostata nom. n. was introduced to replace the junior homonym Clausilia umbilicata costata Boettger, 1907 (non Pfeiffer, 1928). Of each taxon types or specimens from the type localities are figured, and distribution maps are provided. PMID:27408595

  12. Caribbean Bulimulus revisited: physical moves and molecular traces (Mollusca, Gastropoda, Bulimulidae).

    PubMed

    Breure, Abraham S H

    2016-01-01

    Twenty-five samples of Bulimulus species are studied, partly from localities within their known distribution range, partly based on interceptions where the material originates from localities where the species seem to be recently introduced and non-native. Molecular study of cytochrome oxidase 1 (CO1) reveals the origin of some of these introductions, but is less conclusive for others. Four different methods for species delimitation were applied, which did not result in unambiguous species hypotheses. For a rapid identification of morphologically indistinct species, a more comprehensive database of sequences is needed.

  13. Synopsis of Central Andean Orthalicoid land snails (Gastropoda, Stylommatophora), excluding Bulimulidae

    PubMed Central

    Breure, Abraham S.H.; Avila, Valentín Mogollón

    2016-01-01

    Abstract A faunal overview is presented of the molluscan families Amphibulimidae, Megaspiridae, Odontostomidae, Orthalicidae, Simpulopsidae in Bolivia, Ecuador, and Peru. These Central Andean countries are known for their biodiverse malacofauna, of which the superfamily Orthalicoidea takes relatively a large share. In this paper the five families containing 103 (sub)species, for which systematic information (original publication, type locality, type depository, summarizing literature) and distributional records are presented. All species are illustrated by photographs of the type material or, if this could not be located, by a reproduction of the original figure. The following new taxon is introduced: Thaumastus (Thaumastus) sumaqwayqu sp. n. Junior subjective synonyms are established for: Plekocheilus (Sparnotion) Pilsbry, 1944 = Plekocheilus (Eudolichotis) Pilsbry, 1896; Scholvienia (Thomsenia) Strebel, 1910 = Scholvienia Strebel, 1910; Sultana (Trachyorthalicus) Strebel, 1909 = Sultana (Metorthalicus) Pilsbry, 1899; Plekocheilus (Eurytus) conspicuus Pilsbry, 1932 = Thaumastus (Thaumastus) hartwegi (Pfeiffer in Philippi, 1846); Zebra gruneri Strebel, 1909 = Orthalicus maracaibensis (Pfeiffer, 1856); Scholvienia jaspidea minor Strebel, 1910 = Scholvienia alutacea (Reeve, 1850); Bulimus bifasciatus unicolor Philippi, 1869 = Scholvienia brephoides (d’Orbigny, 1835). A new status is given to Plekocheilus mcgintyi ‘Pilsbry’ H.B. Baker, 1963 (subspecies of Bulinus piperitus Sowerby I, 1837); Strophocheilus superstriatus var. prodeflexus Pilsbry, 1895 (subspecies of Bulinus piperitus Sowerby I, 1837); Thaumastus (Quechua) salteri maximus Weyrauch, 1967 (subspecies of Thaumastus (Quechua) olmosensis Zilch, 1954); Pseudoglandina agitata Weyrauch, 1967 (nomen inquirendum). New combinations are: Clathrorthalicus corydon (Crosse, 1869), and Cyclodontina chuquisacana (Marshall, 1930). Lectotypes are now designated for Bulimus incisus Hupé, 1857 and Bulinus piperitus Sowerby I, 1837. PMID:27408531

  14. Bridging gaps in the molecular phylogeny of the Lymnaeidae (Gastropoda: Pulmonata), vectors of Fascioliasis

    PubMed Central

    2010-01-01

    Background Lymnaeidae snails play a prominent role in the transmission of helminths, mainly trematodes of medical and veterinary importance (e.g., Fasciola liver flukes). As this family exhibits a great diversity in shell morphology but extremely homogeneous anatomical traits, the systematics of Lymnaeidae has long been controversial. Using the most complete dataset to date, we examined phylogenetic relationships among 50 taxa of this family using a supermatrix approach (concatenation of the 16 S, ITS-1 and ITS-2 genes, representing 5054 base pairs) involving both Maximum Likelihood and Bayesian Inference. Results Our phylogenetic analysis demonstrates the existence of three deep clades of Lymnaeidae representing the main geographic origin of species (America, Eurasia and the Indo-Pacific region). This phylogeny allowed us to discuss on potential biological invasions and map important characters, such as, the susceptibility to infection by Fasciola hepatica and F. gigantica, and the haploid number of chromosomes (n). We found that intermediate hosts of F. gigantica cluster within one deep clade, while intermediate hosts of F. hepatica are widely spread across the phylogeny. In addition, chromosome number seems to have evolved from n = 18 to n = 17 and n = 16. Conclusion Our study contributes to deepen our understanding of Lymnaeidae phylogeny by both sampling at worldwide scale and combining information from various genes (supermatrix approach). This phylogeny provides insights into the evolutionary relationships among genera and species and demonstrates that the nomenclature of most genera in the Lymnaeidae does not reflect evolutionary relationships. This study highlights the importance of performing basic studies in systematics to guide epidemiological control programs. PMID:21143890

  15. The Model Organism Hermissenda crassicornis (Gastropoda: Heterobranchia) Is a Species Complex.

    PubMed

    Lindsay, Tabitha; Valdés, Ángel

    2016-01-01

    Hermissenda crassicornis is a model organism used in various fields of research including neurology, ecology, pharmacology, and toxicology. In order to investigate the systematics of this species and the presence of cryptic species in H. crassicornis, we conducted a comprehensive molecular and morphological analysis of this species covering its entire range across the North Pacific Ocean. We determined that H. crassicornis constitutes a species complex of three distinct species. The name Hermissensa crassicornis is retained for the northeast Pacific species, occurring from Alaska to Northern California. The name H. opalescens is reinstated for a species occurring from the Sea of Cortez to Northern California. Finally, the name H. emurai is maintained for the northwestern species, found in Japan and in the Russian Far East. These three species have consistent morphological and color pattern differences that can be used for identification in the field. PMID:27105319

  16. Population biology of the gastropod Olivella minuta (Gastropoda, Olividae) on two sheltered beaches in southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Petracco, Marcelo; Camargo, Rita Monteiro; Tardelli, Daniel Teixeira; Turra, Alexander

    2014-10-01

    The structure, dynamics and production of two populations of the olivid gastropod Olivella minuta were analyzed through monthly sampling from November 2009 through October 2011 on two sandy beaches, Pernambuco (very sheltered) and Barequeçaba (sheltered) in São Paulo state (23°48'S), southeastern Brazil. On both beaches, samples were taken along five transects established perpendicular to the waterline. Parameters of the von Bertalanffy growth function were estimated for both populations from monthly length-frequency distributions. The production and turnover ratios were determined using the mass-specific growth rate method. The population on the less-sheltered Barequeçaba Beach was less abundant (120.02 ± 22.60 ind m-1) than on Pernambuco Beach (3295.30 ± 504.86 ind m-1 (±SE)), which we attribute to the greater environmental stability of the latter. Conversely, the mean length, size of the largest individual, and body mass were higher at Barequeçaba than at Pernambuco. The significant differences in the growth of individuals and the mortality rate (Z) between the beaches suggest that density-dependent processes were operating at Pernambuco Beach. The production and P/B ratio at Pernambuco (12.12 g AFDM m-1 year-1 and 1.91 year-1) were higher than at Barequeçaba (0.82 g AFDM m-1 year-1 and 1.06 year-1). The difference in production can be attributed to the higher abundance on Pernambuco, while the higher P/B ratio resulted from the scarcity of smaller individuals in the intertidal zone of Barequeçaba. The P/B ratio estimated for the Pernambuco population is the highest found so far for sandy-beach gastropods. This study reinforces the theory that biological interactions are important regulators of sheltered sandy-beach populations. Future studies with multi-beach sampling are needed to better understand the life-history variations of O. minuta along gradients of degree of exposure of sandy beaches.

  17. Dynamics and ecology of an Indo-Pacific conch, Conomurex persicus (Mollusca: Gastropoda) in southeastern Turkey.

    PubMed

    Mutlu, Erhan; Ergev, Mehmet Betil

    2006-03-01

    Conomurex persicus, one of the tropical conchs, has been introduced to one of the subtropical regions, the northeastern Mediterranean Sea, and invaded sandy bottoms between 1 and 10 m deep. Population dynamics were studied from specimens collected with a standard dredge (60 x 15 cm mouth opening, 0.5 x 0.5 cm eye opening of net). Samples of C persicus were collected monthly along the 5 and 10 m depth contours off Erdemli, Mersin, Turkey, in February and May 2000. Intra-annual density depended on salinity levels, while inter-annual density was correlated with bottom water temperature. Specimens underwent spring emergences and winter burial and sheltering (disappearance). Emergence took place in March when temperatures rose and the disappearance occurred in October-November when temperatures dropped. Adults live at 10 m, juveniles are recruited at a 5 m depth. Recruitment began in April and continued for the next 6 months. In contrast to shell width or shell lip thickness, shell length was not a convenient index for estimation of growth parameters. Annual production and mortality were calculated to be 7.86 g m(-2) and 3.80 g m(-2), respectively, in April-November.

  18. [Individual growth of Lymnaea stagnalis (Lymnaeidae, Gastropoda): II. Late postlarval ontogeny].

    PubMed

    Zotin, A A

    2009-01-01

    Our investigation on the growth of 14 individuals of the great pond snail Lymnaea stagnalis was performed in an aquatic culture at 18 degrees C beginning from the 10th week after hatching until death. It has been demonstrated that the increase in the mollusk mass follows an S-like curve during the whole studied period. Linear growth (conch height) follows a parabolic (convex) curve until the age of 39 weeks. Both weight and linear growth during studied period significantly approximate to the Bertalanffy equation, while the interrelation between mass and conch height corresponds to the allometric equation. The meanings of the coefficients of these equations do not differ significantly in different individuals. At the age of 38 to 39 weeks, all mollusks demonstrate breakage in the curve of linear growth, then followed with abrupt slowing of growth until stopping or even decreasing in size in some cases. Neither the Bertalanffy equation nor the allometric relation describe the linear growth of individuals with ages exceeding 39 weeks.

  19. [Growth of Strombus gigas (Gastropoda: Strombidae) snail in 4 environments of Quintana Roo, Mexico].

    PubMed

    Navarrete, A J

    2001-03-01

    The growth rate of queen conch cultured in pens was studied from October 1993 to March 1994. Sixteen pens (50 m2 each, four pens per environment), were set in four environments: Thalassia, Thalassia-sand, Sand and Coral within a reef lagoon on Punta Gavilan and Banco Chinchorro. Twenty conchs were introduced in each pen (sizes: 100-120, 120-140, 140-160 and 160-180 mm shell length) and measured monthly to the nearest mm. Growth rate was assessed by two methods: a) shell marginal mean increase and b) the Gulland-Holt method considering all conch within pens. In the first method, the environment Sand had the highest growth (3.21 +/- 0.26 mm/month) at Punta Gavilan, whereas at Banco Chinchorro, highest growth was recorded in Coral (2.31 +/- 0.44 mm/month). Considering the second method, highest asymptotic length conch in Punta Gavilan occurred in Thalassia-sand (287.5 mm), whereas in Banco Chinchorro the highest asymptotic length was measured in Sand (318.1 mm). There were significant differences in growth between sites; juvenile growth is related with habitat quality mainly food availability.

  20. The shallow-water New Caledonia Drilliidae of genus Clavus Montfort, 1810 (Mollusca: Gastropoda: Conoidea).

    PubMed

    Kilburn, Richard N; Fedosov, Alexander; Kantor, Yuri

    2014-06-18

    Species of the genus Clavus of the conoidean family Drilliidae that occur in the littoral and shallow waters of New Caledonia are here revised. This study is based primarily on recent expedition material from the Institut de Recherche pour le Développement (New Caledonia) and Muséum National d'Histoire Naturelle (France). A total of 22 species is recorded, of which eight are described as new. New species: Clavus boucheti, Clavus delphineae, Clavus virginieae, Clavus picoides, Clavus squamiferus, Clavus devexistriatus, Clavus hylikos, Clavus maestratii; New synonyms: Tylotiella Habe, 1958 = Clavus; Clavus leforestieri Hervier, 1896 = Pleurotoma obliquicostata Reeve, 1845; Pleurotoma mariei Crosse, 1869 = Pleurotoma lamberti Montrouzier, 1860; Clavus mighelsi Kay, 1979, new name for Pleurotoma acuminata Mighels, 1845, non J. Sowerby, 1816, was misidentified by Kay 1979; the lectotype of P. acuminata Mighels, 1845, is mangeliine. Clavus mighelsi sensu Kay 1979, is a synonym of Pleurotoma humilis E. A. Smith, 1879. It is suggested that Pleurotoma pulchella Reeve, 1845, sometimes treated as an Indo-Pacific species, may be a senior synonym of Fenimorea halidorema Schwengel, 1940, from the tropical western Atlantic. Nomen dubium: Pleurotoma mediocris Deshayes, 1863.

  1. Patterns of Diversity of the Rissoidae (Mollusca: Gastropoda) in the Atlantic and the Mediterranean Region

    PubMed Central

    Ávila, Sérgio P.; Goud, Jeroen; de Frias Martins, António M.

    2012-01-01

    The geographical distribution of the Rissoidae in the Atlantic Ocean and Mediterranean Sea was compiled and is up-to-date until July 2011. All species were classified according to their mode of larval development (planktotrophic and nonplanktotrophic), and bathymetrical zonation (shallow species—those living between the intertidal and 50 m depth, and deep species—those usually living below 50 m depth). 542 species of Rissoidae are presently reported to the Atlantic Ocean and the Mediterranean Sea, belonging to 33 genera. The Mediterranean Sea is the most diverse site, followed by Canary Islands, Caribbean, Portugal, and Cape Verde. The Mediterranean and Cape Verde Islands are the sites with higher numbers of endemic species, with predominance of Alvania spp. in the first site, and of Alvania and Schwartziella at Cape Verde. In spite of the large number of rissoids at Madeira archipelago, a large number of species are shared with Canaries, Selvagens, and the Azores, thus only about 8% are endemic to the Madeira archipelago. Most of the 542-rissoid species that live in the Atlantic and in the Mediterranean are shallow species (323), 110 are considered as deep species, and 23 species are reported in both shallow and deep waters. There is a predominance of nonplanktotrophs in islands, seamounts, and at high and medium latitudes. This pattern is particularly evident in the genera Crisilla, Manzonia, Onoba, Porosalvania, Schwartziella, and Setia. Planktotrophic species are more abundant in the eastern Atlantic and in the Mediterranean Sea. The results of the analysis of the probable directions of faunal flows support the patterns found by both the Parsimony Analysis of Endemicity and the geographical distribution. Four main source areas for rissoids emerge: Mediterranean, Caribbean, Canaries/Madeira archipelagos, and the Cape Verde archipelago. We must stress the high percentage of endemics that occurs in the isolated islands of Saint Helena, Tristan da Cunha, Cape Verde archipelago and also the Azores, thus reinforcing the legislative protective actions that the local governments have implemented in these islands during the recent years. PMID:22693430

  2. Bisphenol A Induces Superfeminization in the Ramshorn Snail (Gastropoda: Prosobranchia) at Environmentally Relevant Concentrations

    PubMed Central

    Oehlmann, Jörg; Schulte-Oehlmann, Ulrike; Bachmann, Jean; Oetken, Matthias; Lutz, Ilka; Kloas, Werner; Ternes, Thomas A.

    2006-01-01

    Previous investigations have shown that bisphenol A (BPA) induces a superfeminization syndrome in the freshwater snail Marisa cornuarietis at concentrations as low as 1 μg/L. Superfemales are characterized by the formation of additional female organs, enlarged accessory sex glands, gross malformations of the pallial oviduct, and a stimulation of egg and clutch production, resulting in increased female mortality. However, these studies were challenged on the basis of incomplete experimentation. Therefore, the objective of the current approach was to bridge several gaps in knowledge by conducting additional experiments. In an initial series of experiments, study results from the reproductive phase of the snails were evaluated in the sub-micrograms per liter range. Before and after the spawning season, superfemale responses were observed [NOEC (no observed effect concentration) 7.9 ng/L, EC10 (effective concentration at 10%) 13.9 ng/L], which were absent during the spawning season. A further experiment investigated the temperature dependence of BPA responses by exposing snails at two temperatures in parallel. The adverse effect of BPA was at least partially masked at 27°C (EC10 998 ng/L) when compared with 20°C (EC10 14.8 ng/L). In M. cornuarietis, BPA acts as an estrogen receptor (ER) agonist, because effects were completely antagonized by a co-exposure to tamoxifen and Faslodex. Antiandrogenic effects of BPA, such as a significant decrease in penis length at 20°C, were also observed. Competitive receptor displacement experiments indicate the presence of androgen- and estrogen-specific binding sites. The affinity for BPA of the estrogen binding sites in M. cornuarietis is higher than that of the ER in aquatic vertebrates. The results emphasize that prosobranchs are affected by BPA at lower concentrations than are other wildlife groups, and the findings also highlight the importance of exposure conditions. PMID:16818258

  3. New Indo-Pacific species of the genus Teretia Norman, 1888 (Gastropoda: Raphitomidae).

    PubMed

    Morassi, Mauro; Bonfitto, Antonio

    2015-01-01

    Four new species are assigned to the genus Teretia Norman, 1888 in the family Raphitomidae Bellardi, 1875 and herein described: Teretia neocaledonica sp. nov., T. sysoevi sp. nov., T. tongaensis sp. nov. from the southeastern Pacific and Teretia tavianii sp. nov. from the Gulf of Aden. The new species represent the first Indo-Pacific record of a genus previously known in the recent molluscan fauna by only two species from the Atlantic Ocean-Mediterranean Sea and Southern Africa. A possible Tethyan origin for the genus Teretia is suggested.  PMID:25661630

  4. Burnaia Miller, 2001 (Gastropoda, Heterobranchia, Nudibranchia): a facelinid genus with an Aeolidiidae's outward appearance

    NASA Astrophysics Data System (ADS)

    Carmona, Leila; Pola, Marta; Gosliner, Terrence M.; Cervera, Juan Lucas

    2015-09-01

    In recent years, several morphological and molecular analyses have been undertaken to study the phylogenetic systematics of Aeolidiidae members. The monospecific genus Burnaia could not be included in the previous analysis, due to the lack of material. This study includes two specimens of Burnaia helicochorda from Australia and places them in their systematic position using two mitochondrial and one nuclear genes (COI and 16S, and H3, respectively). A description of its anatomy is also included with colour pictures of the animal and scanning electron micrographs of radula and jaws. Based on our results, B. helicochorda does not belong to Aeolidiidae since it appears nested among some facelinids.

  5. The effects of endosulfan on the great ramshorn snail Planorbarius corneus (Gastropoda, Pulmonata): a histopathological study.

    PubMed

    Otludil, Birgül; Cengiz, Elif Ipek; Yildirim, M Zeki; Unver, Ozkan; Unlü, Erhan

    2004-08-01

    In this study the great ramshorn snail (Planorbarius corneus), one of the most abundant gastropod of Turkish limnic systems, was investigated to determine the histopathological effects of endosulfan on the digestive gland, foot and mantle under laboratory conditions. Samples were collected from small artificial pools in Karaot at Gelendost-Isparta (southwest of Turkey), where agricultural activities are widespread. The snails were exposed to two sublethal concentrations of endosulfan (0.4 and 0.8 mg/l) for periods of 10, 20 and 30 days. Fifteen snails were kept in 2.5 l glass jars containing dechlorinated tap water and exposed under semi-static test (daily exchange of test water). All the testing was carried out on adult specimens, and snails were maintained on a photothermal period with 16 light hours at 22 +/- 2 degrees C. The histopathological examinations revealed the following changes: amoebocytes infiltration, dilatation in hemolymphatic spaces between the tubules, degeneration of cells, abnormal lumen, necrosis of cells and atrophy in the connective tissue of digestive gland; desquamation of the epithelium cells, changes in the number of mucocytes and protein gland cells, lipid vacuolus and atrophy of the columnar muscle fibers of the foot and mantle tissues. Pycnotic state of cells was also seen in the mantle tissues. Endosulfan caused significant histopathological alterations in the digestive gland, foot and mantle tissues of the snail, irrespective of concentrations of the pesticide and its exposure periods. The results are discussed, particularly in comparison to those of other aquatic organisms.

  6. Larval trematode infections in Galba truncatula (Gastropoda, Lymnaeidae) from the Brenne Regional Natural Park, central France.

    PubMed

    Rondelaud, D; Vignoles, P; Dreyfuss, G

    2016-05-01

    Adult Galba truncatula ( ≥ 4 mm in shell height) were collected from 135 habitats for 3 years (2012-2014) to identify parasite species via the study of cercariae, and to determine the prevalence of each digenean infection in relation to the type of snail habitat (six types). A total of 323 infected snails and ten digenean species were noted in the bodies of 11,025 G. truncatula after their dissection. Snails with Calicophoron daubneyi and/or Fasciola hepatica were found in 20.7% and 12.5% of the habitats, respectively, and most of these infected snails were collected from rainwater-draining furrows and pools in meadows. The percentages were lower for snails with Echinostoma revolutum (9.6% of habitats) and Haplometra cylindracea (7.4%), and were less than 5% for those parasitized by any of the other five species of digenean. The highest prevalence of all digenean infections was noted in pools (9.4%), followed by furrows located in meadows (8.3%) and ponds (5.1%). The prevalence noted for each digenean infection varied with the type of habitat. In furrows located in meadows, the infection rate of C. daubneyi in snails (3.5%) was significantly higher than that of F. hepatica (2.2%). In pools, values greater than 1.5% were noted for C. daubneyi, H. cylindracea and Opistoglyphe ranae. In ponds, E. revolutum was the dominant species (prevalence, 2.5%). Parasite species richness in G. truncatula was greater in the Brenne Natural Regional Park than in the nearby region of Limousin (ten instead of eight). The distribution and prevalence of each parasite species were dependent on the type and location of each snail habitat.

  7. [Dependence of size of the great ramshorn (Planorbarius corneus L., Gastropoda, Pulmonata) on population density].

    PubMed

    Kirik, E F; Zotin, A A

    2011-01-01

    The dependence of the mean mass (M) of great ramshorn (Planorbarius corneus) individuals on the number of individuals (N) that reached 82-days age in culture with constant conditions--water volume 50 ml, temperature 25 degrees C, and redundant food (dandelion leaves)--has been studied. The relationship between these parameters has been shown to be approximated by the equation M = 139/N mg. Consequently, at least in these conditions the total biomass of same-aged ramshorn individuals in the culture is relatively constant and does not depend on the number of individuals in the population.

  8. The freshwater snails (Gastropoda) of Iran, with descriptions of two new genera and eight new species

    PubMed Central

    Glöer, Peter; Pešić, Vladimir

    2012-01-01

    Abstract Using published records and original data from recent field work and revision of Iranian material of certain species deposited in the collections of the Natural History Museum Basel, the Zoological Museum Berlin, and Natural History Museum Vienna, a checklist of the freshwater gastropod fauna of Iran was compiled. This checklist contains 73 species from 34 genera and 14 families of freshwater snails; 27 of these species (37%) are endemic to Iran. Two new genera, Kaskakia and Sarkhia, and eight species, i.e., Bithynia forcarti, Bithynia starmuehlneri, Bithynia mazandaranensis, Pseudamnicola georgievi, Kaskakia khorrasanensis, Sarkhia sarabensis, Valvata nowsharensis and Acroloxus pseudolacustris are described as new to science; Ecrobia grimmi (Clessin & Dybowski, 1888), Heleobia dalmatica (Radoman, 1974) and Hippeutis complanatus (Linnaeus, 1758) are reported for the first time from Iran. Additional field work is highly desirable for a more appropriate evaluation of the extant freshwater snail biodiversity in Iran. PMID:22977349

  9. Rich and rare—First insights into species diversity and abundance of Antarctic abyssal Gastropoda (Mollusca)

    NASA Astrophysics Data System (ADS)

    Schwabe, Enrico; Michael Bohn, Jens; Engl, Winfried; Linse, Katrin; Schrödl, Michael

    2007-08-01

    The abyssal depths of the polar oceans are thought to be low in diversity compared with the shallower polar shelves and temperate and tropical deep-sea basins. Our recent study on the gastropod fauna of the deep Southern Ocean gives evidence of the existence of a rich gastropod assemblage at abyssal depths. During the ANDEEP I and II expeditions to the southern Drake Passage, Northwestern Weddell Sea, and South Sandwich Trench, gastropods were collected by bottom and Agassiz trawls, epibenthic sledge, and multicorer, at 40 stations in depths between 127 and 5194 m. On the whole, 473 specimens, corresponding to 93 species of 36 families, were obtained. Of those, 414 specimens were caught below 750 m depth and refer to 84 (90%) benthic species of 32 (89%) families. Most families were represented by a single species only. The numerically dominant families were Skeneidae and Buccinidae (with 10 and 11 species, respectively), Eulimidae and Trochidae (with 9 species each), and Turridae (6 species). Thirty-Seven benthic deep-sea species (44%) were represented by a single specimen, and another 20 species (24%) were found at a single station, suggesting that more than two thirds of Antarctic deep-sea gastropod species are very rare or have a very scattered distribution. Of the 27 species occurring at two or more deep-sea stations, 14 were collected with different gear. Approximately half of the deep-water species are new to science or have been recently described. The present investigation increases the total number of recorded benthic Antarctic deep-sea gastropods (below 750 m) from 115 to 177. The previously known depth ranges have been extended, often considerably, for 31 species. The collected deep-sea gastropods comprise both eurybathic shelf species (29%) and apparently true deep-sea species (58%); some of the latter may belong to a so far unknown Antarctic abyssal fauna. Geographical ranges of the collected Antarctic benthic deep-sea gastropod species appear limited, and all these 84 species seem endemic to Antarctica south of the Polar Front. Comparing diversity and abundances based on epibenthic sledge samples, there is no clear relationship between Antarctic deep-sea gastropod abundance and species richness with depth. However, both Antarctic and adjacent deep-sea areas are still far from being adequately sampled to allow more comprehensive conclusions.

  10. Mitochondrial genome of the endangered marine gastropod Strombus gigas Linnaeus, 1758 (Mollusca: Gastropoda).

    PubMed

    Márquez, Edna J; Castro, Erick R; Alzate, Juan F

    2016-01-01

    The queen conch Strombus gigas is an endangered marine gastropod of significant economic importance across the Greater Caribbean region. This work reports for the first time the complete mitochondrial genome of S. gigas, obtained by FLX 454 pyrosequencing. The mtDNA genome encodes for 13 proteins, 22 tRNAs and 2 ribosomal RNAs. In addition, the coding sequences and gene synteny were similar to other previously reported mitogenomes of gastropods.

  11. A new Middle Miocene Niveria Jousseaume, 1884 (Mollusca: Gastropoda: Trivioidea) from Hungary

    NASA Astrophysics Data System (ADS)

    Fehse, Dirk

    2011-02-01

    A new species of Niveria from the Middle Miocene (Badenian) of the Paratethys of Borsodbóta, Hungary is described. This species is characterized by its callused dorsum and dorsal depression. Niveria jozefgregoi sp. nov. is discussed with comparative species from the Badenian of Hungary, the Pliocene of the Mediterranean region, Florida and Recent species from Madeira and the Islas Galápagos.

  12. [Morphobiochemical adaptations of Mediterranean Littorina punctata (Gmelin, 1790) (Mollusca, Gastropoda) to survival under supralittoral conditions].

    PubMed

    Aliakrinskaia, I O

    2014-01-01

    Behavioral and morphobiochemical adaptations of Littorina punctata to dwelling under supralittoral condi- tions are analyzed. A quantitative estimation of the hemoglobin content in the radular tissues of the mollusk is given.

  13. Family matters: The first molecular phylogeny of the Onchidorididae Gray, 1827 (Mollusca, Gastropoda, Nudibranchia).

    PubMed

    Hallas, Joshua M; Gosliner, Terrence M

    2015-07-01

    Recent investigations into the evolution of the Onchidorididae using morphological based methods have resulted in low support for relationships among genera. This study aims to determine if molecular data corroborates recent morphological interpretations of the evolution of Onchidorididae. Five genetic markers: 16S, 18S, 28S, cytochrome c oxidase 1 (COI) and histone 3 (H3), were sequenced from 32 species comprising Onchidorididae and five other families, three from Phanerobranchia and two from Cryptobranchia. Phylogenies were estimated using maximum likelihood, and Bayesian inference analyses; with both yielding similar topologies. Molecular analyses resulted in high support for the monophyly of the suctorian clade and the placement of the genera within Onchidorididae. However, the Onchidorididae forms a paraphyletic grouping due to the recovery of the Goniodorididae and the Akiodorididae nested within family. In addition, the placement of Corambe as the most derived member of Onchidorididae is contradicted by the present study. Rather it is sister to a large clade that includes Acanthodoris and the species traditionally placed in Onchidoris and Adalaria, now defined as Onchidorididae. We have chosen to maintain Corambidae as a distinct taxon (including Corambe and Loy), sister to Onchidorididae. We also maintain Goniodorididae, Akiodorididae and Calycidoridae (including Calycidoris and Diaphorodoris), which along with the Onchidorididae and Corambidae comprise the suctorian superfamily Onchidoridoidea. Ancestral character reconstruction also suggests that the formation of a gill pocket, a character that currently defines the Cryptobranchia, may have evolved multiple times from an ancestor that lacked the ability to retract its gills into a fully formed gill pocket. The diversity of gill morphology displayed by the Onchidoridoidea will help give new insight into the evolution of this complex character within the Nudibranchia.

  14. Quantification of midkine gene expression in Patella caerulea (Mollusca, Gastropoda) exposed to cadmium

    NASA Astrophysics Data System (ADS)

    Stillitano, Francesca; Mugelli, Alessandro; Cerbai, Elisabetta; Vanucci, Silvana

    2007-10-01

    The release of cadmium into many coastal areas represents a threat to ecosystems and human health; cadmium is carcinogenic in mammals and in both marine invertebrates and vertebrates. The use of molluscs to assess the ecologic risk associated with contaminants is strongly recommended on account of their ecological role and on their highly conserved control and regulatory pathways that are often homologous to vertebrate systems. We previously identified a midkine family protein in the limpet Patella caerulea; the midkine is a recently discovered cytokines family with unequivocal informative value on repairing injury and neoplastic processes in mammals. Here we report on midkine ( mdk) and α-tubulin ( α-tub) gene expression patterns in P. caerulea exposed to cadmium. Limpets, collected on two occasions from a breakwater at a marina (Tyrrhenian Sea) were exposed to sublethal cadmium concentrations (0.5 and 1 mg l -1 Cd) over a 10-day exposure period. RNA was extracted from the viscera of unexposed and exposed specimens. Real time TaqMan RT-PCR was performed to measure the relative mdk and α-tub gene expression levels. A remarkable mdk over-expression was observed in all exposed animals with respect to unexposed ones; mdk over-expression was significantly higher in both treatments when compared with un-treatment (mean expression levels: 23- and 38-fold, for 0.5 and 1 mg l -1 Cd treatment, respectively; ANOVA, for both P < 0.01). The study also indicates that the mdk up-regulation was significantly Cd-concentration dependent ( P < 0.05). A significant up-regulation of the constitutive α-tub gene was also observed in 1 mg l -1 Cd-treated animals (mean expression level: 4-fold; ANOVA, P < 0.05). In conclusion, these data provide the first evidence paving the way for the use of the midkine as a promising new biomarker of effect in the environment risk assessment policy.

  15. Unusual micrometric calcite-aragonite interface in the abalone shell Haliotis (Mollusca, Gastropoda).

    PubMed

    Dauphin, Yannicke; Cuif, Jean-Pierre; Castillo-Michel, Hiram; Chevallard, Corinne; Farre, Bastien; Meibom, Anders

    2014-02-01

    Species of Haliotis (abalone) show high variety in structure and mineralogy of the shell. One of the European species (Haliotis tuberculata) in particular has an unusual shell structure in which calcite and aragonite coexist at a microscale with small patches of aragonite embedded in larger calcitic zones. A detailed examination of the boundary between calcite and aragonite using analytical microscopies shows that the organic contents of calcite and aragonite differ. Moreover, changes in the chemical composition of the two minerals seem to be gradual and define a micrometric zone of transition between the two main layers. A similar transition zone has been observed between the layers in more classical and regularly structured mollusk shells. The imbrication of microscopic patches of aragonite within a calcitic zone suggests the occurrence of very fast physiological changes in these taxa.

  16. Unraveling the evolutionary history of the Chilostoma Fitzinger, 1833 (Mollusca, Gastropoda, Pulmonata) lineages in Greece.

    PubMed

    Psonis, Nikolaos; Vardinoyannis, Katerina; Mylonas, Moisis; Poulakakis, Nikos

    2015-10-01

    The land snails of the genus Chilostoma Fitzinger, 1833 that includes, in Greece, the (sub)genera Cattania, Josephinella and Thiessea, are highly diversified and present high levels of endemism. However, their evolutionary history is unknown and their taxonomy is complex and continuously revised. The aim of this study is to investigate the phylogenetic relationships of the lineages of the genus Chilostoma distributed in Greece based on partial DNA sequences of two mitochondrial DNA (16S rRNA and COI) genes. Complete sequences of one nuclear gene (ITS1) representing the major mitochondrial lineages were also analyzed. The phylogenetic trees revealed three distinct major clades that correspond to the three (sub)genera. Several taxonomical incongruencies were made obvious, thus, raising questions about the "true" number of species in each clade, while rendering a taxonomic re-evaluation necessary. From a phylogeographic point of view, it seems that the three major phylogenetic clades were separated in the late Miocene. They started differentiating into distinct species during the Pliocene and Pleistocene through several vicariance and dispersal events.

  17. Patterns of diversity of the Rissoidae (Mollusca: Gastropoda) in the Atlantic and the Mediterranean region.

    PubMed

    Ávila, Sérgio P; Goud, Jeroen; de Frias Martins, António M

    2012-01-01

    The geographical distribution of the Rissoidae in the Atlantic Ocean and Mediterranean Sea was compiled and is up-to-date until July 2011. All species were classified according to their mode of larval development (planktotrophic and nonplanktotrophic), and bathymetrical zonation (shallow species--those living between the intertidal and 50 m depth, and deep species--those usually living below 50 m depth). 542 species of Rissoidae are presently reported to the Atlantic Ocean and the Mediterranean Sea, belonging to 33 genera. The Mediterranean Sea is the most diverse site, followed by Canary Islands, Caribbean, Portugal, and Cape Verde. The Mediterranean and Cape Verde Islands are the sites with higher numbers of endemic species, with predominance of Alvania spp. in the first site, and of Alvania and Schwartziella at Cape Verde. In spite of the large number of rissoids at Madeira archipelago, a large number of species are shared with Canaries, Selvagens, and the Azores, thus only about 8% are endemic to the Madeira archipelago. Most of the 542-rissoid species that live in the Atlantic and in the Mediterranean are shallow species (323), 110 are considered as deep species, and 23 species are reported in both shallow and deep waters. There is a predominance of nonplanktotrophs in islands, seamounts, and at high and medium latitudes. This pattern is particularly evident in the genera Crisilla, Manzonia, Onoba, Porosalvania, Schwartziella, and Setia. Planktotrophic species are more abundant in the eastern Atlantic and in the Mediterranean Sea. The results of the analysis of the probable directions of faunal flows support the patterns found by both the Parsimony Analysis of Endemicity and the geographical distribution. Four main source areas for rissoids emerge: Mediterranean, Caribbean, Canaries/Madeira archipelagos, and the Cape Verde archipelago. We must stress the high percentage of endemics that occurs in the isolated islands of Saint Helena, Tristan da Cunha, Cape Verde archipelago and also the Azores, thus reinforcing the legislative protective actions that the local governments have implemented in these islands during the recent years.

  18. New distribution record for the rare limpet Acroloxus coloradensis (Henderson) (Gastropoda: Acroloxidae) from Montana

    USGS Publications Warehouse

    Hossack, Blake R.; Robert L. Newell,

    2013-01-01

    The Rocky Mountain Capshell, Acroloxus coloradensis (Henderson, 1930), the only North American member of the basommatophoran family Acroloxidae, is broadly distributed across southern Canada and south into the Rocky Mountains in the USA (Turgeon et al., 1998; Lee and Ackerman, 2000). Despite its wide geographic range, A. coloradensis has been documented from < 30 locations, mostly in British Columbia, Alberta, Ontario, and Quebec (Lee and Ackerman, 2000; Anderson, 2005). Relict populations of A. coloradensis in the USA have been documented from only 6 sites in Colorado and 2 sites in Glacier National Park (Glacier NP), Montana (Anderson, 2005; Ellis et al., 2004). In Glacier NP, A. coloradensis was first reported from Lost Lake (Figure 1; Russell and Brunson, 1967). A second population in the park was discovered in Trout Lake in 2001 (Ellis et al., 2004). In both lakes, A. coloradensis was found primarily under rocks and other cover objects.

  19. Bacteriological and biochemical assessment of marinating cephalopods, crustaceans and gastropoda during 24 weeks of storage.

    PubMed

    Ozogul, Yesim; Ozogul, Fatih; Olgunoglu, Ilkan A; Kuley, Esmeray

    2008-09-01

    The quality and safety parameters of mixed marinated seafood salad containing common octopus (Octopus vulgaris), shrimp (Parapenaeus longirostris), European squid (Loligo vulgaris), sea snail (Rapana thomasiana) and common cuttlefish (Sepia officinalis) at 4 degrees C during storage of 24 weeks were investigated. In addition, the nutritional value in terms of proximate and fatty acid composition of seafood salad was also determined. Sensory scores of seafood salad in terms of appearance, odour, flavour and texture slightly decreased throughout the storage period. However, at the end of the storage period (5 months), the marinated seafood salad was still acceptable by the panellist. At the beginning of storage the total volatile basic nitrogen (TVB-N) value was 6.05 mg/100 g flesh, and the TVB-N values rose to 11.19 mg TVB-N/flesh by the end of the storage period. The pH value of the marinated seafood salad showed fluctuations, ranging from 3.57 to 3.65, and did not change significantly during the storage period. The concentrations of the biogenic amines in both the muscle of all species and in the solution of salad were also investigated. Among the biogenic amines, histamine was not detected in all samples throughout the storage period. The putrescine and cadaverine levels increased throughout the storage period, with a lower increase in the solution of seafood salad. Salmonella, coliform, Escherichia coli and Staphylococcus aureus were not detected while the total viable count remained low (3 log CFU/g) after 3 months of storage.

  20. Short-term climate change and the extinction of the snail Rhachistia aldabrae (Gastropoda: Pulmonata).

    PubMed

    Gerlach, Justin

    2007-10-22

    The only known population of the Aldabra banded snail Rhachistia aldabrae declined through the late twentieth century, leading to its extinction in the late 1990s. This occurred within a stable habitat and its extinction is attributable to decreasing rainfall on Aldabra atoll, associated with regional changes in rainfall patterns in the late twentieth and early twenty-first century. It is proposed that the extinction of this species is a direct result of decreasing rainfall leading to increased mortality of juvenile snails.

  1. Population ecology and fishery of Cittarium pica (Gastropoda: Trochidae) on the Caribbean coast of Costa Rica.

    PubMed

    Schmidt, Stefanie; Wolff, Matthias; Vargas, José A

    2002-01-01

    The West Indian Topshell Cittarium pica is artisanally collected on rocky shores along the Caribbean Coast of Costa Rica. There are neither data on the state of its exploitation nor exist any regulation of the fishery From October 2000 to March 2001, the population dynamics of this species were studied at an unexploited and two exploited sites to determine the present impact of the fishery on the resource. Average population density with 14 ind./m2 about three times higher at the unexploited than at the exploited sites. Length-frequency histograms showed a strong shift towards smaller specimens at the exploited sites, which is also reflected in significantly higher rates of total mortality (Z = 4.05 and 4.47) when compared to the unexploited site (Z = 1.47). Von Bertalanffy growth parameters were estimated as k = 0.19-0.28 (yr-1) and L infinity = 104 mm. No significant differences were found among sites. From these values a range of the growth performance index phi was computed (phi = 3.31-3.48) which lies at the lower end of the values reported for other tropical marine gastropods. The size at first maturity for both sexes combined was estimated as 29.20 +/- 1.14 mm. Exploitation rates > 0.6 for both exploited sites and a large fraction of small specimens (< 30 mm) in the catches suggest overexploitation and recruitment overfishing. Based on the estimated maximum sustainable yield we recommend regulative measures for the fishery such as a control of a minimum landing size of 40 mm and a closure of the fishery during its reproductive period (from July to November).

  2. Caribbean Bulimulus revisited: physical moves and molecular traces (Mollusca, Gastropoda, Bulimulidae).

    PubMed

    Breure, Abraham S H

    2016-01-01

    Twenty-five samples of Bulimulus species are studied, partly from localities within their known distribution range, partly based on interceptions where the material originates from localities where the species seem to be recently introduced and non-native. Molecular study of cytochrome oxidase 1 (CO1) reveals the origin of some of these introductions, but is less conclusive for others. Four different methods for species delimitation were applied, which did not result in unambiguous species hypotheses. For a rapid identification of morphologically indistinct species, a more comprehensive database of sequences is needed. PMID:27069787

  3. New taxa of terrestrial molluscs from Turkey (Gastropoda, Pristilomatidae, Enidae, Hygromiidae, Helicidae)

    PubMed Central

    Gümüş, Burçin Aşkım; Neubert, Eike

    2012-01-01

    Abstract This paper reports on results of several collecting trips of the authors in Turkey. In the course of this research, a long-lasting question was addressed. It could be proven that the nominal species Bulimus frivaldskyi L. Pfeiffer, 1847 is closely related to Meijeriella canaliculata Bank, 1985, and thus this species is shifted from the genus Ena Turton, 1831, to the genus Meijeriella Bank, 1985. Meijeriella canaliculata Bank, 1985, could be recorded from Turkey for the first time. The nomenclatural situation of the species Euchondrus septemdentatus (Roth, 1839) vs. its replacement name Euchondrus borealis (Mousson, 1874) is discussed. A new arrangement of the species formely comprised in the genus Zebrina Held, 1837 is presented, and the genera Rhabdoena Kobelt & Moellendorff, 1902, and Leucomastus A. Wagner, 1927 are re-established. The following species and subspecies new to science could be described: Vitrea gostelii sp. n. (Pristilomatidae), Turanena demirsoyi sp. n., Euchondrus paucidentatus sp. n., Rhabdoena gostelii sp. n. (all Enidae), Metafruticicola kizildagensis sp. n. (Hygromiidae), and Assyriella thospitis menkhorsti ssp. n. (Helicidae). For several other species, new distribution records are listed. PMID:22423194

  4. New species of the genus Elachisina (Gastropoda: Elachisinidae) from northeastern Brazil.

    PubMed

    Cunha, Carlo M; Santos, Franklin N; Lima, Silvio F B

    2016-01-01

    The family Elachisinidae Ponder, 1985 includes minute marine gastropods that live predominantly in the sublittoral zone (Ponder & Keyzer 1998; Rolán & Rubio 2001; Rolán & Gofas 2003). Most elachisinids have been included in the genus Elachisina Dall, 1918 based on their shell morphology (Warén 1996; Rolán & Rubio 2001; Rolán & Gofas 2003), consequently, very little is known about the habitat and ecological niche of the species (Ponder & Keyzer 1998; Rolán & Gofas 2003). Elachisina floridana (Rehder, 1943) is the only Atlantic congener collected alive, and is known to live beneath rocks and in rocky crevices in the intertidal zone to about 1 m depth in the Bahamas and Caribbean Sea (Ponder 1985; Ponder & Keyzer 1998; Rolán & Gofas 2003; Redfern 2013). Eastern Atlantic E. canarica (Nordsieck & García-Talavera, 1979) was also collected alive from the Canary Islands, but with no information on the habitat (Rolán & Gofas 2003). The islands of the northeastern Atlantic and West Africa are the regions with the greatest Elachisina richness known, totaling nine species (Rolán & Rubio 2001; Rolán & Gofas 2003). Only E. floridana has been recognized so far to be widely distributed throughout the Western Atlantic (Rolán & Gofas 2003; Rios 2009; Redfern 2013). PMID:27470791

  5. A phylogeny for the pomatiopsidae (Gastropoda: Rissooidea): a resource for taxonomic, parasitological and biodiversity studies

    PubMed Central

    2014-01-01

    Background The Pomatiopsidae are reported from northern India into southern China and Southeast Asia, with two sub-families, the Pomatiopsinae (which include freshwater, amphibious, terrestrial and marine species) and the freshwater Triculinae. Both include species acting as intermediate host for species of the blood-fluke Schistosoma which cause a public health problem in East Asia. Also, with around 120 species, triculine biodiversity exceeds that of any other endemic freshwater molluscan fauna. Nevertheless, the origins of the Pomatiopsidae, the factors driving such a diverse radiation and aspects of their co-evolution with Schistosoma are not fully understood. Many taxonomic questions remain; there are problems identifying medically relevant species. The predicted range is mostly unsurveyed and the true biodiversity of the family is underestimated. Consequently, the aim of the study was to collect DNA-sequence data for as many pomatiopsid taxa as possible, as a first step in providing a resource for identification of epidemiologically significant species (by non-malacologists), for use in resolving taxonomic confusion and for testing phylogeographical hypotheses. Results The evolutionary radiation of the Triculinae was shown to have been rapid and mostly post late Miocene. Molecular dating indicated that the radiation of these snails was driven first by the uplift of the Himalaya and onset of a monsoon system, and then by late-Pliocene global warming. The status of Erhaia as Anmicolidae is supported. The genera Tricula and Neotricula are shown to be non-monophyletic and the tribe Jullieniini may be polyphyletic (based on convergent characters). Triculinae from northern Vietnam could be derived from Gammatricula of Fujian/Yunnan, China. Conclusions The molecular dates and phylogenetic estimates in this study are consistent with an Australasian origin for the Pomatiopsidae and an East to West radiation via Oligocene Borneo-Philippines island hopping to Japan and then China (Triculinae arising mid-Miocene in Southeast China), and less so with a triculine origin in Tibet. The lack of monophyly in the medically important genera and indications of taxonomic inaccuracies, call for further work to identify epidemiologically significant taxa (e.g., Halewisia may be potential hosts for Schistosoma mekongi) and highlight the need for surveys to determine the true biodiversity of the Triculinae. PMID:24548800

  6. Late Paleozoic subulitacea (mollusca:gastropoda), mass extinctions and the replacement of evolutionary faunas

    SciTech Connect

    Erwin, D.H.

    1985-01-01

    Mesogastropod subulitaceans possess characteristics typical of active carnivores and occupied a trophic regime typical of the Mesozoic-Cenozoic evolutionary fauna. Despite occupying a vacant niche, subulitaceans are low in both diversity and abundance in late Paleozoic gastropod faunas. In addition, Paleozoic Archaeogastropoda and Mesogastropoda are taxonomically and functionally distinct from Mesozoic groups and display diversity dynamics typical of the Paleozoic evolutionary fauna, not the Mesozoic-Cenozoic fauna with which they were grouped by Sepkoski. Late Paleozoic gastropods are different from pre-Carboniferous taxa, but there is no preferential expansion of the major Mesozoic taxa, nor is there any pattern of exploitation of a major niche utilized by later groups but under-used by Paleozoic taxa. The high taxonomic level used Sepkoski's factor analysis neglects the finer scale of replacement and diversification. This distinct evolutionary behavior of Paleozoic gastropods may be typical of other taxa as well. It weakens the assertions of Kitchell and Carr and Sepkoksi and Miller that the replacement of evolutionary Fauna II by Fauna III began in the late Paleozoic and would have occurred even without the Guadelupian-Dzulfian mass extinction. Thus for gastropods at last, the Late Permian mass extinction did not merely speed up on ongoing process, but probably determined the evolutionary outcome.

  7. Genetic diversity, fixation and differentiation of the freshwater snail Biomphalaria pfeifferi (Gastropoda, Planorbidae) in arid lands.

    PubMed

    Mintsa Nguema, Rodrigue; Langand, Juliette; Galinier, Richard; Idris, Mohamed A; Shaban, Mahmoud A; Al Yafae, Salem; Moné, Hélène; Mouahid, Gabriel

    2013-06-01

    The freshwater snail Biomphalaria pfeifferi is the main intermediate host of human intestinal Bilharziasis. It is widely distributed in Africa, Madagascar and middle-eastern countries, and its habitat includes wetlands, and arid to semi-arid areas. Based on analysis of 18 microsatellites, we investigated reference allelic variation among 30 populations of B. pfeifferi from three drainage basins in Dhofar, Oman (the eastern limit of its distribution). This is an arid to semi-arid region, with a 9,000-year history of very low rainfall, but is subject to unpredictable and destructive flash floods. In this context we showed that genetic fixation was very high compared to genetic differentiation which was moderate and, that, relative to B. pfeifferi populations from wetlands, the populations in Dhofar show evidence of lower levels of genetic diversity, a higher degree of genetic fixation, a quasi-absence of migration, and a higher level of genetic drift. Despite the extreme conditions in the Dhofar habitat of this species, it is able to survive because of its very high self-fertilization (approaching 100 %) and fecundity rates.

  8. [Individual growth of Lymnaea stagnalis (Lymnaeidae, Gastropoda): II. Late postlarval ontogeny].

    PubMed

    Zotin, A A

    2009-01-01

    Our investigation on the growth of 14 individuals of the great pond snail Lymnaea stagnalis was performed in an aquatic culture at 18 degrees C beginning from the 10th week after hatching until death. It has been demonstrated that the increase in the mollusk mass follows an S-like curve during the whole studied period. Linear growth (conch height) follows a parabolic (convex) curve until the age of 39 weeks. Both weight and linear growth during studied period significantly approximate to the Bertalanffy equation, while the interrelation between mass and conch height corresponds to the allometric equation. The meanings of the coefficients of these equations do not differ significantly in different individuals. At the age of 38 to 39 weeks, all mollusks demonstrate breakage in the curve of linear growth, then followed with abrupt slowing of growth until stopping or even decreasing in size in some cases. Neither the Bertalanffy equation nor the allometric relation describe the linear growth of individuals with ages exceeding 39 weeks. PMID:20143629

  9. Mitochondrial genome of the endangered marine gastropod Strombus gigas Linnaeus, 1758 (Mollusca: Gastropoda).

    PubMed

    Márquez, Edna J; Castro, Erick R; Alzate, Juan F

    2016-01-01

    The queen conch Strombus gigas is an endangered marine gastropod of significant economic importance across the Greater Caribbean region. This work reports for the first time the complete mitochondrial genome of S. gigas, obtained by FLX 454 pyrosequencing. The mtDNA genome encodes for 13 proteins, 22 tRNAs and 2 ribosomal RNAs. In addition, the coding sequences and gene synteny were similar to other previously reported mitogenomes of gastropods. PMID:25186797

  10. [Growth of Strombus gigas (Gastropoda: Strombidae) snail in 4 environments of Quintana Roo, Mexico].

    PubMed

    Navarrete, A J

    2001-03-01

    The growth rate of queen conch cultured in pens was studied from October 1993 to March 1994. Sixteen pens (50 m2 each, four pens per environment), were set in four environments: Thalassia, Thalassia-sand, Sand and Coral within a reef lagoon on Punta Gavilan and Banco Chinchorro. Twenty conchs were introduced in each pen (sizes: 100-120, 120-140, 140-160 and 160-180 mm shell length) and measured monthly to the nearest mm. Growth rate was assessed by two methods: a) shell marginal mean increase and b) the Gulland-Holt method considering all conch within pens. In the first method, the environment Sand had the highest growth (3.21 +/- 0.26 mm/month) at Punta Gavilan, whereas at Banco Chinchorro, highest growth was recorded in Coral (2.31 +/- 0.44 mm/month). Considering the second method, highest asymptotic length conch in Punta Gavilan occurred in Thalassia-sand (287.5 mm), whereas in Banco Chinchorro the highest asymptotic length was measured in Sand (318.1 mm). There were significant differences in growth between sites; juvenile growth is related with habitat quality mainly food availability. PMID:11795173

  11. Dynamics and ecology of an Indo-Pacific conch, Conomurex persicus (Mollusca: Gastropoda) in southeastern Turkey.

    PubMed

    Mutlu, Erhan; Ergev, Mehmet Betil

    2006-03-01

    Conomurex persicus, one of the tropical conchs, has been introduced to one of the subtropical regions, the northeastern Mediterranean Sea, and invaded sandy bottoms between 1 and 10 m deep. Population dynamics were studied from specimens collected with a standard dredge (60 x 15 cm mouth opening, 0.5 x 0.5 cm eye opening of net). Samples of C persicus were collected monthly along the 5 and 10 m depth contours off Erdemli, Mersin, Turkey, in February and May 2000. Intra-annual density depended on salinity levels, while inter-annual density was correlated with bottom water temperature. Specimens underwent spring emergences and winter burial and sheltering (disappearance). Emergence took place in March when temperatures rose and the disappearance occurred in October-November when temperatures dropped. Adults live at 10 m, juveniles are recruited at a 5 m depth. Recruitment began in April and continued for the next 6 months. In contrast to shell width or shell lip thickness, shell length was not a convenient index for estimation of growth parameters. Annual production and mortality were calculated to be 7.86 g m(-2) and 3.80 g m(-2), respectively, in April-November. PMID:18457181

  12. Intraspecific and interspecific chemoattraction inBiomphalaria glabrata andHelisoma trivolvis (Gastropoda: Planorbidae).

    PubMed

    Marcopoulos, A A; Fried, B

    1994-10-01

    A Petri dish bioassay previously used to examine food preferences in planorbid snails was used to study intraspecific and interspecific chemoattraction inBiomphalaria glabrata (albino strain, M-line) andHelisoma trivolvis (Colorado strain) snails.B. glabrata snails showed significant intraspecific chemoattraction in the absence of visual cues and snail thigmotaxis.H. trivolvis snails also showed significant intraspecific chemoattraction. Interspecific chemoattraction between these species occurred in the bioassay, suggesting that the chemoattractants were not species specific. Artificial spring water conditioned by aqueous excretory-secretory products (snail-conditioned water) ofB. glabrata elicited significant intraspecific chemoattraction. However, lipophilic excretory-secretory products ofB. glabrata elicited significant chemorepulsion. Repellant factors in the lipophilic fraction were not characterized. PMID:24241838

  13. DNA barcoding reveals neritid diversity (Mollusca: Gastropoda) diversity in Malaysian waters.

    PubMed

    Chee, S Y; Mohd Nor, Siti Azizah

    2016-05-01

    This is the first study to identify and determine the phylogenetics of neritids found in Malaysia. In total, twelve species from the family Neritidae were recorded. Ten species were from the genus Nerita and two species were from the genus Neritina. DNA barcodes were successfully assigned to each species. Although some of these species were previously reported in the region, three are only presently reported in this study. The dendrogram showed Nerita and Neritina strongly supported in their respective monophyletic clades. Phylogenetic positions of some species appeared unstable in the trees. This could be due to the differences in a small number of nucleotides, thus minimizing genetic variation between each specimen and species.

  14. Severnsia strombeulima n. gen. & sp. from Hawaii (Mollusca, Gastropoda: Caenogastropoda: Eulimidae).

    PubMed

    Geiger, Daniel L

    2016-01-01

    The malacofauna of Hawaii is rather well-known, owing to Kay (1979) and Severns (2011). Both works stand out because they include a large number of the generally under-represented micromollusks (<5 mm). Here a striking new genus and species of a microsnail is reported from that region.

  15. Prestonellinae-validation of the name as a new subfamily of Bothriembryontidae (Mollusca, Gastropoda, Orthalicoidea).

    PubMed

    Bruggen, A C Van; Herbert, David G; Breure, Abraham S H

    2016-01-01

    The affinities of the enigmatic South African land snail genus Prestonella Connolly, 1929 were discussed by Herbert (2007) and Herbert & Mitchell (2009), who showed, on the basis of morphological and molecular data, that the genus is referable to the superfamily Orthalicoidea. Currently, the three described species of Prestonella are the only known African representatives of this diverse superfamily. Earlier, van Bruggen (1978) had recognized that these species formed a distinct group and had placed them in the (new) family Prestonellidae. However, as noted by Bouchet & Rocroi (2005: 140), no diagnosis was provided by van Bruggen; the name Prestonellidae thus does not meet the requirements of ICZN Art. 13.1, and is not an available name. In this paper we will redress this issue, also taking into account more recent research which has shed light on the systematic position of this genus within the Orthalicoidea.

  16. A new species of Bothriembryon (Mollusca, Gastropoda, Bothriembryontidae) from south-eastern Western Australia.

    PubMed

    Whisson, Corey S; Breure, Abraham S H

    2016-01-01

    Bothriembryon sophiarum sp. n. is described, based on shell and anatomical morphology, from the coastal area of south-easternmost Western Australia. This is the first description of a new extant Australian bothriembryontid in 33 years. The shell of Bothriembryon sophiarum is slender with a unique teleoconch sculpture. It is found in low coastal scrub on cliff edges and escarpments and because of its restricted distribution, qualifies as a short range endemic.

  17. Molecular data for Crenavolva species (Gastropoda, Ovulidae) reveals the synonymy of C. chiapponii

    PubMed Central

    Reijnen, Bastian T.

    2015-01-01

    Abstract During fieldwork in Indonesia and Malaysia, eight lots containing 33 specimens belonging to the genus Crenavolva (Ovulidae) were collected. Species were initially identified as Crenavolva aureola, Crenavolva chiapponii, Crenavolva striatula and Crenavolva trailli, respectively. For Crenavolva chiapponii this is the second record. In contrast to the ecological data available from the original description of this species, it was found in shallow water on a gorgonian host coral, i.e. Acanthogorgia sp. A molecular analysis based on COI and 16S mtDNA markers, including sequence data obtained from GenBank, showed that Crenavolva chiapponii should be considered a junior synonym of Crenavolva aureola and that previously identified ovulid specimens are probably misidentified. PMID:25987877

  18. New Indo-Pacific species of the genus Teretia Norman, 1888 (Gastropoda: Raphitomidae).

    PubMed

    Morassi, Mauro; Bonfitto, Antonio

    2015-01-21

    Four new species are assigned to the genus Teretia Norman, 1888 in the family Raphitomidae Bellardi, 1875 and herein described: Teretia neocaledonica sp. nov., T. sysoevi sp. nov., T. tongaensis sp. nov. from the southeastern Pacific and Teretia tavianii sp. nov. from the Gulf of Aden. The new species represent the first Indo-Pacific record of a genus previously known in the recent molluscan fauna by only two species from the Atlantic Ocean-Mediterranean Sea and Southern Africa. A possible Tethyan origin for the genus Teretia is suggested. 

  19. Annotated type catalogue of the Bulimulidae (Mollusca, Gastropoda, Orthalicoidea) in the Natural History Museum, London

    PubMed Central

    Breure, Abraham S.H.; Ablett, Jonathan D.

    2014-01-01

    Abstract The type status is described of 404 taxa classified within the family Bulimulidae (superfamily Orthalicoidea) and kept in the London museum. Lectotypes are designated for Bulimus aurifluus Pfeiffer, 1857; Otostomus bartletti H. Adams, 1867; Helix cactorum d’Orbigny, 1835; Bulimus caliginosus Reeve, 1849; Bulimus chemnitzioides Forbes, 1850; Bulimus cinereus Reeve, 1849; Helix cora d’Orbigny, 1835; Bulimus fallax Pfeiffer, 1853; Bulimus felix Pfeiffer, 1862; Bulimus fontainii d’Orbigny, 1838; Bulimus fourmiersi d’Orbigny, 1837; Bulimus (Mesembrinus) gealei H. Adams, 1867; Bulimus gruneri Pfeiffer, 1846; Bulimus humboldtii Reeve, 1849; Helix hygrohylaea d’Orbigny, 1835; Bulimus jussieui Pfeiffer, 1846; Bulimulus (Drymaeus) binominis lascellianus E.A. Smith, 1895; Helix lichnorum d’Orbigny, 1835; Bulimulus (Drymaeus) lucidus da Costa, 1898; Bulimus luridus Pfeiffer, 1863; Bulimus meleagris Pfeiffer, 1853; Bulimus monachus Pfeiffer, 1857; Bulimus montagnei d’Orbigny, 1837; Helix montivaga d’Orbigny, 1835; Bulimus muliebris Reeve, 1849; Bulimus nigrofasciatus Pfeiffer in Philippi 1846; Bulimus nitelinus Reeve, 1849; Helix oreades d’Orbigny, 1835; Helix polymorpha d’Orbigny, 1835; Bulimus praetextus Reeve, 1849; Bulinus proteus Broderip, 1832; Bulimus rusticellus Morelet, 1860; Helix sporadica d’Orbigny, 1835; Bulimus sulphureus Pfeiffer, 1857; Helix thamnoica var. marmorata d’Orbigny, 1835; Bulinus translucens Broderip in Broderip and Sowerby I 1832; Helix trichoda d’Orbigny, 1835; Bulinus ustulatus Sowerby I, 1833; Bulimus voithianus Pfeiffer, 1847; Bulimus yungasensis d’Orbigny, 1837. The type status of the following taxa is changed to lectotype in accordance with Art. 74.6 ICZN: Bulimulus (Drymaeus) caucaensis da Costa, 1898; Drymaeus exoticus da Costa, 1901; Bulimulus (Drymaeus) hidalgoi da Costa, 1898; Bulimulus (Drymaeus) interruptus Preston, 1909; Bulimulus (Drymaeus) inusitatus Fulton, 1900; Bulimulus latecolumellaris Preston, 1909; Bulimus (Otostomus) napo Angas, 1878; Drymaeus notabilis da Costa, 1906; Drymaeus notatus da Costa, 1906; Bulimulus (Drymaeus) nubilus Preston, 1903; Drymaeus obliquistriatus da Costa, 1901; Bulimus (Drymaeus) ochrocheilus E.A. Smith, 1877; Bulimus (Drymaeus) orthostoma E.A. Smith, 1877; Drymaeus expansus perenensis da Costa, 1901; Bulimulus pergracilis Rolle, 1904; Bulimulus (Drymaeus) plicatoliratus da Costa, 1898; Drymaeus prestoni da Costa, 1906; Drymaeus punctatus da Costa, 1907; Bulimus (Leptomerus) sanctaeluciae E.A. Smith, 1889; Bulimulus (Drymaeus) selli Preston, 1909; Drymaeus subventricosus da Costa, 1901; Bulimulus (Drymaeus) tigrinus da Costa, 1898; Drymaeus volsus Fulton, 1907; Drymaeus wintlei Finch, 1929; Bulimus zhorquinensis Angas, 1879; Bulimulus (Drymaeus) ziczac da Costa, 1898. The following junior subjective synonyms are established: Bulimus antioquensis Pfeiffer, 1855 = Bulimus baranguillanus Pfeiffer, 1853; Drymaeus bellus da Costa, 1906 = Drymaeus blandi Pilsbry, 1897; Bulimus hachensis Reeve 1850 = Bulimus gruneri Pfeiffer, 1846 = Bulimus columbianus Lea, 1838; Bulimus (Otostomus) lamas Higgins 1868 = Bulimus trujillensis Philippi, 1867; Bulimulus (Drymaeus) binominis lascellianus E.A. Smith, 1895 = Bulimulus (Drymaeus) binominis E.A. Smith, 1895; Drymaeus multispira da Costa, 1904 = Helix torallyi d’Orbigny, 1835; Bulimulus (Drymaeus) plicatoliratus Da Costa, 1898 = Bulimus convexus Pfeiffer, 1855; Bulimus sugillatus Pfeiffer, 1857 = Bulimus rivasii d’Orbigny, 1837; Bulimus meridionalis Reeve 1848 [June] = Bulimus voithianus Pfeiffer, 1847. New combinations are: Bostryx montagnei (d’Orbigny, 1837); Bostryx obliquiportus (da Costa, 1901); Bulimulus heloicus (d’Orbigny, 1835); Drymaeus (Drymaeus) lusorius (Pfeiffer, 1855); Drymaeus (Drymaeus) trigonostomus (Jonas, 1844); Drymaeus (Drymaeus) wintlei Finch, 1929; Drymaeus (Mesembrinus) conicus da Costa, 1907; Kuschelenia (Kuschelenia) culminea culminea (d’Orbigny, 1835); Kusche

  20. Antimicrobial activities of the tissue extracts of Babylonia spirata Linnaeus, 1758 (Mollusca: Gastropoda) from Thazhanguda, southeast coast of India

    PubMed Central

    Periyasamy, N; Srinivasan, M; Balakrishnan, S

    2012-01-01

    Objective To investigate the antimicrobial activity of the tissue extracts of Babylonia spirata (B. spirata) against nine bacterial and three fungal pathogens. Methods Crude extract of gastropod was tested for inhibition of bacterial and fungal growth. Antibacterial assay was carried out by disc diffusion method and in vitro antifungal activity was determined against Czapex Dox agar. The antimicrobial activity was measured accordingly based on the inhibition zone around the disc impregnated with gastropod extract. Molecular size of muscle protein was determined using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). And fourier transform infrared spectroscopy (FTIR) spectro photometry analysis was also studied. Results The maximum inhibition zone (12 mm) was observed against Pseudomonas aeruginosa in the crude ethanol extract of B. spirata and the minimum inhibition zone (2 mm) was noticed against Staphylococcus aureus in the crude methanol extract of B. spirata. Water extract of B. spirata showed the highest activity against Vibrio parahaemolyticus, Staphylococcus aureus and Candida albicans. Ethanol, acetone, methanol, chloroform and water extracts showed antimicrobial activity against almost all the bacteria and fungus. Compared with water extracts, ethanol and methanol extracts showed higher activity against all pathogens. The molecular weight of protein of the gastropod sample ranged from 2-110 kDa on SDS-PAGE. FTIR analysis revealed the presence of bioactive compounds signals at different ranges. Conclusions The research shows that the great medicinal value of the gastropod muscle of B. spirata may be due to high quality of antimicrobial compounds. PMID:23569831

  1. Revision of Partulidae (Gastropoda, Stylommatophora) of Palau, with description of a new genus for an unusual ground-dwelling species.

    PubMed

    Slapcinsky, John; Kraus, Fred

    2016-01-01

    We describe a new stylommatophoran land snail of the family Partulidae from Palau. The new species has a combination of morphological and ecological characters that do not allow its placement in any existing partulid genus, so we describe a new genus for it. The new genus is characterized by a large (18-23 mm) obese-pupoid shell; smooth protoconch; teleoconch with weak and inconsistent, progressively stronger, striae; last half of body whorl not extending beyond the penultimate whorl; widely expanded and reflexed peristome; relatively long penis, with longitudinal pilasters that fuse apically into a fleshy ridge that divides the main chamber from a small apical chamber; and vas deferens entering and penial-retractor muscle attaching at the apex of the penis. Unlike all other partulids, the new species is strictly associated with rocks in contact with the ground. Comparing the other three Palauan species - currently assigned to Partula - to our new genus and to other partulids makes it clear that they require their own genus because their morphology is quite different from that of true Partula and from that of all other genera. Hence, we resurrect the name Palaopartula Pilsbry for these snails.

  2. The nudibranch names mentioned as n.sp. in Bergh (1861) are almost all nomina nuda (Gastropoda: Heterobranchia: Nudibranchia).

    PubMed

    Jensen, Kathe; Nielsen, Claus

    2014-01-01

    In a publication in Danish from 1861, Bergh described the nematocysts found in a number of nudibranch species. Many of the species had been described previously, but a number were new and given names, but without a description. These species are nomina nuda. We have translated the "descriptions", including the foot-notes, and reproduced the original plate to show that only the nematocysts (real or assumed) were described. The only species given a short description fulfilling the requirements of the ICZN is Pleurophyllidia quadrilateralis, which was described as the only species in the new genus Sancara. This in turn was shown to be a junior synonym of Linguella de Blainville, 1823. All the species were subsequently described anatomically in detail and made valid in a number of papers, and most of the type material is located in the Zoological Museum, Copenhagen (Natural History Museum of Denmark). The names in current use have been given. PMID:24872286

  3. Analysis of nitric oxide-cyclic guanosine monophosphate signaling during metamorphosis of the nudibranch Phestilla sibogae Bergh (Gastropoda: Opisthobranchia).

    PubMed

    Bishop, Cory D; Pires, Anthony; Norby, Shong-Wan; Boudko, Dmitri; Moroz, Leonid L; Hadfield, Michael G

    2008-01-01

    The gas nitric oxide (NO), and in some cases its downstream second messenger, cyclic guanosine monophosphate (cGMP) function in different taxa to regulate the timing of life-history transitions. Increased taxonomic sampling is required to foster conclusions about the evolution and function of NO/cGMP signaling during life-history transitions. We report on the function and localization of NO and cGMP signaling during metamorphosis of the nudibranch Phestilla sibogae. Pharmacological manipulation of NO or cGMP production in larvae modulated responses to a natural settlement cue from the coral Porites compressa in a manner that suggest inhibitory function for NO/cGMP signaling. However, these treatments were not sufficient to induce metamorphosis in the absence of cue, a result unique to this animal. We show that induction of metamorphosis in response to the settlement cue is associated with a reduction in NO production. We documented the expression of putative NO synthase (NOS) and the production of cGMP during larval development and observed no larval cells in which NOS and cGMP were both detected. The production of cGMP in a bilaterally symmetrical group of cells fated to occupy the distal tip of rhinophores is correlated with competence to respond to the coral settlement cue. These results suggest that endogenous NO and cGMP are involved in modulating responses of P. sibogae to a natural settlement cue. We discuss these results with respect to habitat selection and larval ecology. PMID:18460091

  4. Molecular and morphological systematics of Doto Oken, 1851 (Gastropoda: Heterobranchia), with descriptions of five new species and a new genus.

    PubMed

    Shipman, Carissa; Gosliner, Terrence

    2015-01-01

    The nudibranch family Dotidae has been an extremely challenging group to study taxonomically due to their small body size, lack of distinct internal morphological differences and similar color patterns. This integrative systematic study of the Dotidae encompasses 29 individuals from the north Atlantic and Mediterranean, and 11 from the Indo-Pacific. Two mitochondrial genes, 16S, COI, and a nuclear gene, H3, were sequenced for 31 specimens and Bayesian and RAxML concatenated analyses were run. Dotidae is monophyletic and possesses strong geographic structure. Co-evolution between some of the north Atlantic taxa and their hydroid prey is apparent, thus supporting the hypothesis that speciation may be correlated with prey diversification. This study also supports the notion that the hydroid prey is a reliable indicator for distinguishing between cryptic species. Doto coronata Gmelin, the type species for the genus Doto, is re-described and a neotype, collected near Goes, Netherlands, is designated. From the molecular data, D. millbayana, D. dunnei, D. koenneckeri, D. maculata Lemche within the Doto coronata species complex, are confirmed to be distinct from D. coronata. Based on molecular data, specimens previously identified as D. coronata from South Africa are determined to represent a new species. It is described here and named Doto africoronata n. sp. Kabeiro n. gen. is introduced for the clade of elongate individuals from the Indo-Pacific, which diverges by 11.6% or greater in 16S from short-bodied Doto species. These elongate species are sister to all the short-bodied species and possess an enlarged pericardium, elongate cerata, a reproductive system with a pocketed prostate (penial gland), and an external tube-like digestive gland, which are absent in short-bodied Doto. Species of Kabeiro described here are: Kabeiro christianae n. sp., Kabeiro rubroreticulata n. sp., and Kabeiro phasmida n. sp. from the Philippines. The Indo-Pacific short-bodied species, Doto greenamyeri n. sp. from Papua New Guinea is also described. PMID:26249713

  5. Mitochondrial DNA phylogeography of Semisulcospira libertina (Gastropoda: Cerithioidea: Pleuroceridae): implications the history of landform changes in Taiwan.

    PubMed

    Hsu, Kui-Ching; Bor, Hor; Lin, Hung-Du; Kuo, Po-Hsun; Tan, Mian-Shin; Chiu, Yuh-Wen

    2014-06-01

    The mitochondrial DNA cytochrome c oxidase subunit I sequences from 95 specimens of Semisulcospira libertina in Taiwan were identified as two major phylogroups, exhibiting a southern and northern distribution, north of Formosa Bank and south of Miaoli Plateau. The genetic distance between these two phylogroups was 12.20%, and the distances within-phylogroups were 4.97 and 5.56%. According to a molecular clock of 1.56% per lineage per million years, the divergence time between these two major phylogroups was estimated at 4.94 million years ago (mya), with the two phylogroups forming at 3.64 and 3.75 mya, respectively. Moreover, the geological events have suggested that Taiwan Island emerged above sea level at 4-5 mya, and became its present shape at 2 mya. These results suggested that these two phylogroups might originate from two independent ancestral populations or divergent before colonizing Taiwan. Within South phylogroup, the initial colonization was hypothesized to be in Kaoping River (WT), followed by its northward. The high divergence between south- and north of WT River was influenced by the formation of the Kaoping foreland basins. Within North phylogroup, the colonization was from central sub-region through paleo-Miaoli Plateau to northern and northeastern sub-regions. This study showed that the landform changes might have shaped the genetic structure of S. libertina in concert. Apparently, two cryptic species or five different genetic stocks of S. libertina could be identified; these results are useful for the evaluation and conservation of S. libertina in Taiwan.

  6. Parasitic castration of Buccinanops cochlidium (Gastropoda: Nassariidae) caused by a lepocreadiid digenean in San José Gulf, Argentina.

    PubMed

    Averbuj, A; Cremonte, F

    2010-12-01

    Parasitic castration of Buccinanops cochlidium from San José Gulf, Argentina, caused by a lepocreadiid digenean, is reported for the first time. Rediae and ophtalmotrichocercous cercariae probably belonging to Opechona sp. were identified in the gonad and digestive gland. Opechona sp. has been reported previously parasitizing B. monilifer from a northern locality in the Argentine Sea. Overall prevalence of infection was 15.5%; it varied seasonally, rising during the warm months after the host oviposition period. Cercariae were expelled at the same time as the hatching of snail embryos (during the higher water temperature period). Rediae affected male and female snails equally, but prevalence increases along with host size. The parasite causes the complete castration of the host. Parasitized adult snails showed a reduction of penis size in comparison with healthy males. It remains to be confirmed whether the peak of cercariae emission coincides with the presence of jellyfishes and scombrid or other fishes in the area, which could act as second intermediate and definitive hosts, respectively.

  7. Analysis of nitric oxide-cyclic guanosine monophosphate signaling during metamorphosis of the nudibranch Phestilla sibogae Bergh (Gastropoda: Opisthobranchia)

    PubMed Central

    Bishop, Cory D.; Pires, Anthony; Norby, Shong-Wan; Boudko, Dmitri; Moroz, Leonid L.; Hadfield, Michael G.

    2014-01-01

    SUMMARY The gas nitric oxide (NO), and in some cases its downstream second messenger, cyclic guanosine monophosphate (cGMP) function in different taxa to regulate the timing of life-history transitions. Increased taxonomic sampling is required to foster conclusions about the evolution and function of NO/cGMP signaling during life-history transitions. We report on the function and localization of NO and cGMP signaling during metamorphosis of the nudibranch Phestilla sibogae. Pharmacological manipulation of NO or cGMP production in larvae modulated responses to a natural settlement cue from the coral Porites compressa in a manner that suggest inhibitory function for NO/cGMP signaling. However, these treatments were not sufficient to induce metamorphosis in the absence of cue, a result unique to this animal. We show that induction of metamorphosis in response to the settlement cue is associated with a reduction in NO production. We documented the expression of putative NO synthase (NOS) and the production of cGMP during larval development and observed no larval cells in which NOS and cGMP were both detected. The production of cGMP in a bilaterally symmetrical group of cells fated to occupy the distal tip of rhinophores is correlated with competence to respond to the coral settlement cue. These results suggest that endogenous NO and cGMP are involved in modulating responses of P. sibogae to a natural settlement cue. We discuss these results with respect to habitat selection and larval ecology. PMID:18460091

  8. Opisthobranchs from the western Indian Ocean, with descriptions of two new species and ten new records (Mollusca, Gastropoda)

    PubMed Central

    Yonow, Nathalie

    2012-01-01

    Abstract Seventy species of opisthobranchs are described in this work based on collections from the Persian Gulf, Socotra, Kenya, Zanzibar, Madagascar, La Réunion, Mauritius, the Seychelles, the Maldives, and Sri Lanka. Ten species are newly recorded from the western Indian Ocean and four species are recorded in the scientific literature for the first time since their original descriptions. Two species are described as new: Cyerce bourbonica sp. n. from La Réunion and Doriopsilla nigrocerasp. n. from the Persian Gulf coast of Saudi Arabia. Chromodoris cavae is removed from its synonymy with Chromodoris tennentana and redescribed from specimens from La Réunion, while several new synonyms are proposed for some commonly occurring species. Risbecia bullockii is recorded for the second time from the Indian Ocean and assigned to its correct genus. PMID:22711992

  9. Description of two new Jujubinus species (Gastropoda: Trochidae) from the Sicily Channel, with notes on the Jujubinus curinii species complex.

    PubMed

    Smriglio, Carlo; Di Giulio, Andrea; Mariottini, Paolo

    2014-01-01

    Based on shell characters, two new species of the gastropod family Trochidae, Jujubinus eleonorae n. sp. and Jujubinus trilloi n. sp., from the Sicily Channel are described. Shells of the new taxa were collected in the lower infralittoral of the Skerki and Talbot Banks, respectively. The new taxa are compared with Jujubinus curinii Bogi & Campani, 2005, morphologically the most closely related species.

  10. A Good Compromise: Rapid and Robust Species Proxies for Inventorying Biodiversity Hotspots Using the Terebridae (Gastropoda: Conoidea)

    PubMed Central

    Modica, Maria Vittoria; Puillandre, Nicolas; Castelin, Magalie; Zhang, Yu; Holford, Mandë

    2014-01-01

    Devising a reproducible approach for species delimitation of hyperdiverse groups is an ongoing challenge in evolutionary biology. Speciation processes combine modes of passive and adaptive trait divergence requiring an integrative taxonomy approach to accurately generate robust species hypotheses. However, in light of the rapid decline of diversity on Earth, complete integrative approaches may not be practical in certain species-rich environments. As an alternative, we applied a two-step strategy combining ABGD (Automated Barcode Gap Discovery) and Klee diagrams, to balance speed and accuracy in producing primary species hypotheses (PSHs). Specifically, an ABGD/Klee approach was used for species delimitation in the Terebridae, a neurotoxin-producing marine snail family included in the Conoidea. Delimitation of species boundaries is problematic in the Conoidea, as traditional taxonomic approaches are hampered by the high levels of variation, convergence and morphological plasticity of shell characters. We used ABGD to analyze gaps in the distribution of pairwise distances of 454 COI sequences attributed to 87 morphospecies and obtained 98 to 125 Primary Species Hypotheses (PSHs). The PSH partitions were subsequently visualized as a Klee diagram color map, allowing easy detection of the incongruences that were further evaluated individually with two other species delimitation models, General Mixed Yule Coalescent (GMYC) and Poisson Tree Processes (PTP). GMYC and PTP results confirmed the presence of 17 putative cryptic terebrid species in our dataset. The consensus of GMYC, PTP, and ABGD/Klee findings suggest the combination of ABGD and Klee diagrams is an effective approach for rapidly proposing primary species proxies in hyperdiverse groups and a reliable first step for macroscopic biodiversity assessment. PMID:25003611

  11. Three-dimensional reconstruction of the odontophoral cartilages of Caenogastropoda (Mollusca: Gastropoda) using micro-CT: Morphology and phylogenetic significance.

    PubMed

    Golding, Rosemary E; Ponder, Winston F; Byrne, Maria

    2009-05-01

    Odontophoral cartilages are located in the molluscan buccal mass and support the movement of the radula during feeding. The structural diversity of odontophoral cartilages is currently known only from limited taxa, but this information is important for interpreting phylogeny and for understanding the biomechanical operation of the buccal mass. Caenogastropods exhibit a wide variety of feeding strategies, but there is little comparative information on cartilage morphology within this group. The morphology of caenogastropod odontophoral cartilages is currently known only from dissection and histology, although preliminary results suggest that they may be structurally diverse. A comparative morphological survey of 18 caenogastropods and three noncaenogastropods has been conducted, sampling most major caenogastropod superfamilies. Three-dimensional models of the odontophoral cartilages were generated using X-ray microscopy (micro-CT) and reconstruction by image segmentation. Considerable morphological diversity of the odontophoral cartilages was found within Caenogastropoda, including the presence of thin cartilaginous appendages, asymmetrically overlapping cartilages, and reflexed cartilage margins. Many basal caenogastropod taxa possess previously unidentified cartilaginous support structures below the radula (subradular cartilages), which may be homologous to the dorsal cartilages of other gastropods. As subradular cartilages were absent in carnivorous caenogastropods, adaptation to trophic specialization is likely. However, incongruence with specific feeding strategies or body size suggests that the morphology of odontophoral cartilages is constrained by phylogeny, representing a new source of morphological characters to improve the phylogenetic resolution of this group.

  12. The Pleistocene glaciations and the evolutionary history of the polytypic snail species Arianta arbustorum (Gastropoda, Pulmonata, Helicidae).

    PubMed

    Gittenberger, E; Piel, W H; Groenenberg, D S J

    2004-01-01

    The evolutionary history of the snail Arianta arbustorum is controversial. This diverse, polytypic species has two distinct forms: one, with a globular shell and closed umbilicus, is found from lowland to high altitudes; the other, with a depressed shell and open umbilicus, is found at a few scattered, high altitude localities. What is the origin of these two forms? Some believe that the depressed shell is a recent, local, ecotypic adaptation to alpine environments. Others believe that this form is a relic of an ancestral condition that may have survived the Pleistocene glaciations on nunatak-like montane refugia, while the globular shell is a derived condition and its presence at high altitudes follows post-Pleistocene recolonisation. We analysed a portion of the mitochondrial gene cytochrome oxidase I for 100 snails of the species A. arbustorum, three additional Arianta species, and nine outgroup taxa from five genera, in order to understand the phylogeographic history of the species. Despite some confounding artefacts that are likely due to introgression among the morphological forms, the resulting phylogeny shows that the depressed shell is plesiomorphic, while the globular shell is derived. Moreover, their disparate histories suggest that the depressed shell variety survived the glaciations in pockets of alpine refugia, while the globular shell variety recolonised the alpine environment post-glacially. PMID:15022758

  13. Analysis of a deep transcriptome from the mantle tissue of Patella vulgata Linnaeus (Mollusca: Gastropoda: Patellidae) reveals candidate biomineralising genes.

    PubMed

    Werner, Gijsbert D A; Gemmell, Patrick; Grosser, Stefanie; Hamer, Rebecca; Shimeld, Sebastian M

    2013-04-01

    The gastropod Patella vulgata is abundant on rocky shores in Northern Europe and a significant grazer of intertidal algae. Here we report the application of Illumina sequencing to develop a transcriptome from the adult mantle tissue of P. vulgata. We obtained 47,237,104 paired-end reads of 51 bp, trialled de novo assembly methods and settled on the additive multiple K method followed by redundancy removal as resulting in the most comprehensive assembly. This yielded 29,489 contigs of at least 500 bp in length. We then used three methods to search for candidate genes relevant to biomineralisation: searches via BLAST and Hidden Markov Models for homologues of biomineralising genes from other molluscs, searches for predicted proteins containing tandem repeats and searches for secreted proteins that lacked a transmembrane domain. From the results of these searches we selected 15 contigs for verification by RT-PCR, of which 14 were successfully amplified and cloned. These included homologues of Pif-177/BSMP, Perlustrin, SPARC, AP24, Follistatin-like and Carbonic anhydrase, as well as three containing extensive G-X-Y repeats as found in nacrein. We selected two for further verification by in situ hybridisation, demonstrating expression in the larval shell field. We conclude that de novo assembly of Illumina data offers a cheap and rapid route to a predicted transcriptome that can be used as a resource for further biological study. PMID:22865210

  14. Annotated type catalogue of the Bothriembryontidae and Odontostomidae (Mollusca, Gastropoda, Orthalicoidea) in the Natural History Museum, London

    PubMed Central

    Breure, Abraham S.H.; Ablett, Jonathan D.

    2012-01-01

    Abstract The type status is described for specimens of 84 taxa classified within the families Bothriembryontidae and Odontostomidae (superfamily Orthalicoidea) and kept in the Natural History Museum, London. Lectotypes are designated for Bulimus (Liparus) brazieri Angas, 1871; Bulimus broderipii Sowerby I, 1832; Bulimus fuligineus Pfeiffer, 1853; Helix guarani d’Orbigny, 1835; Bulimus (Tomigerus) ramagei E.A. Smith, 1890; Helix rhodinostoma d’Orbigny, 1835; Bulimus (Bulimulus) ridleyi E.A. Smith, 1890. The type status of the following taxa is changed to lectotype in accordance with Art. 74.6 ICZN: Placostylus (Euplacostylus) cylindricus Fulton, 1907; Bulimus pyrostomus Pfeiffer, 1860; Bulimus turneri Pfeiffer, 1860. The following taxon is synonymised: Bulimus oblitus Reeve, 1848 = Bahiensis neglectus (Pfeiffer, 1847). PMID:22539914

  15. The South American radiation of Jerrybuccinum (Gastropoda, Buccinidae), with a new deep-water species from Chile

    PubMed Central

    Fraussen, Koen; Sellanes, Javier; Stahlschmidt, Peter

    2014-01-01

    Abstract A new deep water species from off the Chilean coast, Jerrybuccinum kantori sp. n., is described. The animal is equipped with a large statocyst. Kryptos explorator Fraussen & Sellanes, 2008 from off Concepción is found to be congeneric and transferred to the genus Jerrybuccinum. Differences in size and sculpture serve to distinguish the new species from J. explorator. Both Chilean species are associated with methane seep or low oxygen environments. They are compared with J. malvinense Kantor & Pastorino, 2009 and two still unnamed species from the Falkland Plateau. PMID:24899844

  16. Philinidae, Laonidae and Philinorbidae (Gastropoda: Cephalaspidea: Philinoidea) from the northeastern Pacific Ocean and the Beaufort Sea (Arctic Ocean).

    PubMed

    Valdés, Ángel; Cadien, Donald B; Gosliner, Terrence M

    2016-01-01

    Based on morphological data a total of nine native species of Philinidae are recognized from the northeastern Pacific including the Bering Sea and the adjacent Arctic Ocean (Beaufort Sea). Four of them have been previously described: Philine ornatissima Yokoyama, 1927, Philine bakeri Dall, 1919, Philine polystrigma (Dall, 1908), and Philine hemphilli Dall, 1919. Five of them are new and described herein: Philine mcleani sp. nov., Philine baxteri sp. nov., Philine malaquiasi sp. nov., Philine wareni sp. nov., and Philine harrisae sp. nov. These species display a substantial degree of variation in internal and external morphological traits (i.e., presence/absence of gizzard plates, different radular structure and tooth morphology, various reproductive anatomical features) and it is likely that they belong to different clades (genera). However, in the absence of a comprehensive phylogeny for Philine, they are here provisionally regarded as Philine sensu lato. In addition to the nine native species, two introduced species: Philine orientalis A. Adams, 1854 and Philine auriformis Suter, 1909 are here illustrated and compared to the native species to facilitate identification. Finally, two species previously considered members of Philinidae are examined anatomically and confirmed as members of Laonidae, Laona californica (Willett, 1944) and Philinorbidae, Philinorbis albus (Mattox, 1958), based on morphological data. PMID:27515632

  17. Taxonomic review of the family Discodorididae (Mollusca: Gastropoda: Nudibranchia) from Brazil, with descriptions of two new species.

    PubMed

    Alvim, Juliana; Pimenta, Alexandre Dias

    2013-01-01

    The family Discodorididae was previously represented by 11 species in Brazil; however, recently collected specimens from several localities in Rio de Janeiro, in addition to the study of material previously deposited in scientific collections, revealed the existence of 13 taxa: Diaulula greeleyi (MacFarland, 1909), Discodoris hummelincki (Ev. Marcus & Er. Marcus, 1963) comb. nov., Discodoris branneri MacFarland, 1909, Geitodoris pusae (Er. Marcus, 1955), Hoplodoris hansrosaorum Domínguez, García & Troncoso, 2006, Jorunna spazzola Er. Marcus, 1955, Jorunna spongiosa sp. nov., Paradoris mulciber (Ev. Marcus, 1971), Platydoris angustipes (Mörch, 1863), Rostanga byga Er. Marcus, 1958a, Taringa telopia Er. Marcus, 1955, Taringa iemanja sp. nov., and Thordisa diuda Er. Marcus, 1955. Discodoris voniheringi MacFarland, 1909 was previously regarded as nomen dubium, and this view is maintained in the present study. Three new records for the Brazilian coast are recognized among these 13 taxa; the previous record of Diaulula phoca (Ev. Marcus & Er. Marcus, 1967a) is rectified as Discodoris hummelincki comb. nov., constituting the first record of this species from Brazil; two new species, Taringa iemanja sp. nov. and Jorunna spongiosa sp. nov., are described in anatomical detail. The following taxa, which were formerly considered junior synonyms of species studied in this work, have been revalidated: Diaulula nayarita (Ortea & Llera, 1981), from the Pacific coast of Costa Rica, which differs from Diaulula greeleyi in the length and width of caryophyllidia; Discodoris mortenseni Ev. Marcus & Er. Marcus, 1963, from the Caribbean, which is likely to belong to Jorunna, yet differs from Jorunna spazzola in body size and coloration, radula appearance, and number of lamellae in the rhinophores; Jorunna luisae Ev. Marcus, 1976, which differs from Jorunna spazzola in the reproductive system, mainly in the size and shape of the accessory gland; and Thordisa azmani Cervera & García-Gómez, 1989, which differs from Thordisa diuda in the presence of two accessory glands in the genital atrium and the absence of one denticle in the external surface of the inner lateral teeth. Finally, the specimens of Geitodoris pusae reported from the European coast and Mediterranean Sea show differences in general coloration and in the radula, gill, and reproductive system, thereby these specimens likely refer to different taxa.

  18. A question of time: the land snail Murella muralis (Gastropoda: Pulmonata) reveals constraints on past ecological speciation.

    PubMed

    Fiorentino, V; Manganelli, G; Giusti, F; Tiedemann, R; Ketmaier, V

    2013-01-01

    The lively debate about speciation currently focuses on the relative importance of factors driving population differentiation. While many studies are increasingly producing results on the importance of selection, little is known about the interaction between drift and selection. Moreover, there is still little knowledge on the spatial-temporal scales at which speciation occurs, that is, arrangement of habitat patches, abruptness of habitat transitions, climate and habitat changes interacting with selective forces. To investigate these questions, we quantified variation on a fine geographical scale analysing morphological (shell) and genetic data sets coupled with environmental data in the land snail Murella muralis, endemic to the Mediterranean island of Sicily. Analysis of a fragment of the mitochondrial DNA cytochrome oxidase I gene (COI) and eight nuclear microsatellite loci showed that genetic variation is highly structured at a very fine spatial scale by local palaeogeographical events and historical population dynamics. Molecular clock estimates, calibrated here specifically for Tyrrhenian land snails, provided a framework of palaeogeographical events responsible for the observed geographical variations and migration routes. Finally, we showed for the first time well-documented lines of evidence of selection in the past, which explains divergence of land snail shell shapes. We suggest that time and palaeogeographical history acted as constraints in the progress along the ecological speciation continuum. Our study shows that testing for correlation among palaeogeography, morphology and genetic data on a fine geographical scale provides information fundamental for a detailed understanding of ecological speciation processes.

  19. Recent expansion and relic survival: Phylogeography of the land snail genus Helix (Mollusca, Gastropoda) from south to north Europe.

    PubMed

    Fiorentino, V; Manganelli, G; Giusti, F; Ketmaier, V

    2016-05-01

    Little is known about the evolutionary history of Helix, despite the fact that it includes the largest land snails in the western Palaearctic, some of which (e.g. H. pomatia Linnaeus, 1758) are valuable human food. We compared two groups of Helix with apparently contrasting evolutionary histories: the widespread species H. pomatia and the group distributed along the Italian Apennine chain, a relatively unknown set of species with a restricted distribution over a range of altitudes. To reconstruct the evolutionary trajectories of these two groups, we analysed morphological (shell and genitalia) and molecular characters (mitochondrial and nuclear markers) in a total of 59 populations from northern and central Europe (H. pomatia) and along the Apennine chain (various species). We also reconstructed the phylogeny and the evolutionary history of the genus by combining our data with that currently available in the literature. We found that spatial changes did not merely imply fragmentation of populations, but also implied environmental changes (woodlands vs. grasslands) that may have triggered the observed phenotypic diversification. We also found that Anatolia is the ancestral range of Helix and is therefore an important area for the Palaearctic diversity. The results provide insights into the evolutionary history of species richness and more generally into the processes that may have shaped the distribution and diversification of these organisms across Europe and the peri-Mediterranean area.

  20. Annotated type catalogue of the Orthalicoidea (Mollusca, Gastropoda) in the Museum für Naturkunde, Berlin

    PubMed Central

    Breure, Abraham S.H.

    2013-01-01

    Abstract The type status is described of 96 taxa classified within the superfamily Orthalicoidea and present in the Mollusca collection of the Museum für Naturkunde der Humboldt-Universität zu Berlin. Lectotypes are designated for the following taxa: Orthalicus elegans Rolle, 1895; Bulimus maranhonensis Albers, 1854; Orthalicus nobilis Rolle, 1895; Orthalichus tricinctus Martens, 1893. Orthalicus sphinx tresmariae is introduced as new name for Zebra sphinx turrita Strebel, 1909, not Zebra quagga turrita Strebel, 1909. The following synonyms are established: Zebra crosseifischeri Strebel, 1909 = Orthalicus princeps fischeri Martens, 1893; Orthalicus isabellinus Martens, 1873 = Orthalicus bensoni (Reeve, 1849); Zebra zoniferus naesiotes Strebel, 1909 = Orthalicus undatus (Bruguière, 1789); Porphyrobaphe (Myiorthalicus) dennisoni pallida Strebel, 1909 = Hemibulimus dennisoni (Reeve, 1848); Zebra delphinus pumilio Strebel, 1909 = Orthalicus delphinus (Strebel, 1909); Orthalicus (Laeorthalicus) reginaeformis Strebel, 1909 = Corona perversa (Swainson, 1821); Bulimus (Eurytus) corticosus Sowerby III, 1895 = Plekocheilus (Eurytus) stuebeli Martens, 1885. The taxon Bulimus (Eudioptus) psidii Martens, 1877 is now placed within the family Sagdidae, tentatively in the genus Platysuccinea. Appendices are included with an index to all the types of Orthalicoidea extant (including those listed by Köhler 2007) and a partial list of letters present in the correspondence archives. PMID:23794831

  1. Bulinus globosus (Planorbidae; Gastropoda) populations in the Lake Victoria basin and coastal Kenya show extreme nuclear genetic differentiation.

    PubMed

    Nyakaana, Silvester; Stothard, J Russell; Nalugwa, Allen; Webster, Bonnie L; Lange, Charles N; Jørgensen, Aslak; Rollinson, David; Kristensen, Thomas K

    2013-11-01

    Bulinus globosus, a key intermediate host for Schistosoma haematobium that causes urinary schistosomiasis, is a hermaphroditic freshwater Planorbid snail species that inhabits patchy and transient water bodies prone to large seasonal variations in water availability. Although capable of self-fertilizing, this species has been reported to be preferentially out crossing. In this study, we characterized the population genetic structure of 19 B. globosus populations sampled across the Lake Victoria basin and coastal Kenya using four polymorphic microsatellite loci. Population genetic structure was characterized and quantified using FST statistics and Bayesian clustering algorithms. The four loci used in this study contained sufficient statistical power to detect low levels of population genetic differentiation and were highly polymorphic with the number of alleles per locus across populations ranging from 16 to 22. Average observed and expected heterozygosities across loci in each population ranged from 0.13 to 0.69 and from 0.39 to 0.79, respectively. Twenty-five of the seventy-six possible population-locus comparisons significantly deviated from Hardy-Weinberg equilibrium proportions after Bonferroni corrections, mostly due to the deficiency of heterozygotes. Significant genetic differentiation was observed between populations and Bayesian inferences identified 15 genetic clusters. The excess homozygosity, significant inbreeding and population genetic differentiation observed in B. globosus populations are likely to be due to the habitat patchiness, mating system and the proneness to cyclic extinction and recolonization in transient habitats. PMID:23266524

  2. Revision of the genus Turris Batsch, 1789 (Gastropoda: Conoidea: Turridae) with the description of six new species

    PubMed Central

    Kilburn, Richard N.; Fedosov, Alexander E.; Olivera, Baldomero M.

    2012-01-01

    The taxonomy of the genus Turris Batsch, 1789, type genus of the family Turridae, widespread in shallow-water habitats of tropic Indo-Pacific, is revised. A total of 31 species of Turris, are here recognized as valid. New species described: Turris chaldaea, Turris clausifossata, Turris guidopoppei, Turris intercancellata, Turris kantori, T. kathiewayae. Homonym renamed: Turris bipartita nom. nov. for Pleurotoma variegata Kiener, 1839 (non Philippi, 1836). New synonymies: Turris ankaramanyensis Bozzetti, 2006 = Turris tanyspira Kilburn, 1975; Turris imperfecti, T. nobilis, T. pulchra and T. tornatum Röding, 1798, and Turris assyria Olivera, Seronay & Fedosov, 2010 = T. babylonia; Turris dollyi Olivera, 2000 = Pleurotoma crispa Lamarck, 1816; Turris totiphyllis Olivera, 2000 = Turris hidalgoi Vera-Peláez, Vega-Luz & Lozano-Francisco, 2000; Turris kilburni Vera-Peláez, Vega-Luz & Lozano-Francisco, 2000 = Turris pagasa Olivera, 2000; Turris (Annulaturris) munizi Vera-Peláez, Vega-Luz & Lozano-Francisco, 2000 = Gemmula lululimi Olivera, 2000. Revised status: Turris intricata Powell, 1964, Pleurotoma variegata Kiener, 1839 (non Philippi, 1836) and Pleurotoma yeddoensis Jousseaume, 1883, are regarded as full species (not subspecies of Turris crispa). Neotype designated: For Pleurotoma garnonsii Reeve, 1843, to distinguish it from Turris garnonsii of recent authors, type locality emended to Zanzibar. New combination: Turris orthopleura Kilburn, 1983, is transferred to genus Makiyamaia, family Clavatulidae. PMID:23847408

  3. Host and ecology both play a role in shaping distribution of digenean parasites of New Zealand whelks (Gastropoda: Buccinidae: Cominella).

    PubMed

    Donald, Kirsten M; Spencer, Hamish G

    2016-08-01

    Digenean parasites infecting four Cominella whelk species (C. glandiformis, C. adspersa, C. maculosa and C. virgata), which inhabit New Zealand's intertidal zone, were analysed using molecular techniques. Mitochondrial 16S and cytochrome oxidase 1 (COI) and nuclear rDNA ITS1 sequences were used to infer phylogenetic relationships amongst digenea. Host species were parasitized by a diverse range of digenea (Platyhelminthes, Trematoda), representing seven families: Echinostomatidae, Opecoelidae, Microphallidae, Strigeidae and three, as yet, undetermined families A, B and C. Each parasite family infected between one and three host whelk species, and infection levels were typically low (average infection rates ranged from 1·4 to 3·6%). Host specificity ranged from highly species-specific amongst the echinostomes, which were only ever observed infecting C. glandiformis, to the more generalist opecoelids and strigeids, which were capable of infecting three out of four of the Cominella species analysed. Digeneans displayed a highly variable geographic range; for example, echinostomes had a large geographic range stretching the length of New Zealand, from Northland to Otago, whereas Family B parasites were restricted to fairly small areas of the North Island. Our results add to a growing body of research identifying wide ranges in both host specificity and geographic range amongst intertidal, multi-host parasite systems. PMID:27278710

  4. Replacement names and nomenclatural comments for problematic species-group names in Europe's Neogene freshwater Gastropoda. Part 2

    PubMed Central

    Neubauer, Thomas A.; Harzhauser, Mathias; Kroh, Andreas; Elisavet, Georgopoulou; Mandic, Oleg

    2014-01-01

    Abstract In the course of a new database project on Miocene to Recent freshwater gastropods of Europe, a great many of primary and secondary homonyms were revealed. Such nomenclatural issues need clarification in order to avoid misunderstandings and wrong statements about geographical distributions and temporal ranges. The following 16 new names are introduced to replace existing homonyms: Theodoxus militaris jurisicpolsakae nom. n., Viviparus stevanovici nom. n., Melanopsis haueri ripanjensis nom. n., Melanopsis wolfgangfischeri nom. n., Micromelania ramacanensis nom. n., Pseudamnicola welterschultesi nom. n., Muellerpalia haszprunari nom. n., Muellerpalia pseudovalvatoides nom. n., Lithoglyphus gozhiki nom. n., Valvata heidemariae willmanni nom. n., Radix macaleti nom. n., Gyraulus okrugljakensis nom. n., Gyraulus rasseri nom. n., Gyraulus vrapceanus nom. n., Planorbarius halavatsi nom. n., and Segmentina mosbachensis nom. n. Additionally, six cases of homonyms are discussed that are not replaced by new names, because they are considered junior synonyms. PMID:25147468

  5. Checklist of the family Epitoniidae (Mollusca: Gastropoda) in Taiwan with description of a new species and some new records

    PubMed Central

    Huang, Chih-Wei; Lee, Yen-Chen

    2016-01-01

    Abstract Background The family Epitoniidae is a group of small to medium-sized gastropods and occurs globally from the intertidal zone to abyssal seabeds. There are 101 epitoniid species currently recorded from Taiwan. New information Based on our investigations of seashores and fishing ports of Taiwan, a new species and 12 new records of Epitoniidae species are reported. Of the 12 new records, four are new to the East Asian region and two are new records to the Indo-Pacific region. Our results increase the number of Taiwanese Epitoniidae from 101 species to 114 species.

  6. Mitochondrial and nuclear DNA analysis revealed a cryptic species and genetic introgression in Littorina sitkana (Mollusca, Gastropoda).

    PubMed

    Azuma, Noriko; Yamazaki, Tomoyasu; Chiba, Susumu

    2011-12-01

    We investigated mitochondrial and nuclear DNA genotypes in nominal Littorina sitkana samples from 2 localities in Eastern Hokkaido, northern Japan. Our results indicated the existence of cryptic species. In the analysis of partial mitochondrial Cytchrome b gene sequences, haplotypes of L. sitkana samples were monophyletic in a phylogenetic tree with orthologous sequences from other Littorina species, but were apparently separated in 2 clades. One included typical L. sitkana (CBa clade) samples, which formed a clade with an allopatric species, L. horikawai. The other, CBb, was independent from CBa and L. horikawai. Haplotypes of the mitochondrial 16S rRNA gene also separated into 2 clades. We additionally examined intron sequence of the heat shock cognate 70 (HSC70) nuclear gene and identified 17 haplotypes. These were also separated into 2 clades, HSCa and HSCb. Among the examined Hokkaido samples, 60% of individuals were heterozygotes. However, each heterozygote consisted of haplotypes from the same clade, HSCa or HSCb, and no admixture of HSCa and HSCb haplotypes was observed. These results indicate reproductive isolation between the 2 clades. Among the genotyped Hokkaido samples, 93% of individuals had CBa + HSCa or CBb + HSCb genotypes, and 7% had CBb + HSCa genotypes. The discrepancy between the mtDNA and nuclear DNA haplotypes in a few individuals may have been caused by genetic introgression due to past hybridization. PMID:22374127

  7. Heat production in Littorina saxatilis Olivi and Littorina neritoides L. (gastropoda: Prosobranchia) during an experimental exposure to air

    NASA Astrophysics Data System (ADS)

    Kronberg, Inge

    1990-06-01

    The adaptation of littorinid molluscs to prolonged aerial exposure was investigated by the determination of heat production. Littorina saxatilis, inhabiting the upper eulittoral, reached a maximum metabolic activity during submersion (heat production: 3.26×10-3J s-1 (gadw)-1. On the first three days of desiccation, the heat production was continuously reduced to 40% of the submersed value. A prolonged aerial exposure was lethal for this species. In the supralittoral L. neritoides, three stages of energy metabolism could be observed: An intermediate heat production during submersion (1.97×10-3Js-1 (gadw)-1), an increased metabolism during the first hour of aerial exposure (heat production 204% of submersed value), and a minimal metabolism (39% of the submersed value and 19% of maximum value) during the following days and weeks of desiccation. Recovery depended on water salinity; L. saxatilis proved to be less euryhaline than L. neritoides. Thus, the metabolic adaptations correlate with the level of littoral habitat; inactivity combined with a drastically reduced energy consumption is a metabolically economic way to survive in periodically dry environments.

  8. No Evidence for a Culturable Bacterial Tetrodotoxin Producer in Pleurobranchaea maculata (Gastropoda: Pleurobranchidae) and Stylochoplana sp. (Platyhelminthes: Polycladida)

    PubMed Central

    Salvitti, Lauren R.; Wood, Susanna A.; McNabb, Paul; Cary, Stephen Craig

    2015-01-01

    Tetrodotoxin (TTX) is a potent neurotoxin found in the tissues of many taxonomically diverse organisms. Its origin has been the topic of much debate, with suggestions including endogenous production, acquisition through diet, and symbiotic bacterial synthesis. Bacterial production of TTX has been reported in isolates from marine biota, but at lower than expected concentrations. In this study, 102 strains were isolated from Pleurobranchaea maculata (Opisthobranchia) and Stylochoplana sp. (Platyhelminthes). Tetrodotoxin production was tested utilizing a recently developed sensitive method to detect the C9 base of TTX via liquid chromatography—mass spectrometry. Bacterial strains were characterized by sequencing a region of the 16S ribosomal RNA gene. To account for the possibility that TTX is produced by a consortium of bacteria, a series of experiments using marine broth spiked with various P. maculata tissues were undertaken. Sixteen unique strains from P. maculata and one from Stylochoplana sp. were isolated, representing eight different genera; Pseudomonadales, Actinomycetales, Oceanospirillales, Thiotrichales, Rhodobacterales, Sphingomonadales, Bacillales, and Vibrionales. Molecular fingerprinting of bacterial communities from broth experiments showed little change over the first four days. No C9 base or TTX was detected in isolates or broth experiments (past day 0), suggesting a culturable microbial source of TTX in P. maculata and Stylochoplana sp. is unlikely. PMID:25635464

  9. Global phylogeny and new classification of the Rapaninae (Gastropoda: Muricidae), dominant molluscan predators on tropical rocky seashores.

    PubMed

    Claremont, Martine; Vermeij, Geerat J; Williams, Suzanne T; Reid, David G

    2013-01-01

    The monophyly of the muricid subfamily Rapaninae has recently been confirmed with molecular techniques, but its composition and the relationships among its constituent genera remain unclear. We use four genes (28S rRNA, 12S rRNA, 16S rRNA and cytochrome c oxidase subunit I, COI) to construct a Bayesian phylogeny of 80 rapanine species (73% of the approximately 109 currently accepted), representing 27 of the 31 nominal genera. This is the most complete phylogeny of this taxonomically confusing subfamily yet produced. We propose a revised phylogenetic classification of the Rapaninae, assigning the recognized species to 28 genera. Most of the morphologically-defined rapanine genera are considered valid, including Purpura, Drupa, Thais and Nassa, but many of them are here restricted or redefined so that they are monophyletic. In particular the familiar genus Thais is narrowly restricted to a single species. Many groups previously accepted as subgenera, including Mancinella, Vasula, Thalessa and Thaisella, are here accorded full generic rank. We describe one new genus, Indothais. While we do not formally alter species-level taxonomy, we show molecular evidence for two cryptic species and several instances of probable species synonymy. We estimate the age of diversification of the Rapaninae as Late Cretaceous (75.9 Ma) and of many of its genera as Miocene. PMID:23026810

  10. Subgeneric division of the genus Orcula Held 1837 with remarks on Romanian orculid data (Gastropoda, Pulmonata, Orculidae)

    PubMed Central

    Páll-Gergely, Barna; Deli, Tamás; Irikov, Atanas; Harl, Josef

    2013-01-01

    Abstract The genital anatomy of Orcula jetschini (Romania), Orcula zilchi (Bulgaria), and Orcula wagneri (Albania) is described. Based on anatomical features (morphology of the penial caecum) shell characters (sculpture and shape) and unpublished molecular data the genus Orcula is subdivided into three subgenera. Orcula zilchi was classified within the monotypic subgenus Orcula (Hausdorfia) subgen. n.; Orcula jetschini, Orcula wagneri, and Orcula schmidtii were classified to Orcula (Illyriobanatica) subgen. n. (type species: Pupa schmidtii) whereas the other Orcula species remain in the nominotypical subgenus. Orcula (Hausdorfia) is known from South-Eastern Bulgaria and North-Western Turkey, Orcula (Illyriobanatica) inhabits Western Romania, North-Western Greece, Albania, Macedonia, Kosovo, and Montenegro. The nine species of Orcula (Orcula) are known mainly from the Alps and the Western Carpathians (from Eastern France to Eastern Hungary and Slovakia). The occurrence of only one Orcula species namely Orcula jetschini is verified from Romania. Available information suggests that data on the Romanian occurrence of Orcula dolium and Orcula gularis were based on wrongly identified specimens. Sphyradium dobrogicum (=Orcula dobrogica) is considered as a synonym of Sphyradium doliolum. PMID:23794893

  11. First record of the invasive snail Melanoides tuberculatus (Gastropoda: Prosobranchia: Thiaridae) in the Paranã River Basin, GO, Brazil.

    PubMed

    Rocha-Miranda, F; Martins-Silva, M J

    2006-11-01

    The Thiarid snail Melanoides tuberculatus (Müller, 1774), native to Asia and East Africa was recorded for the first time in the Paranã River basin, Goiás State. There is no evidence concerning introduction vectors but aquarium releases is the most probable vector. Specimens were collected at three different water bodies after twenty-seven rivers were investigated. The possible spread of this species to other habitats and potential effects on native thermal water communities are discussed.

  12. Pseudosuccinea columella (Say 1817) (Gastropoda, Lymnaeidae), snail host of Fasciola hepatica: first record for France in the wild.

    PubMed

    Pointier, Jean-Pierre; Coustau, Christine; Rondelaud, Daniel; Theron, André

    2007-10-01

    The lymnaeid snail Pseudosuccinea columella has shown strong invasive capabilities in the last decades, and this species has now a worldwide distribution. So far, the presence of this snail in Europe was restricted to botanical gardens, but the recent discovery of a few specimens along the banks of the Lot River, southwestern France is the first record of this species in the wild. The first generation of this P. columella isolate obtained in the laboratory was used for parasitological tests with a French Fasciola hepatica sample. Experimental infections showed that 100% of snails (n=26) developed infection when exposed to F. hepatica miracidia. Consequences for the epidemiology of F. hepatica transmission in France are discussed.

  13. Evaluation of radiography, ultrasonography and endoscopy for detection of shell lesions in live abalone Haliotis iris (Mollusca: Gastropoda).

    PubMed

    Nollens, Hendrik H; Schofield, John C; Keogh, Jonathan A; Probert, P Keith

    2002-07-01

    Radiography, ultrasonography and endoscopy were examined for their efficacy as non-destructive techniques for the detection of shell lesions in the marine gastropod Haliotis iris Gmelin. X-rays provided 69% correct diagnoses, with detection being restricted to those lesions which were mineralised. Ultrasound also showed potential to reliably detect lesions (83% correct diagnoses), but only where the lesions demonstrated a clear 3-dimensional relief. Lesion dimensions were underestimated using ultrasound. Endoscopy, applied to anaesthetised individuals, provided the most accurate method (92% correct diagnoses) for lesion detection and, although invasive, had no discernible effect on survival of the abalone 8 mo after screening.

  14. Do the changes in temperature and light affect the functional response of the benthic mud snail Heleobia australis (Mollusca: Gastropoda)?

    PubMed

    Magalhães, Thaisa R F; Neves, Raquel A F; Valentin, Jean L; Figueiredo, Gisela M

    2014-09-01

    The aim of this study was to determine the influence of temperature increase combined to conditions of light incidence on functional response of Heleobia australis. Experiments were conducted using nine to ten food concentrations for each treatment: 20°C without light; 30°C without light and, 30°C under low light intensity. For each experiment, the functional response type III (sigmoidal) was fitted and equation parameters were determined. Results suggest that, if the sediment temperature increases, H. australis will not have its ingestion rates affected negatively, whilst its feeding behavior seems to be negatively affected by light. Ingestion rates estimated for organic content in the Guanabara Bay were: 0.34 µgC ind-1h-1 at 20°C without light, 1.44 µgC ind-1h-1 at 30°C without light and 0.64 µgC ind-1h-1 at 30°C under light incidence. Higher ingestion rates were estimated at the high temperature, even under light incidence, and temperature seems to have outweighed the light effect. In contrast, if higher carbon content is considered, despite high temperature, the experiment conducted with light incidence showed lower ingestion rates than those from the experiment at 20°C without light. This study provides the first quantification of H. australis ingestion rates and the effects that changes in temperature and light have on its feeding behavior.

  15. Exploring Species Level Taxonomy and Species Delimitation Methods in the Facultatively Self-Fertilizing Land Snail Genus Rumina (Gastropoda: Pulmonata)

    PubMed Central

    Prévot, Vanya; Jordaens, Kurt; Sonet, Gontran; Backeljau, Thierry

    2013-01-01

    Delimiting species in facultatively selfing taxa is a challenging problem of which the terrestrial pulmonate snail genus Rumina is a good example. These snails have a mixed breeding system and show a high degree of shell and color variation. Three nominal species (R. decollata, R. saharica and R. paivae) and two color morphs within R. decollata (dark and light) are currently recognized. The present study aims at evaluating to what extent these entities reflect evolutionary diverging taxonomic units, rather than fixed polymorphisms due to sustained selfing. Therefore, a phylogenetic analysis of nuclear (ITS1, ITS2) and mitochondrial DNA (COI, CytB, 12S rDNA, 16S rDNA) sequences was performed. Putative species in Rumina, inferred from the mitochondrial DNA phylogeny, were compared with those proposed on the basis of the COI gene by (1) DNA barcoding gap analysis, (2) Automatic Barcode Gap Discovery, (3) the species delimitation plug-in of the Geneious software, (4) the Genealogical Sorting Index, and (5) the General Mixed Yule Coalescent model. It is shown that these methods produce a variety of different species hypotheses and as such one may wonder to what extent species delimitation methods are really useful. With respect to Rumina, the data suggest at least seven species, one corresponding to R. saharica and six that are currently grouped under the name R. decollata. The species-level status of R. paivae is rejected. PMID:23577154

  16. Impacts of Urbanization on the Biodiversity of the Imperiled Snail Fauna (Gastropoda: Prosobranchia: Pleuroceridae) of the Cahaba River, Alabama, USA.

    NASA Astrophysics Data System (ADS)

    Tolley-Jordan, L.; Huryn, A.

    2005-05-01

    The conservation of the Pleuroceridae is of concern in the Mobile River Basin (MRB) since 31 of 38 extinct gastropod species from this drainage are pleurocerids. The fauna of the Cahaba River, as a global hot-spot for pleurocerid diversity, is of particular concern. Its flow is not regulated by dams, so its fauna has not been affected by habitat alteration due to impoundment like other major MRB tributaries. Ongoing urbanization within its watershed, however, is expected to have consequences for its snail fauna. A 1993 survey documented 23 pleurocerid species among 109 sites in the drainage. Changes in land cover from 1992 to 2004 were quantified for 10 of these. Five sites showed a 13-36% increase in urban land-cover; five showed no change. Elimia cahawbensis, E. carinifera, E. carinocostata, E. clara and Pleurocera vestita occurred among these sites during 1993 (S= 0-4 spp./site). A comparison of species occurrence in 1992 and 2005 showed no change in S at 6 sites, while three lost 1 species, and one lost 3 species. Reductions in S were not correlated with changes in land cover, however. Factors not directly correlated with urbanization may thus be contributing to losses of snail diversity in the MRB.

  17. Heavy metal levels in Nucella lapillus (gastropoda: prosobranchia) from sites with normal and penis-bearing females from New England

    SciTech Connect

    Miller, E.R. III; Pondick, J.S.

    1984-11-01

    Pseudohermaphroditism, as manifested by reproductively normal females possessing non-functioning penises, has been reported for more than thirty species of dioecious neogastropods. This anomaly was shown to be unrelated to age or parasitism, but the geographic distribution of this phenomenon indicated that it was environmentally induced rather than genetically controlled. In a survey of N. lapillus populations along the New England Coast, Pondick found abnormal females at sites directly under the influence of industrial discharges, sewage effluent, or vessel-related activities. Histological sections revealed the presence of a penial duct. The purpose of this study was to determine if there were differences in metal levels in the snail populations studied by Pondick, with particular attention to metals associated with boating activity.

  18. Phylogeographic analyses reveal Transpontic long distance dispersal in land snails belonging to the Caucasotachea atrolabiata complex (Gastropoda: Helicidae).

    PubMed

    Neiber, Marco T; Sagorny, Christina; Sauer, Jan; Walther, Frank; Hausdorf, Bernhard

    2016-10-01

    The phylogeography and population structure of land snails belonging to the Caucasotachea atrolabiata complex in the Caucasus region was investigated to obtain a better understanding of diversification processes in this biodiversity hotspot. So far the complex has been classified into three species, C. atrolabiata from the north-western Caucasus, C. calligera from Transcaucasia and C. intercedens from the eastern Pontus Mountains. Phylogenetic (neighbor-net and neighbor-joining tree) as well as admixture analyses based on AFLP data showed that the complex consists of two population clusters corresponding to C. atrolabiata and C. calligera. The populations assigned to C. intercedens in fact represent hybrids consisting of different proportions of the genomes of C. atrolabiata and C. calligera. There is a broad transition zone between C. atrolabiata and C. calligera in the Pontic Mountains and a second transition zone in Abkhazia. Because of evidence for gene flow, it is suggested to classify the two aforementioned taxa as subspecies, namely C. a. atrolabiata and C. a. calligera. The presence of mitochondrial C. a. atrolabiata haplotypes in Turkey can only be explained by passive dispersal across the Black Sea. The distribution of C. a. atrolabiata and additional cases of land snails with disjunct Transpontic distribution patterns cannot be ascribed to a common cause but are results of long distance dispersal events at different times. PMID:27450782

  19. DNA barcodes and phylogenetic affinities of the terrestrial slugs Arion gilvus and A. ponsi (Gastropoda, Pulmonata, Arionidae)

    PubMed Central

    Breugelmans, Karin; Jordaens, Kurt; Adriaens, Els; Remon, Jean Paul; Cardona, Josep Quintana; Backeljau, Thierry

    2013-01-01

    Abstract The Iberian Peninsula is a region with a high endemicity of species of the terrestrial slug subgenus Mesarion. Many of these species have been described mainly on subtle differences in their proximal genitalia. It therefore remains to be investigated 1) whether these locally diverged taxa also represent different species under a phylogenetic species concept as has been shown for other Mesarion species outside the Iberian Peninsula, and 2) how these taxa are phylogenetically related. Here, we analysed DNA sequence data of two mitochondrial (COI and 16S) genes, and of the nuclear ITS1 region, to explore the phylogenetic affinities of two of these endemic taxa, viz. Arion gilvus Torres Mínguez, 1925 and A. ponsi Quintana Cardona, 2007. We also evaluated the use of these DNA sequence data as DNA barcodes for both species. Our results showed that ITS did not allow to differentiate among most of the Mesarion molecular operational taxonomic units (MOTUs) / morphospecies in Mesarion. Yet, the overall mean p-distance among the Mesarion MOTUs / morphospecies for both mtDNA fragments (16.7% for COI, 13% for 16S) was comparable to that between A. ponsi and its closest relative A. molinae (COI: 14.2%; 16S: 16.2%) and to that between A. gilvus and its closest relative A. urbiae (COI: 14.4%; 16S: 13.4%). Hence, with respect to mtDNA divergence, both A. ponsi and A. gilvus, behave as other Mesarion species or putative species-level MOTUs and thus are confirmed as distinct ‘species’. PMID:24453553

  20. Annotated type catalogue of the Orthalicoidea (Mollusca, Gastropoda) in the Museum für Naturkunde, Berlin.

    PubMed

    Breure, Abraham S H

    2013-01-01

    The type status is described of 96 taxa classified within the superfamily Orthalicoidea and present in the Mollusca collection of the Museum für Naturkunde der Humboldt-Universität zu Berlin. Lectotypes are designated for the following taxa: Orthalicus elegans Rolle, 1895; Bulimus maranhonensis Albers, 1854; Orthalicus nobilis Rolle, 1895; Orthalichus tricinctus Martens, 1893. Orthalicus sphinx tresmariae is introduced as new name for Zebra sphinx turrita Strebel, 1909, not Zebra quagga turrita Strebel, 1909. The following synonyms are established: Zebra crosseifischeri Strebel, 1909 = Orthalicus princeps fischeri Martens, 1893; Orthalicus isabellinus Martens, 1873 = Orthalicus bensoni (Reeve, 1849); Zebra zoniferus naesiotes Strebel, 1909 = Orthalicus undatus (Bruguière, 1789); Porphyrobaphe (Myiorthalicus) dennisoni pallida Strebel, 1909 = Hemibulimus dennisoni (Reeve, 1848); Zebra delphinus pumilio Strebel, 1909 = Orthalicus delphinus (Strebel, 1909); Orthalicus (Laeorthalicus) reginaeformis Strebel, 1909 = Corona perversa (Swainson, 1821); Bulimus (Eurytus) corticosus Sowerby III, 1895 = Plekocheilus (Eurytus) stuebeli Martens, 1885. The taxon Bulimus (Eudioptus) psidii Martens, 1877 is now placed within the family Sagdidae, tentatively in the genus Platysuccinea. Appendices are included with an index to all the types of Orthalicoidea extant (including those listed by Köhler 2007) and a partial list of letters present in the correspondence archives. PMID:23794831

  1. Food-induced esterase electromorphs in Carinarion spp. and their effects on taxonomic data analysis (Gastropoda, Pulmonata, Arionidae).

    PubMed

    Jordaens, K; Van Riel, P; Verhagen, R; Backeljau, T

    1999-03-01

    Nonspecific esterases (EST) are often used to measure genetic variation, yet they may be influenced by environmental factors such as food, climate and age. This may produce misleading similarity indices and genetic diversity estimates (i.e., clone or strain diversities in uniparental organisms). Therefore, polyacrylamide gel electrophoresis (PAGE) and isoelectric focusing (IEF) were used to investigate environmental effects on the EST variation in natural Carinarion populations, as well as in 45 individuals that were raised individually on carrots to produce offspring by selfing. Food effects on EST profiles in these progenies were examined by raising them on different food items (lettuce, nettle, or paper). Our results indicated that: (i) Arion (Carinarion) fasciatus and A. (C.) silvaticus show species-specific EST profiles, (ii) A. fasciatus-like outcrossers most probably are conspecific with A. fasciatus s.s., (iii) not all EST variation has a Mendelian basis since lettuce and nettle altered EST profiles, and (iv) food effects on EST profiles differed strongly between individuals. Although food-induced EST profiles did not affect taxonomic interpretations, they did inflate genetic diversity estimates and thus provided misleading population-genetic data.

  2. Effects of parasitism and environment on shell size of the South American intertidal mud snail Heleobia australis (Gastropoda)

    NASA Astrophysics Data System (ADS)

    Alda, Pilar; Bonel, Nicolás; Cazzaniga, Néstor J.; Martorelli, Sergio R.

    2010-04-01

    The aim of this work was to evaluate the effects of parasitism and certain environmental factors on the shell size of Heleobia australis (Hydrobiidae, Cochliopinae). We report sporocysts and metacercariae of Microphallus simillimus (Microphallidae, Trematoda) parasitizing the gonad and digestive gland of H. australis specimens from two sites of Bahía Blanca estuary, Argentina. The prevalence of infection was significantly higher (34.17% in winter and 68.14% in late spring) in snails from the outer estuary at Site 2 than in those from the inner estuary at Site 1 (5.88% and 4.71% respectively). The only known definitive host for this digenean is the white-backed stilt Himantopus melanurus (Recurvirostridae, Aves), most abundant in the estuary during winter. Parasitism by M. simillimus causes variations in the shell dimensions of H. australis, the shells of infected snails being narrower than those of uninfected snails. Snails from Site 2 were found in general to be significantly smaller than those at Site 1, possibly as a result of differences in environmental factors such as the degree of exposure to wave energy, the allocation of energy to reproduction rather than growth (induced by predation and/or parasitic castrators) and anthropogenic stressors.

  3. Ultrastructure and Glycoconjugate Pattern of the Foot Epithelium of the Abalone Haliotis tuberculata (Linnaeus, 1758) (Gastropoda, Haliotidae)

    PubMed Central

    Bravo Portela, I.; Martinez-Zorzano, V. S.; Molist- Perez, I.; Molist García, P.

    2012-01-01

    The foot epithelium of the gastropod Haliotis tuberculata is studied by light and electron microscopy in order to contribute to the understanding of the anatomy and functional morphology of the mollusks integument. Study of the external surface by scanning electron microscopy reveals that the side foot epithelium is characterized by a microvillus border with a very scant presence of small ciliary tufts, but the sole foot epithelium bears a dense field of long cilia. Ultrastructural examination by transmission electron microscopy of the side epithelial cells shows deeply pigmented cells with high electron-dense granular content which are not observed in the epithelial sole cells. Along the pedal epithelium, seven types of secretory cells are present; furthermore, two types of subepithelial glands are located just in the sole foot. The presence and composition of glycoconjugates in the secretory cells and subepithelial glands are analyzed by conventional and lectin histochemistry. Subepithelial glands contain mainly N-glycoproteins rich in fucose and mannose whereas secretory cells present mostly acidic sulphated glycoconjugates such as glycosaminoglycans and mucins, which are rich in galactose, N-acetyl-galactosamine, and N-acetyl-glucosamine. No sialic acid is present in the foot epithelium. PMID:22645482

  4. Philinidae, Laonidae and Philinorbidae (Gastropoda: Cephalaspidea: Philinoidea) from the northeastern Pacific Ocean and the Beaufort Sea (Arctic Ocean).

    PubMed

    Valdés, Ángel; Cadien, Donald B; Gosliner, Terrence M

    2016-08-08

    Based on morphological data a total of nine native species of Philinidae are recognized from the northeastern Pacific including the Bering Sea and the adjacent Arctic Ocean (Beaufort Sea). Four of them have been previously described: Philine ornatissima Yokoyama, 1927, Philine bakeri Dall, 1919, Philine polystrigma (Dall, 1908), and Philine hemphilli Dall, 1919. Five of them are new and described herein: Philine mcleani sp. nov., Philine baxteri sp. nov., Philine malaquiasi sp. nov., Philine wareni sp. nov., and Philine harrisae sp. nov. These species display a substantial degree of variation in internal and external morphological traits (i.e., presence/absence of gizzard plates, different radular structure and tooth morphology, various reproductive anatomical features) and it is likely that they belong to different clades (genera). However, in the absence of a comprehensive phylogeny for Philine, they are here provisionally regarded as Philine sensu lato. In addition to the nine native species, two introduced species: Philine orientalis A. Adams, 1854 and Philine auriformis Suter, 1909 are here illustrated and compared to the native species to facilitate identification. Finally, two species previously considered members of Philinidae are examined anatomically and confirmed as members of Laonidae, Laona californica (Willett, 1944) and Philinorbidae, Philinorbis albus (Mattox, 1958), based on morphological data.

  5. Annotated type catalogue of the Megaspiridae, Orthalicidae, and Simpulopsidae (Mollusca, Gastropoda, Orthalicoidea) in the Natural History Museum, London

    PubMed Central

    Breure, Abraham S. H.; Ablett, Jonathan D.

    2015-01-01

    Abstract The type status is described for 65 taxa of the Orthalicoidea, classified within the families Megaspiridae (14), Orthalicidae (30), and Simpulopsidae (20); one taxon is considered a nomen inquirendum. Lectotypes are designated for the following taxa: Helix brephoides d’Orbigny, 1835; Simpulopsis cumingi Pfeiffer, 1861; Bulimulus (Protoglyptus) dejectus Fulton, 1907; Bulimus iris Pfeiffer, 1853. The type status of Bulimus salteri Sowerby III, 1890, and Strophocheilus (Eurytus) subirroratus da Costa, 1898 is now changed to lectotype according Art. 74.6 ICZN. The taxa Bulimus loxostomus Pfeiffer, 1853, Bulimus marmatensis Pfeiffer, 1855, Bulimus meobambensis Pfeiffer, 1855, and Orthalicus powissianus var. niveus Preston 1909 are now figured for the first time. The following taxa are now considered junior subjective synonyms: Bulimus marmatensis Pfeiffer, 1855 = Helix (Cochlogena) citrinovitrea Moricand, 1836; Vermiculatus Breure, 1978 = Bocourtia Rochebrune, 1882. New combinations are: Kuschelenia (Bocourtia) Rochebrune, 1882; Kuschelenia (Bocourtia) aequatoria (Pfeiffer, 1853); Kuschelenia (Bocourtia) anthisanensis (Pfeiffer, 1853); Kuschelenia (Bocourtia) aquila (Reeve, 1848); Kuschelenia (Bocourtia) badia (Sowerby I, 1835); Kuschelenia (Bocourtia) bicolor (Sowerby I, 1835); Kuschelenia (Bocourtia) caliginosa (Reeve, 1849); Kuschelenia (Bocourtia) coagulata (Reeve, 1849); Kuschelenia (Bocourtia) cotopaxiensis (Pfeiffer, 1853); Kuschelenia (Bocourtia) filaris (Pfeiffer, 1853); Kara indentata (da Costa, 1901); Clathrorthalicus magnificus (Pfeiffer, 1848); Simpulopsis (Eudioptus) marmartensis (Pfeiffer, 1855); Kuschelenia (Bocourtia) nucina (Reeve, 1850); Kuschelenia (Bocourtia) ochracea (Morelet, 1863); Kuschelenia (Bocourtia) peaki (Breure, 1978); Kuschelenia (Bocourtia) petiti (Pfeiffer, 1846); Clathrorthalicus phoebus (Pfeiffer, 1863); Kuschelenia (Bocourtia) polymorpha (d’Orbigny, 1835); Scholvienia porphyria (Pfeiffer, 1847); Kuschelenia (Bocourtia) purpurata (Reeve, 1849); Kuschelenia (Bocourtia) quechuarum Crawford, 1939; Quechua salteri (Sowerby III, 1890); Kuschelenia (Bocourtia) subfasciata Pfeiffer, 1853; Clathrorthalicus victor (Pfeiffer, 1854). In an addedum a lectotype is being designated for Bulimulus (Drymaeus) interruptus var. pallidus Preston, 1909. An index is included to all taxa mentioned in this paper and the preceding ones in this series (Breure and Ablett 2011, 2012, 2014). PMID:25632243

  6. Shallow water heterobranch sea slugs (Gastropoda: Heterobranchia) from the Región de Atacama, northern Chile

    PubMed Central

    Valdés, Ángel

    2016-01-01

    The coast of northern Chile has been sparsely studied in regards to its invertebrate fauna, with just a few works reviewing the distribution of local mollusks. This work presents a survey of the shallow water heterobranch sea slugs currently occurring around the port of Caldera (27 °S), in the Región de Atacama, northern Chile. Eight species of sea slugs were found in this study: Aplysiopsis cf. brattstroemi (Marcus, 1959), Baptodoris peruviana (d’Orbigny, 1837), Diaulula variolata (d’Orbigny, 1837), Doris fontainii d’Orbigny, 1837, Onchidella marginata (Couthouy in Gould, 1852), Phidiana lottini (Lesson, 1831), Tyrinna delicata (Abraham, 1877) and the new species Berthella schroedli sp. nov., described herein. All of the species found in the area are endemic to South America, having distributions in the southeastern Pacific and South Atlantic Oceans, from Ancash, Perú to Peninsula Valdés, Argentina, and two of them represent species which are endemic to the Chilean coasts (Aplysiopsis cf. brattstroemi and Berthella schroedli). The finding of a previously undescribed species emphasizes the need of further surveys, particularly in subtidal and deeper waters, in order to improve the knowledge on this neglected fauna in Atacama. PMID:27168975

  7. Annotated type catalogue of Bothriembryon (Mollusca, Gastropoda, Orthalicoidea) in Australian museums, with a compilation of types in other museums

    PubMed Central

    Breure, Abraham S.H.; Whisson, Corey S.

    2012-01-01

    Abstract Type material of 41 Australian Bothriembryon taxa present in Australian museums is critically listed, indicating systematic issues that need to be resolved in further studies. Information on additional type material of 22 taxa in non-Australian museums is compiled. The seven fossil taxa known so far are included in this catalogue. Based on the current systematic position, 38 species are treated in this paper. Bothriembryon jacksoni Iredale, 1939, Bothriembryon notatus Iredale, 1939, Bothriembryon praecelsus Iredale, 1939 and Bothriembryon serpentinus Iredale, 1939 are elevated to species level. Bothriembryon gratwicki (Cox, 1899) is listed as status to be determined. PMID:22679384

  8. Revision of Partulidae (Gastropoda, Stylommatophora) of Palau, with description of a new genus for an unusual ground-dwelling species.

    PubMed

    Slapcinsky, John; Kraus, Fred

    2016-01-01

    We describe a new stylommatophoran land snail of the family Partulidae from Palau. The new species has a combination of morphological and ecological characters that do not allow its placement in any existing partulid genus, so we describe a new genus for it. The new genus is characterized by a large (18-23 mm) obese-pupoid shell; smooth protoconch; teleoconch with weak and inconsistent, progressively stronger, striae; last half of body whorl not extending beyond the penultimate whorl; widely expanded and reflexed peristome; relatively long penis, with longitudinal pilasters that fuse apically into a fleshy ridge that divides the main chamber from a small apical chamber; and vas deferens entering and penial-retractor muscle attaching at the apex of the penis. Unlike all other partulids, the new species is strictly associated with rocks in contact with the ground. Comparing the other three Palauan species - currently assigned to Partula - to our new genus and to other partulids makes it clear that they require their own genus because their morphology is quite different from that of true Partula and from that of all other genera. Hence, we resurrect the name Palaopartula Pilsbry for these snails. PMID:27667931

  9. The Pleistocene glaciations and the evolutionary history of the polytypic snail species Arianta arbustorum (Gastropoda, Pulmonata, Helicidae).

    PubMed

    Gittenberger, E; Piel, W H; Groenenberg, D S J

    2004-01-01

    The evolutionary history of the snail Arianta arbustorum is controversial. This diverse, polytypic species has two distinct forms: one, with a globular shell and closed umbilicus, is found from lowland to high altitudes; the other, with a depressed shell and open umbilicus, is found at a few scattered, high altitude localities. What is the origin of these two forms? Some believe that the depressed shell is a recent, local, ecotypic adaptation to alpine environments. Others believe that this form is a relic of an ancestral condition that may have survived the Pleistocene glaciations on nunatak-like montane refugia, while the globular shell is a derived condition and its presence at high altitudes follows post-Pleistocene recolonisation. We analysed a portion of the mitochondrial gene cytochrome oxidase I for 100 snails of the species A. arbustorum, three additional Arianta species, and nine outgroup taxa from five genera, in order to understand the phylogeographic history of the species. Despite some confounding artefacts that are likely due to introgression among the morphological forms, the resulting phylogeny shows that the depressed shell is plesiomorphic, while the globular shell is derived. Moreover, their disparate histories suggest that the depressed shell variety survived the glaciations in pockets of alpine refugia, while the globular shell variety recolonised the alpine environment post-glacially.

  10. [Some adaptations of Monodonta turbinata (born, 1780) (Gastropoda, Prosobranchia, Trochidae) to feeding and habitation in the littoral zone].

    PubMed

    Aliakrinskaia, I O

    2010-01-01

    The basic morphological, ethological, and physiological-biochemical adaptations of Monodonta turbinata to survival in the littoral zone were investigated in this work. Quantitative estimation of myoglobin content in radular tissues of mollusks inhabiting the Mediterranean Sea Basin has been carried out.

  11. Behavioural and histological effects of atrazine on freshwater molluscs (Physa acuta Drap. and Ancylus fluviatilis Müll. Gastropoda).

    PubMed

    Rosés, N; Poquet, M; Muñoz, I

    1999-01-01

    This study examines the direct and indirect effects of atrazine on two grazer species--Physa acuta and Ancylus fluviatilis--as assessed by changes in mortality rates, biomass, searching behaviour and histological properties. No direct effects were observed in the acute toxicity test (48 h) with 0.02, 0.2, 2, 10 and 20 mg l(-1) of atrazine. A chronic toxicity test (18 days) performed in six experimental channels with 15 microg l(-1) of atrazine showed significant changes in grazer behaviour, increased searching velocity and different movement patterns in animals exposed to herbicide. No significant effects were observed in rates of mortality and biomass. Kidney cells of Physa acuta displayed an important cell lysis when animals were exposed to 0.1 mg l(-1) of atrazine for 10 days, and this effect was not reversed after a decontamination process. These results provide evidence of behavioural and structural changes in freshwater molluscs due to a subacute atrazine concentration.

  12. Seasonal variations in maternal provisioning of Crepidula fornicata (Gastropoda): fatty acid composition of females, embryos and larvae.

    PubMed

    Leroy, Fanny; Meziane, Tarik; Riera, Pascal; Comtet, Thierry

    2013-01-01

    Recruitment success of marine invertebrate populations not only depends on the number of recruits but also on their quality which affects their survival. In species characterized by a mixed development (encapsulated embryonic development and release of planktotrophic larvae), the offspring quality depends on both maternal provisioning and larval feeding. Here, we investigated potential changes of maternal provisioning over the whole reproductive period in a gastropod with a mixed development: Crepidula fornicata. In its introduction area, C. fornicata reproduces from February to October, which implies that both adults and larvae are exposed to different food availabilities. Maternal provisioning was assessed by measuring the fatty acid (FA) composition of females, encapsulated embryos and larvae, in February, May, July and September 2009. FA are essential resources for the development of embryos and larvae, and are key biomarkers of offspring quality. Our results showed differences in FA composition between muscles, visceral masses, and encapsulated embryos. In particular, FA composition of embryos was similar to that of the visceral mass. Seasonal variations in FA composition were observed: in the middle of the reproductive season (May and July), female tissues and embryos showed a higher proportion of polyunsaturated fatty acids and especially ω3, as compared to the beginning and end of the reproductive season (February and September). This showed that through maternal provisioning the quality of C. fornicata offspring was higher in the middle of the reproductive season. Whether this would result in an increase of recruitment success and juvenile performance would require further investigations.

  13. mtDNA ribosomal gene phylogeny of sea hares in the genus Aplysia (Gastropoda, Opisthobranchia, Anaspidea): Implications for comparative neurobiology

    SciTech Connect

    Medina, Monica; Collins, Timothy M.; Walsh, Patrick J.

    2000-08-10

    Sea hares within the genus Aplysia are important neurobiological model organisms, and as studies based on different Aplysia species appear in the literature, a phylogenetic framework has become essential. We present a phylogenetic hypothesis for this genus, based on portions of two mitochondrial genes (12S and 16S). In addition, we reconstruct the evolution of several behavioral characters of interest to neurobiologists in order to illustrate the potential benefits of a phylogeny for the genus Aplysia. These benefits include the determination of ancestral traits, the direction and timing of evolution of characters, prediction of the distribution of traits, and identification of cases of independent acquisition of traits within lineages. This last benefit may prove especially useful in understanding the linkage between behaviors and their underlying neurological basis.

  14. Seven new hypselostomatid species from China, including some of the world’s smallest land snails (Gastropoda, Pulmonata, Orthurethra)

    PubMed Central

    Páll-Gergely, Barna; Hunyadi, András; Jochum, Adrienne; Asami, Takahiro

    2015-01-01

    Abstract Seven new species of Hypselostomatidae are described from the Chinese province Guangxi: Angustopila dominikae Páll-Gergely & Hunyadi, sp. n., Angustopila fabella Páll-Gergely & Hunyadi, sp. n., Angustopila subelevata Páll-Gergely & Hunyadi, sp. n., Angustopila szekeresi Páll-Gergely & Hunyadi, sp. n., Hypselostoma socialis Páll-Gergely & Hunyadi, sp. n., Hypselostoma lacrima Páll-Gergely & Hunyadi, sp. n. and Krobylos sinensis Páll-Gergely & Hunyadi, sp. n. The latter species is reported from three localities. All other new species are known only from the type locality. Specimens nearly identical to the type specimens of Angustopila huoyani Jochum, Slapnik & Páll-Gergely, 2014 were found in a cave in northern Guangxi, 500 km from the type locality. Adult individuals of Angustopila subelevata sp. n. (shell height = 0.83–0.91 mm, mean = 0.87 mm) and Angustopila dominikae sp. n. (shell height of the holotype = 0.86 mm) represent the smallest known members of the Hypselostomatidae, and thus are amongst the smallest land snails ever reported. We note that Pyramidula laosensis Saurin, 1953 might also belong to Krobylos. Paraboysidia neglecta van Benthem Jutting, 1961, which was previously included in Angustopila, is classified in Hypselostoma. PMID:26478698

  15. No evidence for a culturable bacterial tetrodotoxin producer in Pleurobranchaea maculata (Gastropoda: Pleurobranchidae) and Stylochoplana sp. (Platyhelminthes: Polycladida).

    PubMed

    Salvitti, Lauren R; Wood, Susanna A; McNabb, Paul; Cary, Stephen Craig

    2015-01-28

    Tetrodotoxin (TTX) is a potent neurotoxin found in the tissues of many taxonomically diverse organisms. Its origin has been the topic of much debate, with suggestions including endogenous production, acquisition through diet, and symbiotic bacterial synthesis. Bacterial production of TTX has been reported in isolates from marine biota, but at lower than expected concentrations. In this study, 102 strains were isolated from Pleurobranchaea maculata (Opisthobranchia) and Stylochoplana sp. (Platyhelminthes). Tetrodotoxin production was tested utilizing a recently developed sensitive method to detect the C9 base of TTX via liquid chromatography-mass spectrometry. Bacterial strains were characterized by sequencing a region of the 16S ribosomal RNA gene. To account for the possibility that TTX is produced by a consortium of bacteria, a series of experiments using marine broth spiked with various P. maculata tissues were undertaken. Sixteen unique strains from P. maculata and one from Stylochoplana sp. were isolated, representing eight different genera; Pseudomonadales, Actinomycetales, Oceanospirillales, Thiotrichales, Rhodobacterales, Sphingomonadales, Bacillales, and Vibrionales. Molecular fingerprinting of bacterial communities from broth experiments showed little change over the first four days. No C9 base or TTX was detected in isolates or broth experiments (past day 0), suggesting a culturable microbial source of TTX in P. maculata and Stylochoplana sp. is unlikely.

  16. Opisthobranchia (Mollusca, Gastropoda) – more than just slimy slugs. Shell reduction and its implications on defence and foraging

    PubMed Central

    Wägele, Heike; Klussmann-Kolb, Annette

    2005-01-01

    Background In general shell-less slugs are considered to be slimy animals with a rather dull appearance and a pest to garden plants. But marine slugs usually are beautifully coloured animals belonging to the less-known Opisthobranchia. They are characterized by a large array of interesting biological phenomena, usually related to foraging and/or defence. In this paper our knowledge of shell reduction, correlated with the evolution of different defensive and foraging strategies is reviewed, and new results on histology of different glandular systems are included. Results Based on a phylogeny obtained by morphological and histological data, the parallel reduction of the shell within the different groups is outlined. Major food sources are given and glandular structures are described as possible defensive structures in the external epithelia, and as internal glands. Conclusion According to phylogenetic analyses, the reduction of the shell correlates with the evolution of defensive strategies. Many different kinds of defence structures, like cleptocnides, mantle dermal formations (MDFs), and acid glands, are only present in shell-less slugs. In several cases, it is not clear whether the defensive devices were a prerequisite for the reduction of the shell, or reduction occurred before. Reduction of the shell and acquisition of different defensive structures had an implication on exploration of new food sources and therefore likely enhanced adaptive radiation of several groups. PMID:15715915

  17. Identification of two carbonic anhydrases in the mantle of the European Abalone Haliotis tuberculata (Gastropoda, Haliotidae): phylogenetic implications.

    PubMed

    LE Roy, Nathalie; Marie, Benjamin; Gaume, Béatrice; Guichard, Nathalie; Delgado, Sidney; Zanella-Cléon, Isabelle; Becchi, Michel; Auzoux-Bordenave, Stéphanie; Sire, Jean-Yves; Marin, Frédéric

    2012-07-01

    Carbonic anhydrases (CAs) represent a diversified family of metalloenzymes that reversibly catalyze the hydration of carbon dioxide. They are involved in a wide range of functions, among which is the formation of CaCO(3) skeletons in metazoans. In the shell-forming mantle tissues of mollusks, the location of the CA catalytic activity is elusive and gives birth to contradicting views. In the present paper, using the European abalone Haliotis tuberculata, a key model gastropod in biomineralization studies, we identified and characterized two CAs (htCA1 and htCA2) that are specific of the shell-forming mantle tissue. We analyzed them in a phylogenetic context. Combining various approaches, including proteomics, activity tests, and in silico analyses, we showed that htCA1 is secreted but is not incorporated in the organic matrix of the abalone shell and that htCA2 is transmembrane. Together with previous studies dealing with molluskan CAs, our findings suggest two possible modes of action for shell mineralization: the first mode applies to, for example, the bivalves Unio pictorum and Pinctada fucata, and involves a true CA activity in their shell matrix; the second mode corresponds to, for example, the European abalone, and does not include CA activity in the shell matrix. Our work provides new insight on the diversity of the extracellular macromolecular tools used for shell biomineralization study in mollusks.

  18. The genus Pustulatirus Vermeij and Snyder, 2006 (Gastropoda: Fasciolariidae: Peristerniinae) in the western Atlantic, with descriptions of three new species.

    PubMed

    Lyons, William G; Snyder, Martin Avery

    2013-01-01

    Western Atlantic species of the New World genus Pustulatirus Vermeij and Snyder, 2006 are revised. Types of previously named taxa are figured. Species recognized as valid include P. attenuata (Reeve, 1847), range uncertain; P. eppi (Melvill, 1891), Curagao; P. ogum (Petuch, 1979), northeastern Brazil; and P. virginensis (Abbott, 1958), Bahama Islands and eastern Caribbean Sea to Aruba. Latirus karinae Nowell-Usticke, 1969 is confirmed as ajunior subjective synonym of P. virginensis. Syrinx annulata Röding, 1798, treated as a Caribbean Pustulatirus by Vermeij and Snyder (2006), and Latirus annulatus Melvill, 1891 are regarded as species inquirenda. Three new species are described: P biocellatus, northeastern Brazil; P. utilaensis, Bay Islands, Honduras and northwestern Panamá; and P. watermanorum, Honduras continental shelf and offshore Colombian banks. Most western Atlantic Pustulatirus shells exhibit little intraspecific variability in morphology or color and occur within rather precise, well-defined ranges; an exception is P. virginensis, whose shells exhibit much variability in size, morphology and color.

  19. Polycyclic aromatic hydrocarbons in Haliotis tuberculata (Linnaeus, 1758) (Mollusca, Gastropoda): Considerations on food safety and source investigation.

    PubMed

    Conte, Francesca; Copat, Chiara; Longo, Sabrina; Conti, Gea Oliveri; Grasso, Alfina; Arena, Giovanni; Dimartino, Angela; Brundo, Maria Violetta; Ferrante, Margherita

    2016-08-01

    Polycyclic aromatic hydrocarbons were analyzed in wild specimens of Haliotis tuberculata from three sites of the Sothern Ionian Sea. The species Ht is commonly found at these sites and has significant commercial value. Main results revealed mean values of benzo(a)pyrene higher than the threshold set by Regulation No. 835/2011/EU in all sampling sites and the sum of selected PAHs, expressed as ΣPAH4 by EC Regulation, were below the limit set by the same Regulation in ME and VSG. We found generally higher concentrations than literature finding, especially for low molecular weight PAHs, and results of diagnostic ratios highlighted both pyrolytic and petrogenic sources. The potential human health risks due consumption of Ht by local inhabitants have been assessed by exposure daily intake (EDI), target hazard quotient (THQ) and lifetime cancer risk (CR). EDI values were below the intake range reviewed by EFSA for each class of contaminant. BaP daily intake was below the value of 10 ng/Kg/day, suggested by JFCFA, and CRBaP was slightly higher than the acceptable risk level (ARL) of 1×10(-5). Conversely, target hazard quotient (THQ) resulted always below 1, thus the risk to develop chronic systemic effects due naphthalene, acenaphthene, fluorene, anthracene, fluoranthene and pyrene was low. PMID:27235950

  20. Phylogeographic patterns in New Zealand and temperate Australian cantharidines (Mollusca: Gastropoda: Trochidae: Cantharidinae): Trans-Tasman divergences are ancient.

    PubMed

    Donald, Kirsten M; Spencer, Hamish G

    2016-07-01

    Current taxonomic treatments of New Zealand and temperate Australian members of the gastropod subfamily Cantharidinae imply that species on either side of the Tasman Sea are closely related and, in some cases, congeneric. Such a close relationship, however, entails a relatively recent divergence of Australian and New Zealand lineages, which seems inconsistent with what is known about cantharidine larval development in general. In order to address these issues, mitochondrial and nuclear DNA sequences were used to ascertain how cantharidine genera became established over the wide geographical range of temperate Australia and New Zealand, including their subantarctic islands. Our robust and dated phylogenies (based on 16S, COI, 12S and 28S sequences) revealed that Australian and New Zealand species fall into endemic clades that have been separated for, at most, 35million years. This divergence date postdates a vicariant split by around 50million years and we suggest that, once again, long-distance trans-Tasman dispersal has played a pivotal role in molluscan evolution in this part of the world. Our results also show that the current classification requires revision. We recognize three genera (Cantharidus [comprising 2 subgenera: Cantharidus s.str. and Pseudomargarella n. subgen.], Micrelenchus [comprising 2 subgenera: Micrelenchus s.str. and Mawhero] and Roseaplagis n. gen.) for New Zealand cantharidine species. In our dated BEAST tree, these genera form a clade with the endemic Australian Prothalotia and South African Oxystele. Other temperate Australian cantharidines in our study fall into previously recognized genera (Phasianotrochus, Thalotia, Calthalotia), which are all quite distinct from Cantharidus in spite of some authors considering various of them to be possible synonyms. Finally, we remove the Australian genus Cantharidella from the Cantharidinae to the subfamily Trochinae and erect a new genus, Cratidentium n. gen., also in the Trochinae, to accommodate several Australian species previously considered to belong to Cantharidella. PMID:27118181

  1. The occurrence of Clithon retropictus (v. Martens, 1879) (Gastropoda: Neritidae) in an unusual habitat, northern Jeju Island, Republic of Korea

    NASA Astrophysics Data System (ADS)

    Noseworthy, Ronald G.; Lee, Hee-Jung; Choi, Kwang-Sik

    2013-09-01

    Clithon retropictus is a neritid gastropod inhabiting mainly brackish water. Currently this species has been listed as a second grade endangered species of wildlife in Korea by the Ministry of Environment, due to the decrease in its population size. C. retropictus has previously been identified from estuaries on the south coast of Korea. In Jeju Island, this species has been reported only from the south coast. However, a population has recently been discovered on the north coast of the island in an apparently new type of habitat, under rocks adjacent to a dry riverbed on a muddy substrate. C. retropictus was found to be aggregated under some of the larger rocks, and the habitat was located near the high tide line. The present study reports some possible reasons for the occurrence of the population in this unusual habitat, and provides useful information on the biometry and population size which can be used in the management of this endangered species.

  2. Description and evaluation of imposex in Strombus canarium Linnaeus, 1758 (Gastropoda, Strombidae): a potential bio-indicator of tributyltin pollution.

    PubMed

    Cob, Zaidi Che; Arshad, Aziz; Bujang, Japar Sidik; Abd Ghaffar, Mazlan

    2011-07-01

    Strombus canarium Linnaeus, 1758 is an important gastropod species within the study area and was traditionally collected for food by the locals. The objective of the present study is to assess the incidence of imposex and its severity in this species. Adult conchs were sampled during their main reproductive period, from October 2005 to January 2006, at Sungai Pulai estuary, Johor Straits, Malaysia. A total of 32.81% of adult females showed imposex characteristics, with varying degrees of severity though. The relative penis size (RPS) index ranged from 1.74 to 33.29 (mean = 13.40 ± 2.27, n = 21), while the relative penis length (RPL) index ranged from 6.28 to 55.19 (mean = 25.83 ± 3.33, n = 21). The use of vas deferens sequence (VDS) index was however cannot be applied as the presence of egg groove obscured any vas deferens development in affected females. Sequence of imposex (male penis) development in female conch, from merely a small stump to an advance male penis homologous was therefore carefully analyzed and described, and an alternative imposex classification scheme was proposed. S. canarium can be a good indicator for monitoring of organotin pollution within the study area. However, more studies are needed in order to further develop and test its validity and application, such as its correlation with levels of pollutant within the tissues and the environment, as well as its application on other Strombus species.

  3. [Genetic diversity in two populations of the snail Strombus gigas (Gastropoda: Strombidae) from Yucatan, Mexico, using microsatellite].

    PubMed

    Zamora-Bustillos, Roberto; Rodríguez-Canul, Rossanna; García de León, Francisco J; Tello Cetina, Jorge

    2011-09-01

    The pink conch Strombus gigas is an important fisheries resource in the Caribbean region, including the Yucatán Peninsula. We analyzed the genetic diversity and genetic structure of two populations (Alacranes Reef and Chinchorro Bank) with the use of five microsatellite molecular markers. The results indicate that the two populations are in the same rank of genetic diversity (He), from 0.613 to 0.692. Significant deviation from H-WE was observed in the both populations due to deficit to heterozygotes, this was attributed to inbreeding as a consequence of over-fishing; nevertheless, other possible causes considered are mixing of individuals from two or more populations, and the existence of null alleles. Levels of genetic differentiation indicated the existence of a single homogenous population in the Yucatan Peninsula (F(ST) de 0.003, p = 0.49), which fits with highest levels of gene flow is significant (2.3 individuals) between both populations. Results from this study support the hypothesis that S. gigas is part of a single panmictic population in the Yucatan Peninsula; therefore, this fishery resource should be regulated the same way for both areas.

  4. A molecular phylogeny of the Littorininae (Gastropoda: Littorinidae): unequal evolutionary rates, morphological parallelism, and biogeography of the Southern Ocean.

    PubMed

    Williams, S T; Reid, D G; Littlewood, D T J

    2003-07-01

    A molecular phylogeny is presented for the subfamily Littorininae (including representatives of all subgeneric taxa and all members of a group of southern-temperate species formerly classified as 'Nodilittorina'), based on sequence data from two nuclear (18S rRNA, 28S rRNA) and two mitochondrial (12S rRNA, CO1) genes. The phylogeny shows considerable disagreement with earlier hypotheses derived from morphological data. In particular, 'Nodilittorina' is polyphyletic and is here divided into four genera (Echinolittorina, Austrolittorina, Afrolittorina new genus, and the monotypic Nodilittorina s.s.). The phylogenetic relationships of 'Littorina' striata have been controversial and it is here transferred to the genus Tectarius, a surprising relationship for which there is little morphological support. The relationships of the enigmatic Mainwaringia remain poorly resolved, but it is not a basal member of the subfamily. The two living species of Mainwaringia are remarkable for a greatly elevated rate of evolution in all four genes examined; it is suggested that this may be connected with their protandrous hermaphroditism, which is unique in the family. The molecular phylogeny provides a new framework for the adaptive radiation of the Littorininae, showing more frequent shifts between habitats and climatic regimes than previously suspected, and striking parallelism of morphological characters. The fossil record of littorinids is poor, but ages of clades are estimated using a calibration based on a Lower Eocene age of the genus Littoraria. Using these estimates, the antitropical distribution of Littorina and Afrolittorina is an ancient pattern of possibly Cretaceous age. The five members of Austrolittorina show a Gondwanan distribution in Australia, New Zealand, and South America. Based on the morphological uniformity within this clade, relatively recent (Plio-Pleistocene) trans-Pacific dispersal events seemed a likely explanation, as proposed for numerous other congeneric marine taxa. However, molecular estimation of ages of divergence suggest an initial vicariance between Australian and South American lineages at 40-73Ma, contemporary with the later stages of fragmentation of the Gondwanan supercontinent, followed by more recent (but still mid-Cenozoic) dispersal events across the Tasman Sea and the Pacific Ocean. Afrolittorina is another Cretaceous clade, now restricted to southern Africa and southern Australia, but divergence between these lineages (29-55Ma) post-dates Gondwanan fragmentation. Within both Austrolittorina and Afrolittorina all sister-species divergences are estimated to fall in the range 10-47Ma, so that there is no evidence for speciation events in the Plio-Pleistocene. PMID:12801472

  5. A new member of troglobitic Carychiidae, Koreozospeum nodongense gen. et sp. n. (Gastropoda, Eupulmonata, Ellobioidea) is described from Korea

    PubMed Central

    Jochum, Adrienne; Prozorova, Larisa; Sharyi-ool, Mariana; Páll-Gergely, Barna

    2015-01-01

    Abstract A new genus of troglobitic Carychiidae Jeffreys, 1830 is designated from Nodong Cave, North Chungcheong Province, Danyang, South Korea. This remarkable find represents a great range extension and thus, a highly distant distribution of troglobitic Carychiidae in Asia. The Zospeum-like, carychiid snails were recently included, without a formal description, in records documenting Korean malacofauna. The present paper describes Koreozospeum Jochum & Prozorova, gen. n. and illustrates the type species, Koreozospeum nodongense Lee, Prozorova & Jochum, sp. n. using novel Nano-CT images, including a video, internal shell morphology, SEM and SEM-EDX elemental compositional analysis of the shell. PMID:26312456

  6. Postembryonic stages of Nucellicola holmanae Lamb et al., 1996 (copepoda, poecilostomatoida), an endoparasite of the dog whelk Nucella lapillus (gastropoda)

    NASA Astrophysics Data System (ADS)

    Lamb, E. J.; Boxshall, G. A.; Mill, P. J.; Grahame, J.

    1998-06-01

    The external morphology of the first three larval stages of Nucellicola holmanae is described. These stages were cultured from eggs found with the adults in the viscera of dog whelks collected from Robin Hood's Bay, North Yorkshire. The nauplius develops within the whelk. It moults to a metanauplius which is released as a free-swimming stage. The metanauplius moults to a free copepodid stage which exhibits a combination of characters typical of the first, second and third copepodid stages of other poecilostomatoid copepods. The infective copepodid stage which locates and penetrates the host is visible through the integument of this free-swimming copepodid.

  7. Surviving the Messinian Salinity Crisis? Divergence patterns in the genus Dendropoma (Gastropoda: Vermetidae) in the Mediterranean Sea.

    PubMed

    Calvo, Marta; Alda, Fernando; Oliverio, Marco; Templado, José; Machordom, Annie

    2015-10-01

    Four genetically distinct clades were recently described under the name Dendropoma petraeum, a Mediterranean endemic vermetid gastropod. The aim of this work is to date the processes that drove to the diversification within this taxon and to relate them to the corresponding historical events occurred in the Mediterranean Sea. Sequences from mitochondrial and nuclear markers were obtained from specimens collected in 29 localities spanning over 4000km across the entire distribution range of D. petraeum species complex. The phylogenetic and coalescent-based analyses confirmed the four well-supported and largely differentiated lineages of D. petraeum, clearly delimited geographically along a west-east axis within the Mediterranean Sea: Western, Tyrrhenian-Sicilian, Ionian-Aegean and Levantine lineages. Divergence time estimates, obtained using a range of known substitution rates for other marine gastropods, indicated two main stages of diversification. In the first period (between 9.5 and 4.5mya), the ancestral D. petraeum diverged into the current four lineages. The most recent period occurred between 3.72 and 0.66mya in the late Pliocene-early Pleistocene, and included the main within-lineage diversification events. Therefore, if the divergence time between the major lineages of Dendropoma in the Mediterranean actually predated or coincided with the Messinian Salinity Crisis, then they should have survived to this dramatic period within the Mediterranean, as supported by Bayes Factors model comparison. Conversely, if the divergence started after the crisis, congruent with the idea that no true marine organism survived the Messinian Salinity Crisis, then our results indicate substitution rates of Dendropoma much higher than usual (5.16% per million years for COI, 3.04% for 16S). More recent climate changes seem to have conditioned the demographic history of each lineage differently. While Western and Tyrrhenian-Sicilian lineages both underwent an increase in their effective population sizes from 1.5 to 0.6mya coinciding with a long interglacial period, the Ionian-Aegean and Levantine lineages showed constant effective population sizes since 2-2.5mya, suggesting that these eastern lineages might represent small and relict populations surviving the subsequent Quaternary glaciations in isolated refugia.

  8. Revision of the Recent Mediterranean species of Mitromorpha Carpenter, 1865 (Gastropoda, Conoidea, Mitromorphidae) with the description of seven new species.

    PubMed

    Amati, Bruno; Smriglio, Carlo; Oliverio, Marco

    2015-01-01

    The Mediterranean species of the genus Mitromorpha Carpenter, 1865 as currently conceived, are herein reviewed. The genus is represented in the Mediterranean Sea by eleven species, of which seven are here described as new, all included conservatively in the subgenus Mitrolumna Bucquoy, Dautzenberg & Dollfus, 1883: Mitromorpha (Mitrolumna) columbellaria (Scacchi, 1836), Mitromorpha (Mitrolumna) olivoidea (Cantraine, 1835), Mitromorpha (Mitrolumna) karpathoensis (Nordsieck, 1969), Mitromorpha (Mitrolumna) wilhelminae (van Aartsen, Menkhorst & Gittenberger, 1984), Mitromorpha (Mitrolumna) alyssae n. sp., Mitromorpha (Mitrolumna) bogii n. sp., Mitromorpha (Mitrolumna) cossyrae n. sp., Mitromorpha (Mitrolumna) nofronii n. sp., Mitromorpha (Mitrolumna) mariottinii n. sp., Mitromorpha (Mitrolumna) mifsudi n. sp., and Mitromorpha (Mitrolumna) tricolorata n. sp. Neotypes are designated for: Mitra columbellaria Scacchi, 1836, [currently Mitromorpha columbellaria (Scacchi, 1836) comb. nov.], and Mitrolumna algeriana Pallary, 1900 ex Monterosato ms. [currently Mitromorpha algeriana (Pallary, 1900) comb. nov.] considered as a synonym of Mitromorpha columbellaria (Scacchi, 1836). The latter is the oldest available name for the most common and widespread Mediterranean species of Mitromorpha. A lectotype is selected for Mitra leontocroma Brusina, 1866 [currently Mitromorpha leontocroma (Brusina, 1866) comb. nov.], previously considered as a junior synonym of Mitromorpha olivoidea (Cantraine, 1835) but here considered as a junior synonym of Mitromorpha columbellaria (Scacchi, 1836). Mitromorpha melitensis (Mifsud, 1993) is a synonym of Mitromorpha olivoidea (Cantraine, 1835). Mitromorpha mediterranea Mifsud, 2001 is a synonym of Mitromorpha columbellaria (Scacchi, 1836).

  9. Developmental toxicity of metaldehyde in the embryos of Lymnaea stagnalis (Gastropoda: Pulmonata) co-exposed to the synergist piperonyl butoxide.

    PubMed

    Hallett, Katrina C; Atfield, Andrew; Comber, Sean; Hutchinson, Thomas H

    2016-02-01

    Metaldehyde is a widely used molluscicide in countries where damage to crops from slugs and snails is a major problem associated with warm and wet winters. In the UK it is estimated that over 8% of the area covered by arable crops is treated with formulated granular bait pellets containing metaldehyde as the main active ingredient. Metaldehyde is hydrophilic (log Kow=0.12), water soluble (200 mg·L(-1) at 17 °C) and has been detected in UK surface waters in the concentration range of typically 0.2-0.6 μg·L(-1) (maximum 2.7 μg·L(-1)) during 2008-2011. In the absence of chronic data on potential hazards to non-target freshwater molluscs, a laboratory study was conducted to investigate the impact of metaldehyde on embryo development in the gastropod Lymnaea stagnalis (RENILYS strain) and using zinc as a positive control. L. stagnalis embryos were exposed to metaldehyde under semi-static conditions at 20±1 °C and hatching success and growth (measured as shell height and intraocular distance) examined after 21 d. Exposure concentrations were verified using HPLC and gave 21 d (hatching)NOEC and (hatching)LOEC mean measured values of 36 and 116 mg MET·L(-1), respectively (equal to the 21 d (shell height)NOEC and (shell height)LOEC values). For basic research purposes, a second group of L. stagnalis embryos was co-exposed to metaldehyde and the pesticide synergist piperonyl butoxide (PBO). Co-exposure to the PBO (measured concentrations between 0.47-0.56 mg·L(-1)) reduced hatching success from 100% to 47% and resulted in a 30% reduction in embryo growth (shell height) in snail embryos co-exposed to metaldehyde at 34-36 mg·L(-1) over 21 d. In conclusion, these data suggest mollusc embryos may have some metabolic detoxication capacity for metaldehyde and further work is warranted to explore this aspect in order to support the recent initiative to include molluscs in the OECD test guideline programme.

  10. The family Plectopylidae (Gastropoda, Pulmonata) in Laos with the description of two new genera and a new species

    PubMed Central

    Páll-Gergely, Barna; Muratov, Igor V.; Asami, Takahiro

    2016-01-01

    Abstract Previously only a single plectopylid species, Helix laomontana L. Pfeiffer, 1862 was reported from Laos. Here we erect Naggsia Páll-Gergely & Muratov, gen. n. for Helix laomontana based on the description of its reproductive anatomy and radula. Another species, Hunyadiscus saurini Páll-Gergely, gen. & sp. n. is described from Northern Laos based on conchological data. Helix (Plectopylis) andersoni Blanford, 1869, which is known from the Burmese-Chinese border region, is also classified within Hunyadiscus Páll-Gergely, gen. n. A third species, Gudeodiscus (Gudeodiscus) messageri raheemi Páll-Gergely & Hunyadi, 2015 is reported from Laos for the first time. The new localities represent the westernmost sites of the genus Gudeodiscus. The reproductive anatomy of the latter species is described. PMID:27408542

  11. Parasitic castration of Buccinanops cochlidium (Gastropoda: Nassariidae) caused by a lepocreadiid digenean in San José Gulf, Argentina.

    PubMed

    Averbuj, A; Cremonte, F

    2010-12-01

    Parasitic castration of Buccinanops cochlidium from San José Gulf, Argentina, caused by a lepocreadiid digenean, is reported for the first time. Rediae and ophtalmotrichocercous cercariae probably belonging to Opechona sp. were identified in the gonad and digestive gland. Opechona sp. has been reported previously parasitizing B. monilifer from a northern locality in the Argentine Sea. Overall prevalence of infection was 15.5%; it varied seasonally, rising during the warm months after the host oviposition period. Cercariae were expelled at the same time as the hatching of snail embryos (during the higher water temperature period). Rediae affected male and female snails equally, but prevalence increases along with host size. The parasite causes the complete castration of the host. Parasitized adult snails showed a reduction of penis size in comparison with healthy males. It remains to be confirmed whether the peak of cercariae emission coincides with the presence of jellyfishes and scombrid or other fishes in the area, which could act as second intermediate and definitive hosts, respectively. PMID:20137105

  12. A molecular phylogeny of the Littorininae (Gastropoda: Littorinidae): unequal evolutionary rates, morphological parallelism, and biogeography of the Southern Ocean.

    PubMed

    Williams, S T; Reid, D G; Littlewood, D T J

    2003-07-01

    A molecular phylogeny is presented for the subfamily Littorininae (including representatives of all subgeneric taxa and all members of a group of southern-temperate species formerly classified as 'Nodilittorina'), based on sequence data from two nuclear (18S rRNA, 28S rRNA) and two mitochondrial (12S rRNA, CO1) genes. The phylogeny shows considerable disagreement with earlier hypotheses derived from morphological data. In particular, 'Nodilittorina' is polyphyletic and is here divided into four genera (Echinolittorina, Austrolittorina, Afrolittorina new genus, and the monotypic Nodilittorina s.s.). The phylogenetic relationships of 'Littorina' striata have been controversial and it is here transferred to the genus Tectarius, a surprising relationship for which there is little morphological support. The relationships of the enigmatic Mainwaringia remain poorly resolved, but it is not a basal member of the subfamily. The two living species of Mainwaringia are remarkable for a greatly elevated rate of evolution in all four genes examined; it is suggested that this may be connected with their protandrous hermaphroditism, which is unique in the family. The molecular phylogeny provides a new framework for the adaptive radiation of the Littorininae, showing more frequent shifts between habitats and climatic regimes than previously suspected, and striking parallelism of morphological characters. The fossil record of littorinids is poor, but ages of clades are estimated using a calibration based on a Lower Eocene age of the genus Littoraria. Using these estimates, the antitropical distribution of Littorina and Afrolittorina is an ancient pattern of possibly Cretaceous age. The five members of Austrolittorina show a Gondwanan distribution in Australia, New Zealand, and South America. Based on the morphological uniformity within this clade, relatively recent (Plio-Pleistocene) trans-Pacific dispersal events seemed a likely explanation, as proposed for numerous other congeneric marine taxa. However, molecular estimation of ages of divergence suggest an initial vicariance between Australian and South American lineages at 40-73Ma, contemporary with the later stages of fragmentation of the Gondwanan supercontinent, followed by more recent (but still mid-Cenozoic) dispersal events across the Tasman Sea and the Pacific Ocean. Afrolittorina is another Cretaceous clade, now restricted to southern Africa and southern Australia, but divergence between these lineages (29-55Ma) post-dates Gondwanan fragmentation. Within both Austrolittorina and Afrolittorina all sister-species divergences are estimated to fall in the range 10-47Ma, so that there is no evidence for speciation events in the Plio-Pleistocene.

  13. Phylogeographic patterns in New Zealand and temperate Australian cantharidines (Mollusca: Gastropoda: Trochidae: Cantharidinae): Trans-Tasman divergences are ancient.

    PubMed

    Donald, Kirsten M; Spencer, Hamish G

    2016-07-01

    Current taxonomic treatments of New Zealand and temperate Australian members of the gastropod subfamily Cantharidinae imply that species on either side of the Tasman Sea are closely related and, in some cases, congeneric. Such a close relationship, however, entails a relatively recent divergence of Australian and New Zealand lineages, which seems inconsistent with what is known about cantharidine larval development in general. In order to address these issues, mitochondrial and nuclear DNA sequences were used to ascertain how cantharidine genera became established over the wide geographical range of temperate Australia and New Zealand, including their subantarctic islands. Our robust and dated phylogenies (based on 16S, COI, 12S and 28S sequences) revealed that Australian and New Zealand species fall into endemic clades that have been separated for, at most, 35million years. This divergence date postdates a vicariant split by around 50million years and we suggest that, once again, long-distance trans-Tasman dispersal has played a pivotal role in molluscan evolution in this part of the world. Our results also show that the current classification requires revision. We recognize three genera (Cantharidus [comprising 2 subgenera: Cantharidus s.str. and Pseudomargarella n. subgen.], Micrelenchus [comprising 2 subgenera: Micrelenchus s.str. and Mawhero] and Roseaplagis n. gen.) for New Zealand cantharidine species. In our dated BEAST tree, these genera form a clade with the endemic Australian Prothalotia and South African Oxystele. Other temperate Australian cantharidines in our study fall into previously recognized genera (Phasianotrochus, Thalotia, Calthalotia), which are all quite distinct from Cantharidus in spite of some authors considering various of them to be possible synonyms. Finally, we remove the Australian genus Cantharidella from the Cantharidinae to the subfamily Trochinae and erect a new genus, Cratidentium n. gen., also in the Trochinae, to accommodate several Australian species previously considered to belong to Cantharidella.

  14. Genetic structure of Onchidium "struma" (Mollusca: Gastropoda: Eupulmonata) from the coastal area of China based on mtCO I.

    PubMed

    Zhou, Na; Shen, Heding; Chen, Cheng; Sun, Bianna; Zheng, Pei; Wang, Chengnuan

    2016-01-01

    The genetic diversity and population genetic structure of Onchidium "struma" were investigated using mitochondrial cytochrome c oxidase subunit I (CO I) gene sequences. A total of 240 individuals representing 10 collection sites from across a large portion of its known range were included in the analysis. Overall, 42 haplotypes were defined and 97 polymorphic sites were observed. The O. "struma" populations had high haplotype diversity (0.9280) and nucleotide diversity (0.0404). We inferred that the early maturity and extensive survival habitat led to high genetic diversity of O. "struma" populations in China. Bayesian analysis and SAMOVA analysis showed significant genetic differentiation among populations and all populations were divided into two groups, (HK and HN) versus (GY, DF, CX, CN, ND and XM). The Mantel test revealed no significant correlation between geographic distance and genetic distance (r = 0.251; p = 0.058). Restricted gene flow caused by a shorter term pelagic veliger stage and limited dispersal potential were inferred to result in genetic differentiation among populations based on nested analysis. HK population might be an invasive species by artificial transplantation.

  15. Developmental toxicity, acute toxicity and mutagenicity testing in freshwater snails Biomphalaria glabrata (Mollusca: Gastropoda) exposed to chromium and water samples.

    PubMed

    Tallarico, Lenita de Freitas; Borrely, Sueli Ivone; Hamada, Natália; Grazeffe, Vanessa Siqueira; Ohlweiler, Fernanda Pires; Okazaki, Kayo; Granatelli, Amanda Tosatte; Pereira, Ivana Wuo; Pereira, Carlos Alberto de Bragança; Nakano, Eliana

    2014-12-01

    A protocol combining acute toxicity, developmental toxicity and mutagenicity analysis in freshwater snail Biomphalaria glabrata for application in ecotoxicological studies is described. For acute toxicity testing, LC50 and EC50 values were determined; dominant lethal mutations induction was the endpoint for mutagenicity analysis. Reference toxicant potassium dichromate (K2Cr2O7) was used to characterize B. glabrata sensitivity for toxicity and cyclophosphamide to mutagenicity testing purposes. Compared to other relevant freshwater species, B. glabrata showed high sensitivity: the lowest EC50 value was obtained with embryos at veliger stage (5.76mg/L). To assess the model applicability for environmental studies, influent and effluent water samples from a wastewater treatment plant were evaluated. Gastropod sensitivity was assessed in comparison to the standardized bioassay with Daphnia similis exposed to the same water samples. Sampling sites identified as toxic to daphnids were also detected by snails, showing a qualitatively similar sensitivity suggesting that B. glabrata is a suitable test species for freshwater monitoring. Holding procedures and protocols implemented for toxicity and developmental bioassays showed to be in compliance with international standards for intra-laboratory precision. Thereby, we are proposing this system for application in ecotoxicological studies.

  16. Limitations of cytochrome oxidase I for the barcoding of Neritidae (Mollusca: Gastropoda) as revealed by Bayesian analysis.

    PubMed

    Chee, S Y

    2015-05-25

    The mitochondrial DNA (mtDNA) cytochrome oxidase I (COI) gene has been universally and successfully utilized as a barcoding gene, mainly because it can be amplified easily, applied across a wide range of taxa, and results can be obtained cheaply and quickly. However, in rare cases, the gene can fail to distinguish between species, particularly when exposed to highly sensitive methods of data analysis, such as the Bayesian method, or when taxa have undergone introgressive hybridization, over-splitting, or incomplete lineage sorting. Such cases require the use of alternative markers, and nuclear DNA markers are commonly used. In this study, a dendrogram produced by Bayesian analysis of an mtDNA COI dataset was compared with that of a nuclear DNA ATPS-α dataset, in order to evaluate the efficiency of COI in barcoding Malaysian nerites (Neritidae). In the COI dendrogram, most of the species were in individual clusters, except for two species: Nerita chamaeleon and N. histrio. These two species were placed in the same subcluster, whereas in the ATPS-α dendrogram they were in their own subclusters. Analysis of the ATPS-α gene also placed the two genera of nerites (Nerita and Neritina) in separate clusters, whereas COI gene analysis placed both genera in the same cluster. Therefore, in the case of the Neritidae, the ATPS-α gene is a better barcoding gene than the COI gene.

  17. Standardization of a Patella spp. (Mollusca, Gastropoda) embryo-larval bioassay and advantages of its use in marine ecotoxicology.

    PubMed

    Pérez, Sara; Fernández, Nuria; Ribeiro, Pedro A

    2016-05-01

    The use of three limpet species, Patella vulgata Linnaeus, 1758, Patella depressa Pennant, 1777 and Patella ulyssiponensis Gmelin, 1791 as model organisms in marine ecotoxicology has been evaluated. Initial laboratory experiments were aimed to standardize a biological test with embryos and larvae of Patella spp, establishing the percentage of normal trochophore larvae as endpoint. Before conducting in vitro fertilization, oocytes must be maturated artificially by incubation in an alkaline solution; therefore, alkalinizing agent, pH and time of eggs alkalinization were evaluated. Moreover, time of sperm activation, optimum sperm and oocytes concentration during fertilization, gamete contact time, use of stirring during the fertilization, egg concentration and incubation temperature were examined. Minimum sample size per treatment was also estimated. Exposure of oocytes for 10min to FSW alkalinized with NH4OH at pH 9.0, the use of undiluted sperm pre-activated during 45min and a concentration of 200 oocytesmL(-1), a gamete-contact time of 180min and egg incubation at 18°C during 24h at a concentration of 80 eggsmL(-1) were the conditions allowing maximal embryo-larval development success. With an error of 0.05, a sampling size ≥320 allows a 95% confidence in the estimate. This Patella spp. acute bioassay fulfills a number of important a priori requirements to be used in ecotoxicological studies. Nevertheless, in vitro fertilization requires considerable handling, which may lead to failure in fecundation. Such difficulties are also addressed, in order to facilitate the routine use of this protocol by other laboratories.

  18. Development and validation of an OECD reproductive toxicity test guideline with the pond snail Lymnaea stagnalis (Mollusca, Gastropoda).

    PubMed

    Ducrot, Virginie; Askem, Clare; Azam, Didier; Brettschneider, Denise; Brown, Rebecca; Charles, Sandrine; Coke, Maïra; Collinet, Marc; Delignette-Muller, Marie-Laure; Forfait-Dubuc, Carole; Holbech, Henrik; Hutchinson, Thomas; Jach, Arne; Kinnberg, Karin L; Lacoste, Cédric; Le Page, Gareth; Matthiessen, Peter; Oehlmann, Jörg; Rice, Lynsey; Roberts, Edward; Ruppert, Katharina; Davis, Jessica Elphinstone; Veauvy, Clemence; Weltje, Lennart; Wortham, Ruth; Lagadic, Laurent

    2014-12-01

    The OECD test guideline development program has been extended in 2011 to establish a partial life-cycle protocol for assessing the reproductive toxicity of chemicals to several mollusk species, including the great pond snail Lymnaea stagnalis. In this paper, we summarize the standard draft protocol for a reproduction test with this species, and present inter-comparison results obtained in a 56-day prevalidation ring-test using this protocol. Seven European laboratories performed semi-static tests with cultured snails of the strain Renilys® exposed to nominal concentrations of cadmium chloride (from 53 to 608μgCdL(-1)). Cd concentrations in test solutions were analytically determined to confirm accuracy in the metal exposure concentrations in all laboratories. Physico-chemical and biological validity criteria (namely dissolved oxygen content >60% ASV, water temperature 20±1°C, control snail survival >80% and control snail fecundity >8 egg-masses per snail over the test period) were met in all laboratories which consistently demonstrated the reproductive toxicity of Cd in snails using the proposed draft protocol. Effect concentrations for fecundity after 56days were reproducible between laboratories (68

  19. Freshwater snails (Mollusca: Gastropoda) from the Commonwealth of Dominica with a discussion of their roles in the transmission of parasites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We collected six species of freshwater snails from Dominica, including Biomphalaria kuhniana, Gundlachia radiata Helisoma (= Planorbella) trivolvis, Melanoides tuberculata, Neritina punctulata, and Physa marmorata. Our collections indicate that un-reported species such as Gundlachia radiata and Hel...

  20. Checklist of the family Epitoniidae (Mollusca: Gastropoda) in Taiwan with description of a new species and some new records

    PubMed Central

    Huang, Chih-Wei; Lee, Yen-Chen

    2016-01-01

    Abstract Background The family Epitoniidae is a group of small to medium-sized gastropods and occurs globally from the intertidal zone to abyssal seabeds. There are 101 epitoniid species currently recorded from Taiwan. New information Based on our investigations of seashores and fishing ports of Taiwan, a new species and 12 new records of Epitoniidae species are reported. Of the 12 new records, four are new to the East Asian region and two are new records to the Indo-Pacific region. Our results increase the number of Taiwanese Epitoniidae from 101 species to 114 species. PMID:27660525

  1. Myogenesis in Aplysia californica (Cooper, 1863) (Mollusca, Gastropoda, Opisthobranchia) with special focus on muscular remodeling during metamorphosis.

    PubMed

    Wollesen, Tim; Wanninger, Andreas; Klussmann-Kolb, Annette

    2008-07-01

    To date only few comparative approaches tried to reconstruct the ontogeny of the musculature in invertebrates. This may be due to the difficulties involved in reconstructing three dimensionally arranged muscle systems by means of classical histological techniques combined with light or transmission electron microscopy. Within the scope of the present study we investigated the myogenesis of premetamorphic, metamorphic, and juvenile developmental stages of the anaspidean opisthobranch Aplysia californica using fluorescence F-actin-labeling in conjunction with modern confocal laser scanning microscopy. We categorized muscles with respect to their differentiation and degeneration and found three true larval muscles that differentiate during the embryonic and veliger phase and degenerate during or slightly after metamorphosis. These are the larval retractor, the accessory larval retractor, and the metapodial retractor muscle. While the pedal retractor muscle, some transversal mantle fibers and major portions of the cephalopedal musculature are continued and elaborated during juvenile and adult life, the buccal musculature and the anterior retractor muscle constitute juvenile/adult muscles which differentiate during or after metamorphosis. The metapodial retractor muscle has never been reported for any other gastropod taxon. Our findings indicate that the late veliger larva of A. californica shares some common traits with veligers of other gastropods, such as a larval retractor muscle. However, the postmetamorphic stages exhibit only few congruencies with other gastropod taxa investigated to date, which is probably due to common larval but different adult life styles within gastropods. Accordingly, this study provides further evidence for morphological plasticity in gastropod myogenesis and stresses the importance of ontogenetic approaches to understand adult conditions and life history patterns.

  2. Spatial diversity of rocky midlittoral macro-invertebrates associated with the endangered species Patella ferruginea (Mollusca: Gastropoda) of Tunisian coastline

    NASA Astrophysics Data System (ADS)

    Tlig-Zouari, Sabiha; Rabaoui, Lotfi; Fguiri, Hosni; Diawara, Moctar; Ben Hassine, Oum Kalthoum

    2010-04-01

    The present study focuses on horizontal spatial variability of benthic macrofauna associated with Patella ferruginea. Thirty-six samples collected at 12 transects belonging to 4 midlittoral sites along the rocky Tunisian coastline, were examined. A total of 44 species belonging to 5 taxa were found. Multivariate analysis applied on gathered data did not show a horizontal spatial variability at small scale (between transects), but at large scale, between sites as well as sectors. Thus, three groups of communities were identified (GI: Korbous and El Haouaria; GIIa: Zembra Island and GIIb: Kelibia). The distribution of species abundance within these groups revealed that crustaceans were the most abundant taxon, due to the overwhelming dominance of Chthamalus stellatus. This substratum appeared to create favourable micro-habitats for the installation of molluscs including gastropods. Regarding the low diversity index ( H') and evenness ( J), they seemed to reflect a disturbance and a demographic unbalance within these communities. The heterogeneity of substrate surface, created by C. stellatus specimens appeared to be caused by various complex interactions established between the key components of these communities in particular suspension feeders, predators, herbivorous molluscs and macroalgae. Thus, the dynamic status of each of these communities is the result of these complex interactions.

  3. A new species of Haplosporidium Caullery & Mesnil, 1899 in the marine false limpet Siphonaria lessonii (Gastropoda: Siphonariidae) from Patagonia.

    PubMed

    Ituarte, Cristián; Bagnato, Estefanía; Siddall, Mark; Cremonte, Florencia

    2014-05-01

    A new species of Haplosporidium Caullery & Mesnil, 1899 parasitising the pulmonate gastropod Siphonaria lessonii Blainville in Patagonia, Argentina, is described based on morphological (scanning and transmission electron microscopy) and sequence (small subunit ribosomal RNA gene) data. Different stages of sporulation were observed as infections disseminated in the digestive gland. Haplosporidium patagon n. sp. is characterised by oval or slightly subquadrate spores with an operculum that is ornamented with numerous short digitiform projections of regular height, perpendicular to and covering its outer surface. The operculum diameter is slightly larger than the apical diameter of the spore. Neither the immature nor mature spores showed any kind of projections of the exosporoplasm or of the spore wall. Regarding phylogenetic affinities, the new species was recovered as sister to an undescribed species of Haplosporidium Caullery & Mesnil, 1899 from the polychaete family Syllidae Grube from Japanese waters. The morphological characters (ornamentation of the operculum, spore wall structure, shape and size of spores, and the lack of spore wall projections) corroborate it as an as yet undescribed species of Haplosporidium and the first for the phylum in marine gastropods of South America. Siphonaria lessonii is the only known host to date.

  4. A review of the microgastropod genus Systenostoma Bavay & Dautzenberg, 1908 and a new subterranean species from China (Gastropoda, Pulmonata, Hypselostomatidae)

    PubMed Central

    Jochum, Adrienne; Slapnik, Rajko; Kampschulte, Marian; Martels, Gunhild; Heneka, Markus; Páll-Gergely, Barna

    2014-01-01

    Abstract A review of the microgastropod genus Systenostoma is provided. Thai and Malaysian species are transferred to a new genus, Angustopila (type species: Systenostoma tamlod Panha & Burch, 1999). A new subterranean Angustopila species is described here. Conchologically, the new species is most similar to the cave-dwelling, Thai A. tamlod (Panha & Burch, 1999). One Thai species (Systenostoma edentata) is transferred to the genus Hypselostoma. Vietnamese members remain in the genus Tonkinospira (nomen novum) for Systenostoma Bavay & Dautzenberg, 1908 (non Systenostoma Marsson, 1887). A comprehensive map of former Systenostoma species is presented. SEM and NanoCT images, including a video of A. huoyani sp. n. internal shell morphology, provide novel perspectives of the shells of Angustopila and of the scarcely known Vietnamese Tonkinospira species. The biology of these snails is not yet known but collection localities suggest a troglophilic ecology. PMID:24899848

  5. Seasonal Variations in Maternal Provisioning of Crepidula fornicata (Gastropoda): Fatty Acid Composition of Females, Embryos and Larvae

    PubMed Central

    Leroy, Fanny; Meziane, Tarik; Riera, Pascal; Comtet, Thierry

    2013-01-01

    Recruitment success of marine invertebrate populations not only depends on the number of recruits but also on their quality which affects their survival. In species characterized by a mixed development (encapsulated embryonic development and release of planktotrophic larvae), the offspring quality depends on both maternal provisioning and larval feeding. Here, we investigated potential changes of maternal provisioning over the whole reproductive period in a gastropod with a mixed development: Crepidulafornicata. In its introduction area, C. fornicata reproduces from February to October, which implies that both adults and larvae are exposed to different food availabilities. Maternal provisioning was assessed by measuring the fatty acid (FA) composition of females, encapsulated embryos and larvae, in February, May, July and September 2009. FA are essential resources for the development of embryos and larvae, and are key biomarkers of offspring quality. Our results showed differences in FA composition between muscles, visceral masses, and encapsulated embryos. In particular, FA composition of embryos was similar to that of the visceral mass. Seasonal variations in FA composition were observed: in the middle of the reproductive season (May and July), female tissues and embryos showed a higher proportion of polyunsaturated fatty acids and especially ω3, as compared to the beginning and end of the reproductive season (February and September). This showed that through maternal provisioning the quality of C. fornicata offspring was higher in the middle of the reproductive season. Whether this would result in an increase of recruitment success and juvenile performance would require further investigations. PMID:24086505

  6. The complete mitochondrial genome of Haliotis laevigata (Gastropoda: Haliotidae) using MiSeq and HiSeq sequencing.

    PubMed

    Robinson, Nick A; Hall, Nathan E; Ross, Elizabeth M; Cooke, Ira R; Shiel, Brett P; Robinson, Andrew J; Strugnell, Jan M

    2016-01-01

    The mitochondrial genome of greenlip abalone, Haliotis laevigata, is reported. MiSeq and HiSeq sequencing of one individual was assembled to yield a single 16,545 bp contig. The sequence shares 92% identity to the H. rubra mitochondrial genome (a closely related species that hybridize with H. laevigata in the wild). The sequence will be useful for determining the maternal contribution to hybrid populations, for investigating population structure and stock-enhancement effectiveness.

  7. Cryptic Species in Tropic Sands - Interactive 3D Anatomy, Molecular Phylogeny and Evolution of Meiofaunal Pseudunelidae (Gastropoda, Acochlidia)

    PubMed Central

    Neusser, Timea P.; Jörger, Katharina M.; Schrödl, Michael

    2011-01-01

    Background Towards realistic estimations of the diversity of marine animals, tiny meiofaunal species usually are underrepresented. Since the biological species concept is hardly applicable on exotic and elusive animals, it is even more important to apply a morphospecies concept on the best level of information possible, using accurate and efficient methodology such as 3D modelling from histological sections. Molecular approaches such as sequence analyses may reveal further, cryptic species. This is the first case study on meiofaunal gastropods to test diversity estimations from traditional taxonomy against results from modern microanatomical methodology and molecular systematics. Results The examined meiofaunal Pseudunela specimens from several Indo-Pacific islands cannot be distinguished by external features. Their 3D microanatomy shows differences in the organ systems and allows for taxonomic separation in some cases. Additional molecular analyses based on partial mitochondrial cytochrome c oxidase subunit I (COI) and 16S rRNA markers revealed considerable genetic structure that is largely congruent with anatomical or geographical patterns. Two new species (Pseudunela viatoris and P. marteli spp. nov.) are formally described integrating morphological and genetic analyses. Phylogenetic analysis using partial 16S rRNA, COI and the nuclear 18S rRNA markers shows a clade of Pseudunelidae species as the sister group to limnic Acochlidiidae. Within Pseudunela, two subtypes of complex excretory systems occur. A complex kidney already evolved in the ancestor of Hedylopsacea. Several habitat shifts occurred during hedylopsacean evolution. Conclusions Cryptic species occur in tropical meiofaunal Pseudunela gastropods, and likely in other meiofaunal groups with poor dispersal abilities, boosting current diversity estimations. Only a combined 3D microanatomical and molecular approach revealed actual species diversity within Pseudunela reliably. Such integrative methods are recommended for all taxonomic approaches and biodiversity surveys on soft-bodied and small-sized invertebrates. With increasing taxon sampling and details studied, the evolution of acochlidian panpulmonates is even more complex than expected. PMID:21912592

  8. Surviving the Messinian Salinity Crisis? Divergence patterns in the genus Dendropoma (Gastropoda: Vermetidae) in the Mediterranean Sea.

    PubMed

    Calvo, Marta; Alda, Fernando; Oliverio, Marco; Templado, José; Machordom, Annie

    2015-10-01

    Four genetically distinct clades were recently described under the name Dendropoma petraeum, a Mediterranean endemic vermetid gastropod. The aim of this work is to date the processes that drove to the diversification within this taxon and to relate them to the corresponding historical events occurred in the Mediterranean Sea. Sequences from mitochondrial and nuclear markers were obtained from specimens collected in 29 localities spanning over 4000km across the entire distribution range of D. petraeum species complex. The phylogenetic and coalescent-based analyses confirmed the four well-supported and largely differentiated lineages of D. petraeum, clearly delimited geographically along a west-east axis within the Mediterranean Sea: Western, Tyrrhenian-Sicilian, Ionian-Aegean and Levantine lineages. Divergence time estimates, obtained using a range of known substitution rates for other marine gastropods, indicated two main stages of diversification. In the first period (between 9.5 and 4.5mya), the ancestral D. petraeum diverged into the current four lineages. The most recent period occurred between 3.72 and 0.66mya in the late Pliocene-early Pleistocene, and included the main within-lineage diversification events. Therefore, if the divergence time between the major lineages of Dendropoma in the Mediterranean actually predated or coincided with the Messinian Salinity Crisis, then they should have survived to this dramatic period within the Mediterranean, as supported by Bayes Factors model comparison. Conversely, if the divergence started after the crisis, congruent with the idea that no true marine organism survived the Messinian Salinity Crisis, then our results indicate substitution rates of Dendropoma much higher than usual (5.16% per million years for COI, 3.04% for 16S). More recent climate changes seem to have conditioned the demographic history of each lineage differently. While Western and Tyrrhenian-Sicilian lineages both underwent an increase in their effective population sizes from 1.5 to 0.6mya coinciding with a long interglacial period, the Ionian-Aegean and Levantine lineages showed constant effective population sizes since 2-2.5mya, suggesting that these eastern lineages might represent small and relict populations surviving the subsequent Quaternary glaciations in isolated refugia. PMID:26002830

  9. Description and evaluation of imposex in Strombus canarium Linnaeus, 1758 (Gastropoda, Strombidae): a potential bio-indicator of tributyltin pollution.

    PubMed

    Cob, Zaidi Che; Arshad, Aziz; Bujang, Japar Sidik; Abd Ghaffar, Mazlan

    2011-07-01

    Strombus canarium Linnaeus, 1758 is an important gastropod species within the study area and was traditionally collected for food by the locals. The objective of the present study is to assess the incidence of imposex and its severity in this species. Adult conchs were sampled during their main reproductive period, from October 2005 to January 2006, at Sungai Pulai estuary, Johor Straits, Malaysia. A total of 32.81% of adult females showed imposex characteristics, with varying degrees of severity though. The relative penis size (RPS) index ranged from 1.74 to 33.29 (mean = 13.40 ± 2.27, n = 21), while the relative penis length (RPL) index ranged from 6.28 to 55.19 (mean = 25.83 ± 3.33, n = 21). The use of vas deferens sequence (VDS) index was however cannot be applied as the presence of egg groove obscured any vas deferens development in affected females. Sequence of imposex (male penis) development in female conch, from merely a small stump to an advance male penis homologous was therefore carefully analyzed and described, and an alternative imposex classification scheme was proposed. S. canarium can be a good indicator for monitoring of organotin pollution within the study area. However, more studies are needed in order to further develop and test its validity and application, such as its correlation with levels of pollutant within the tissues and the environment, as well as its application on other Strombus species. PMID:20824325

  10. [Genetic diversity in two populations of the snail Strombus gigas (Gastropoda: Strombidae) from Yucatan, Mexico, using microsatellite].

    PubMed

    Zamora-Bustillos, Roberto; Rodríguez-Canul, Rossanna; García de León, Francisco J; Tello Cetina, Jorge

    2011-09-01

    The pink conch Strombus gigas is an important fisheries resource in the Caribbean region, including the Yucatán Peninsula. We analyzed the genetic diversity and genetic structure of two populations (Alacranes Reef and Chinchorro Bank) with the use of five microsatellite molecular markers. The results indicate that the two populations are in the same rank of genetic diversity (He), from 0.613 to 0.692. Significant deviation from H-WE was observed in the both populations due to deficit to heterozygotes, this was attributed to inbreeding as a consequence of over-fishing; nevertheless, other possible causes considered are mixing of individuals from two or more populations, and the existence of null alleles. Levels of genetic differentiation indicated the existence of a single homogenous population in the Yucatan Peninsula (F(ST) de 0.003, p = 0.49), which fits with highest levels of gene flow is significant (2.3 individuals) between both populations. Results from this study support the hypothesis that S. gigas is part of a single panmictic population in the Yucatan Peninsula; therefore, this fishery resource should be regulated the same way for both areas. PMID:22017119

  11. Revision of Partulidae (Gastropoda, Stylommatophora) of Palau, with description of a new genus for an unusual ground-dwelling species

    PubMed Central

    Slapcinsky, John; Kraus, Fred

    2016-01-01

    Abstract We describe a new stylommatophoran land snail of the family Partulidae from Palau. The new species has a combination of morphological and ecological characters that do not allow its placement in any existing partulid genus, so we describe a new genus for it. The new genus is characterized by a large (18–23 mm) obese-pupoid shell; smooth protoconch; teleoconch with weak and inconsistent, progressively stronger, striae; last half of body whorl not extending beyond the penultimate whorl; widely expanded and reflexed peristome; relatively long penis, with longitudinal pilasters that fuse apically into a fleshy ridge that divides the main chamber from a small apical chamber; and vas deferens entering and penial-retractor muscle attaching at the apex of the penis. Unlike all other partulids, the new species is strictly associated with rocks in contact with the ground. Comparing the other three Palauan species – currently assigned to Partula – to our new genus and to other partulids makes it clear that they require their own genus because their morphology is quite different from that of true Partula and from that of all other genera. Hence, we resurrect the name Palaopartula Pilsbry for these snails. PMID:27667931

  12. Revision of Partulidae (Gastropoda, Stylommatophora) of Palau, with description of a new genus for an unusual ground-dwelling species

    PubMed Central

    Slapcinsky, John; Kraus, Fred

    2016-01-01

    Abstract We describe a new stylommatophoran land snail of the family Partulidae from Palau. The new species has a combination of morphological and ecological characters that do not allow its placement in any existing partulid genus, so we describe a new genus for it. The new genus is characterized by a large (18–23 mm) obese-pupoid shell; smooth protoconch; teleoconch with weak and inconsistent, progressively stronger, striae; last half of body whorl not extending beyond the penultimate whorl; widely expanded and reflexed peristome; relatively long penis, with longitudinal pilasters that fuse apically into a fleshy ridge that divides the main chamber from a small apical chamber; and vas deferens entering and penial-retractor muscle attaching at the apex of the penis. Unlike all other partulids, the new species is strictly associated with rocks in contact with the ground. Comparing the other three Palauan species – currently assigned to Partula – to our new genus and to other partulids makes it clear that they require their own genus because their morphology is quite different from that of true Partula and from that of all other genera. Hence, we resurrect the name Palaopartula Pilsbry for these snails.

  13. Polycyclic aromatic hydrocarbons in Haliotis tuberculata (Linnaeus, 1758) (Mollusca, Gastropoda): Considerations on food safety and source investigation.

    PubMed

    Conte, Francesca; Copat, Chiara; Longo, Sabrina; Conti, Gea Oliveri; Grasso, Alfina; Arena, Giovanni; Dimartino, Angela; Brundo, Maria Violetta; Ferrante, Margherita

    2016-08-01

    Polycyclic aromatic hydrocarbons were analyzed in wild specimens of Haliotis tuberculata from three sites of the Sothern Ionian Sea. The species Ht is commonly found at these sites and has significant commercial value. Main results revealed mean values of benzo(a)pyrene higher than the threshold set by Regulation No. 835/2011/EU in all sampling sites and the sum of selected PAHs, expressed as ΣPAH4 by EC Regulation, were below the limit set by the same Regulation in ME and VSG. We found generally higher concentrations than literature finding, especially for low molecular weight PAHs, and results of diagnostic ratios highlighted both pyrolytic and petrogenic sources. The potential human health risks due consumption of Ht by local inhabitants have been assessed by exposure daily intake (EDI), target hazard quotient (THQ) and lifetime cancer risk (CR). EDI values were below the intake range reviewed by EFSA for each class of contaminant. BaP daily intake was below the value of 10 ng/Kg/day, suggested by JFCFA, and CRBaP was slightly higher than the acceptable risk level (ARL) of 1×10(-5). Conversely, target hazard quotient (THQ) resulted always below 1, thus the risk to develop chronic systemic effects due naphthalene, acenaphthene, fluorene, anthracene, fluoranthene and pyrene was low.

  14. The genus Pirenella Gray, 1847 (= Cerithideopsilla Thiele, 1929) (Gastropoda: Potamididae) in the Indo-West Pacific region and Mediterranean Sea.

    PubMed

    Reid, David G; Ozawa, Tomowo

    2016-01-01

    Members of the genus Pirenella are abundant inhabitants of intertidal sedimentary shores, often found in association with mangroves, on the continental margins of the western Pacific and Indian Oceans, and eastern Mediterranean Sea. Until recently, four morphological species were recognised in the tropical Indo-West Pacific region and classified in the genus Cerithideopsilla, while another species occupying the Mediterranean and Indian Ocean was classified as Pirenella conica. Molecular phylogenetic analysis has demonstrated that all these species are congeneric and here it is shown that the valid name for the genus is Pirenella. A recently published molecular study recognised a total of 16 species and the present work is a systematic account of these species. Of the 16, nine are described as new. Other significant nomenclatural acts are: fixation of type species of Pirenella as Pirenella mammillata J.E. Gray, 1847; designation of neotypes for Cerithium alatum Philippi, 1849, Cerithium microptera Kiener, 1841, Cerithium conicum Blainville, 1829, Pirenella mammillata J.E. Gray, 1847 and Murex cingulatus Gmelin, 1791; designation of lectotype for Cerithium retiferum G.B. Sowerby II, 1855. The species accounts include full synonymies, detailed descriptions of shells (based on 831 museum samples), distribution records and maps, reviews of life history, of habitat and of ecology, and some images of radulae. Details of shell sculpture are adequate for the diagnosis of most species. Distorted shells are common in some populations and are suggested to represent parasitised individuals. Some species are pests of fishponds in Southeast Asia and P. conica is the intermediate host of a trematode responsible for the human disease heterophyiasis, while others are threatened by habitat destruction. PMID:27395955

  15. Annotated type catalogue of Bothriembryon (Mollusca, Gastropoda, Orthalicoidea) in Australian museums, with a compilation of types in other museums.

    PubMed

    Breure, Abraham S H; Whisson, Corey S

    2012-01-01

    Type material of 41 Australian Bothriembryon taxa present in Australian museums is critically listed, indicating systematic issues that need to be resolved in further studies. Information on additional type material of 22 taxa in non-Australian museums is compiled. The seven fossil taxa known so far are included in this catalogue. Based on the current systematic position, 38 species are treated in this paper. Bothriembryon jacksoni Iredale, 1939, Bothriembryon notatus Iredale, 1939, Bothriembryon praecelsus Iredale, 1939 and Bothriembryon serpentinus Iredale, 1939 are elevated to species level. Bothriembryon gratwicki (Cox, 1899) is listed as status to be determined.

  16. Rapana thomasiana grosse (gastropoda) haemocyanin: spectroscopic studies of the structure in solution and the conformational stability of the native protein and its structural subunits.

    PubMed

    Dolashka, P; Genov, N; Parvanova, K; Voelter, W; Geiger, M; Stoeva, S

    1996-04-01

    1. The stability towards pH changes, thermal and chemical (guanidine hydrochloride) denaturation of the oxy- and apo-forms of the native Rapana thomasiana haemocyanin and its structural subunits, RHSS1 and RHSS2, has been investigated using fluorescence and CD spectroscopy. The association of the subunits into haemocyanin aggregates increases considerably the melting temperature and the free energy of stabilization in water. The guanidine hydrochloride denaturation of the aggregated oxygen-transporting protein depends slightly on the protein concentration. The denaturation of the individual subunits is concentration-independent. Rapana haemocyanin is 5.9-7.5 kJ/mol more stable than the constituent polypeptide chains. 2. Upon excitation of the native haemocyanin and the subunits at 295 or 280 nm the fluorescence emission is determined by tryptophyl residues 'buried' deeply in the hydrophobic interior of the protein globules. This is confirmed by quenching experiments with acrylamide, caesium and iodide ions. The efficiency of the radiationless energy transfer between the phenol (donor) and indole (acceptor) fluorophores in the three species, native haemocyanin, RHSS1 and RHSS2, has been determined. An efficient 'interchain' energy transfer between tyrosyl and tryptophyl residues from different polypeptide chains occurs in the non-dissociated form of the haemocyanin. 3. The tryptophan emission of the oxyhaemocyanin, oxy-RHSS1 and oxy-RHSS 2 is strongly quenched by the copper-dioxygen complex at the active site and the respective quantum yields of fluorescence of the oxygenated species are 4-7 times lower than those of the apo-forms. Protonated imidazole groups quench the fluorescence of neighbouring exited indole rings, probably by charge-transfer complex formation. PMID:8670098

  17. Calyptraeotheres sp. nov. (Crustacea: Decapoda: Pinnotheridae), symbiont of the slipper shell Crepidula striolata Menke, 1851 (Mollusca: Gastropoda: Calyptraeidae) from the Gulf of California, Mexico.

    PubMed

    Ayón-Parente, Manuel; Hendrickx, Michel E

    2014-01-01

    Calyptraeotheres camposi sp. nov. is described from the Gulf of California, Mexico. The new species is close to C. granti (Glassell, 1933) and C. pepeluisi Campos & Hernández-Ávila, 2010 from the Mexican Pacific and to C. hernandezi Hernández-Ávila & Campos 2006 from the Western Atlantic. These four species feature a third maxilliped with a 2-segmented endopod palp and the exopod with unsegmented flagellum. Calyptraeotheres camposi sp. nov. differs from C. granti and C. hernandezi by having the eyes visible in dorsal view, the carapace with arcuate anterolateral margins, the dorsal, longitudinal depressions connected with the transversal depression, and the propodus of pereiopod 2 equal or slightly longer than the carpus. From C. pepeluisi it is distinguished by the absence of a transversal depression on the carapace and the longitudinal depressions not connecting, the carpus and propodus of the third maxilliped being sub-trapezoidal and sub-conical, respectively, in lieu of subrectangular, and the inner surface of the fixed finger nude instead of bearing short setae near the cutting edge and ventral margin. PMID:25544074

  18. Description of two new species of Rissoella Gray, 1847 (Mollusca, Gastropoda, Heterobranchia) from Venezuela, with a key to the Caribbean species known for the genus.

    PubMed

    Caballer, Manuel; Ortea, Jesus; Narciso, Samuel

    2011-01-01

    Two new species of the genus Rissoella Gray, 1847 are described from Venezuela, one from the National Park Morrocoy, Rissoella morrocoyensissp. n. and the other from the Wildlife Refuge Isla de Aves, Rissoella venezolanicolasp. n.Rissoella morrocoyensissp. n. has a deep umbilicus (partly closed), preumbilical cord, black head, hypobranchial gland marked by a pale yellow boomerang-shaped ribbon and it lives on the leaves of the seagrass Thalassia testudinum Banks & König, 1805. Rissoella venezolanicolasp. n. has an angled preumbilical cord which extends to the columella delimiting a trapezoid, a hypobranchial gland marked by a yellow quaver-shaped ribbon and protoconch with fuchsia highlights. It lives on the brown alga Dictyota spp. The records of Rissoella in the Caribbean are revised and illustrations, a comparative table and a key to the Caribbean species known for the genus are provided. PMID:21976997

  19. Glowing seashells: diversity of fossilized coloration patterns on coral reef-associated cone snail (Gastropoda: Conidae) shells from the Neogene of the Dominican Republic.

    PubMed

    Hendricks, Jonathan R

    2015-01-01

    The biology of modern Conidae (cone snails)--which includes the hyperdiverse genus Conus--has been intensively studied, but the fossil record of the clade remains poorly understood, particularly within an evolutionary framework. Here, ultraviolet light is used to reveal and characterize the original shell coloration patterns of 28 species of cone snails from three Neogene coral reef-associated deposits from the Cibao Valley, northern Dominican Republic. These fossils come from the upper Miocene Cercado Fm. and lower Pliocene Gurabo Fm., and range in age from about 6.6-4.8 Ma. Comparison of the revealed coloration patterns with those of extant species allow the taxa to be assigned to three genera of cone snails (Profundiconus, Conasprella, and Conus) and at least nine subgenera. Thirteen members of these phylogenetically diverse reef faunas are described as new species. These include: Profundiconus? hennigi, Conasprella (Ximeniconus) ageri, Conus anningae, Conus lyelli, Conus (Atlanticonus?) franklinae, Conus (Stephanoconus) gouldi, Conus (Stephanoconus) bellacoensis, Conus (Ductoconus) cashi, Conus (Dauciconus) garrisoni, Conus (Dauciconus?) zambaensis, Conus (Spuriconus?) kaesleri, Conus (Spuriconus?) lombardii, and Conus (Lautoconus?) carlottae. Each of the three reef deposits contain a minimum of 14-16 cone snail species, levels of diversity that are similar to modern Indo-Pacific reef systems. Finally, most of the 28 species can be assigned to modern clades and thus have important implications for understanding the biogeographic and temporal histories of these clades in tropical America.

  20. Digyalum oweni, gen. nov., sp. nov., a new and unusual gregarin protozoan from the gut of mollusc Littorina obtusata (Prosobranchia: Gastropoda).

    PubMed

    Koura, E A; Grahame, J; Owen, R W; Kamel, E G

    1990-06-01

    Digyalum oweni, gen. nov., sp. nov., is described from the gut of the gastropod mollusc Littorina obtusata. The gregarine has the unusual features of transverse orientation of the epicyte folds and two anterior pouch-like hollows. PMID:2110230

  1. On the identities of the molluscan names described in A Short Zoology of Tahiti in the Society Islands by Anthony Curtiss in 1938 (Mollusca: Cephalopoda, Gastropoda).

    PubMed

    Low, Martyn E Y; Tan, Siong Kiat

    2014-02-11

    Anthony Curtiss described two species of cephalopod and nine species of gastropod molluscs from Tahiti. Herein, we discuss and determine the identities of these eleven names. Ten of these names are considered to be junior subjective synonyms of well-known taxa, and one an unavailable name.

  2. A new species of Aeneator Finlay, 1926 (Mollusca, Gastropoda, Buccinidae) from northern Chile, with comments on the genus and a key to the Chilean species

    PubMed Central

    Araya, Juan Francisco

    2013-01-01

    Abstract A new species of the genus Aeneator Finlay, 1926 is described from off the coast of Caldera (27°S), northern Chile. Aeneator martae sp. n. has a small, broad, stout, angulated shell with more prominent axial ribs and a more obviously keeled periphery than all previously named Chilean species. Comparisons are provided with all other South American named species of Aeneator. PMID:23653495

  3. Use of isozyme patterns in the identification of Biomphalaria tenagophila (D'Orbigny, 1835) and B. occidentalis (Paraense, 1981) (Gastropoda: Planorbidae).

    PubMed

    Mascara, D; Morgante, J S

    1995-01-01

    Two sibling species of Biomphalaria, B. tenagophila and B. occidentalis were identified using isozyme patterns obtained by horizontal gel electrophoresis. Six diagnostic enzymatic loci were identified in digestive gland homogenates. The results enable us to distinguish the species, calculate the Nei's coefficient of genetic similarity, and provide a basis for making inferences about the pattern of these two planorbid species colonization and distribution.

  4. Description of two new Ecuadorian Zilchistrophia Weyrauch, 1960, with the clarification of the systematic position of the genus based on anatomical data (Gastropoda, Stylommatophora, Scolodontidae)

    PubMed Central

    Páll-Gergely, Barna; Asami, Takahiro

    2014-01-01

    Abstract Two new species of the genus Zilchistrophia Weyrauch, 1960 are described from Eastern Ecuadorian rain forest: Zilchistrophia hilaryae sp. n. and Zilchistrophia shiwiarorum sp. n. These two new species extend the distribution of the genus considerably northwards, because congeners have been reported from Peru only. For the first time we present anatomical data (radula, buccal mass, morphology of the foot and the genital structure) of Zilchistrophia species. According to these, the genus belongs to the family Scolodontidae, subfamily Scolodontinae (=“Systrophiini”). The previously assumed systematic relationship of Zilchistrophia with the Asian Corillidae and Plectopylidae based on the similarly looking palatal plicae is not supported. PMID:25493057

  5. Sub-seasonal oxygen and carbon isotope variations in shells of modern Radix sp. (Gastropoda) from the Tibetan Plateau: potential of a new archive for palaeoclimatic studies

    NASA Astrophysics Data System (ADS)

    Taft, Linda; Wiechert, Uwe; Riedel, Frank; Weynell, Marc; Zhang, Hucai

    2012-02-01

    Carbon and oxygen isotope ratios have been measured for nine aragonite shells of the gastropod genus Radix from the lake Bangda Co (30°29'N, 97°04'E, 4450 m a.s.l.) at the south-eastern edge and from two characteristic sites at the lake Kyaring Co (31°09'N, 88°17'E, 4650 m a.s.l.) on the central Tibetan Plateau. Radix shells were sampled for isotope ratio analysis with high spatial resolution along the ontogenetic spiral of growth providing the basis of isotope records with a sub-seasonal time-resolution. δ18O values of shells from Bangda Co are on average ˜-15.0‰ relative to PDB and the pattern exhibits a clear onset and progression of the summer monsoon precipitation indicated by a strong "amount effect". This pattern mirrors the precipitation pattern in the respective year and region as expected for a small (surface area ca 0.3 km2) and shallow (<5 m) lake or habitat with short water residence times and little evaporative 18O enrichment of the lake water. In contrast, δ18O values of Radix shells from Kyaring Co habitat A which is connected to the deep (several tens of metres) and big (surface area ca 660 km2) lake, average at ˜-13.0‰ consistent with a higher evaporation rate and longer water residence time. The latter is supported by more 18O enriched water in this habitat. The δ18O values of Radix shells from Kyaring Co habitat B are nearly as low as shells from Bangda Co due to the similar habitat characteristic but isotopic patterns of these shells exhibit a weaker "amount effect". In both lake systems δ13C values of the shells are coupled with oxygen isotopes because a large amount of isotopically light carbon is washed from mountain slopes into the lake during the rainy season. Although other processes influence the isotopic patterns, e.g. biological productivity (δ13C) or temperature (δ18O), these influences are minor compared with the monsoon signal or the effect of evaporation in the Radix shell records. The overall weaker amount effect in Radix shells from Kyaring Co habitat B compared with shells from Bangda Co are consistent with a current decreasing monsoon influence from the south-eastern edge towards the central Tibetan Plateau. Thus, fossil shells of the gastropod genus Radix are a valuable archive for reconstructing climatic and environmental changes on the Tibetan Plateau and provide information about former habitat sizes and depths.

  6. Three new species of Ammonicera from the Eastern Pacific coast of North America, with redescriptions and comments on other species of Omalogyridae (Gastropoda, Heterobranchia).

    PubMed

    Sartori, André F; Bieler, Rüdiger

    2014-01-01

    The family Omalogyridae comprises some of the smallest known marine snails. Like all micromolluscs, they have been historically neglected and are underrepresented in faunistic surveys. Based on a few focused studies of the family, 15 valid omalogyrid species were previously recognised in the Indian and Pacific Oceans. To these, we add 3 new species based on a morphological analysis of material in the dry collection of the Natural History Museum of Los Angeles County, applying light and scanning electron microscopies. The new species, Ammonicera mcleani, A. mexicana and A. sleursi, are the first omalogyrid species described from the Eastern Pacific coast of North America. Redescriptions of the Australian omalogyrids Ammonicera sucina (Laseron, 1954) and Omalogyra liliputia (Laseron, 1954) are also presented, detailing for the first time ultrastructural aspects of their shell morphology. Additionally, we present here the first record of Ammonicera binodosa Sleurs, 1985b in Sri Lanka, introduce the new combination Ammonicera vangoethemi (Sleurs, 1985c) for Omalogyra vangoethemi, and formally remove Transomalogyra Palazzi & Gaglini, 1979 from Omalogyridae by fixing its type species as Homalogyra densicostata Jeffreys, 1884. Finally, we present lists, geographic records and a bibliography of all currently recognised omalogyrid species in the Indian, Pacific and Antarctic Oceans, as well as an update to a previously published compilation of the Atlantic and Mediterranean representatives of the family. PMID:25544067

  7. Evaluation of the mitochondrial system in the gonad-digestive gland complex of Biomphalaria glabrata (Mollusca, Gastropoda) after infection by Echinostoma paraensei (Trematoda, Echinostomatidae).

    PubMed

    Tunholi, Victor Menezes; Tunholi-Alves, Vinícius Menezes; Santos, Anderson Teixeira; Garcia, Juberlan da Silva; Maldonado, Arnaldo; da-Silva, Wagner Seixas; Rodrigues, Maria de Lurdes de Azevedo; Pinheiro, Jairo

    2016-05-01

    The effect of infection by Echinostoma paraensei on the mitochondrial physiology of Biomphalaria glabrata was investigated after exposure to 50 miracidia. The snails were dissected one, two, three and four weeks after infection for collection and mechanical permeabilization of the gonad-digestive gland (DGG) complex. The results obtained indicate that prepatent infection by this echinostomatid fluke significantly suppresses the phosphorylation state (respiratory state 3) and basal oxygen consumption of B. glabrata, demonstrating that the infection reduces the ability of the intermediate host to carry out aerobic oxidative reactions. Additionally, relevant variations related to the uncoupled mitochondrial (state 3u) of B. glabrata infected by E. paraensei were observed. Four weeks after exposure, a significant reduction in mitochondrial oxygen consumption after addition of ADP (3.68±0.26pmol O2/mg proteins) was observed in the infected snails in comparison with the respective control group (5.14±0.25). In the uncoupled state, the infected snails consumed about 62% less oxygen than the infected snails (7.87±0.84pmol O2/mg proteins) in the same period. These results demonstrate a reduction in oxidative decarboxylation rate of the tricarboxylic acid cycle and faster anaerobic degradation of carbohydrates in the infected snails. The possible mechanisms that explain this new metabolic condition in the infected organisms are discussed. PMID:27079167

  8. Changes in chemical components in the freshwater apple snail, Pomacea canaliculata (Gastropoda: Ampullariidae), in relation to the development of its cold hardiness.

    PubMed

    Matsukura, Keiichiro; Tsumuki, Hisaaki; Izumi, Yohei; Wada, Takashi

    2008-04-01

    The apple snail, Pomacea canaliculata, is an invasive freshwater snail. It increases its cold hardiness before winter. However, the physiological mechanism of cold hardiness in molluscs is poorly understood, especially in freshwater molluscs. In this study, we examined the changes in low molecular weight compounds, glycogen and lipids, in the body of P. canaliculata in association with the development of cold hardiness. When snails without cold hardiness were experimentally cold-acclimated, the amount of glycerol, glutamine, and carnosine increased, while glycogen and phenylalanine decreased. Overwintering cold-tolerant snails collected from a drained paddy field in November also showed increased glycerol in their bodies with decreasing glycogen concentration, compared to summer snails collected from a submerged field. Water content also decreased during the cold acclimation, although the water loss was minimal. These results indicate that the freshwater snail, P. canaliculata enhances cold hardiness by accumulation of some kinds of low molecular weight compounds in its body as some insects do. However, the actual function of each low molecular compound is still unknown.

  9. The influence of diet on comparative trace metal cadmium, copper and zinc accumulation in Thais clavigera (Gastropoda: Muricidae) preying on intertidal barnacles or mussels.

    PubMed

    Blackmore, Graham; Morton, Brian

    2002-09-01

    The influence of diet on comparative metal accumulation was investigated using a predatory muricid gastropod Thais clavigera. Individuals were fed for up to 56 days on either barnacles, i.e., Tetraclita squamosa, or mussels, i.e., Perna viridis, collected from metal-contaminated and clean sites. Barnacles and mussels have contrasting metal handling strategies and, therefore, different body concentrations, intracellular distributions and detoxification systems. Field collection of prey items that accumulated body metal concentrations over a lifetime of exposure allowed bioavailability to the predator, T. clavigera, to be assessed naturally, which may not be the case for prey exposed to metals for a short time in the laboratory. T. clavigera that was fed cadmium- and copper-contaminated barnacles or mussels ingested significantly greater amounts compared to those fed conspecifics collected from clean locations. T. clavigera body cadmium and copper concentrations were not, however, significantly different between individuals fed either contaminated or clean prey. Amount of zinc ingested was similar in mussels collected from clean and contaminated environments but much less when compared to the barnacle prey. The body concentrations of zinc in T. clavigera fed mussels collected from both sites fell. In contrast, the amount of zinc ingested from barnacle prey was significantly greater from those collected from the metal-contaminated site as compared to the clean one. This was reflected as significantly greater body zinc concentrations in T. clavigera fed contaminated barnacles compared to those fed clean individuals. Copper and zinc accumulation from prey was, therefore, complex. It varied between metal and between prey type, but appeared to be related to the amount ingested and the metal handling strategy of the prey.

  10. Identification and qualification of 500 nuclear, single-copy, orthologous genes for the Eupulmonata (Gastropoda) using transcriptome sequencing and exon capture.

    PubMed

    Teasdale, Luisa C; Köhler, Frank; Murray, Kevin D; O'Hara, Tim; Moussalli, Adnan

    2016-09-01

    The qualification of orthology is a significant challenge when developing large, multiloci phylogenetic data sets from assembled transcripts. Transcriptome assemblies have various attributes, such as fragmentation, frameshifts and mis-indexing, which pose problems to automated methods of orthology assessment. Here, we identify a set of orthologous single-copy genes from transcriptome assemblies for the land snails and slugs (Eupulmonata) using a thorough approach to orthology determination involving manual alignment curation, gene tree assessment and sequencing from genomic DNA. We qualified the orthology of 500 nuclear, protein-coding genes from the transcriptome assemblies of 21 eupulmonate species to produce the most complete phylogenetic data matrix for a major molluscan lineage to date, both in terms of taxon and character completeness. Exon capture targeting 490 of the 500 genes (those with at least one exon >120 bp) from 22 species of Australian Camaenidae successfully captured sequences of 2825 exons (representing all targeted genes), with only a 3.7% reduction in the data matrix due to the presence of putative paralogs or pseudogenes. The automated pipeline Agalma retrieved the majority of the manually qualified 500 single-copy gene set and identified a further 375 putative single-copy genes, although it failed to account for fragmented transcripts resulting in lower data matrix completeness when considering the original 500 genes. This could potentially explain the minor inconsistencies we observed in the supported topologies for the 21 eupulmonate species between the manually curated and 'Agalma-equivalent' data set (sharing 458 genes). Overall, our study confirms the utility of the 500 gene set to resolve phylogenetic relationships at a range of evolutionary depths and highlights the importance of addressing fragmentation at the homolog alignment stage for probe design. PMID:27289081

  11. First molecular identification of Australapatemon burti (Miller, 1923) (Trematoda: Digenea: Strigeidae) from an intermediate host Radix labiata (Rossmaessler) (Gastropoda: Lymnaeidae) in Europe.

    PubMed

    Aksenova, Olga V; Bespalaya, Yulia V; Bolotov, Ivan N; Kondakov, Alexander V; Sokolova, Svetlana E

    2016-01-01

    The strigeid digenean species Australapatemon burti (Miller, 1923) (Trematoda: Digenea: Strigeidae) was originally described from North America, but recorded in the Neotropical region (Drago et al. 2007; Hernández-Mena et al. 2014; Blasco-Costa et al. 2016) and in Central Europe (Faltýnková et al. 2007). In Europe, this species is rare, and there is not much information about its range (Faltýnková et al. 2007; Soldánová et al. 2012). Australapatemon burti has a complex life cycle with three larval stages, two of which (sporocyst and cercaria) use several species of freshwater snails, and the third stage (metacercaria) use non-specific host hirudineans (Dubois 1968; Davies & Ostrowski de Núñez 2012; Blasco-Costa et al. 2016). Adult flukes are parasitic in the intenstines of various waterfowl species, such as ducks and swans (Drago et al. 2007; Hernández-Mena et al. 2014). Currently, the molecular data on this parasite species includes only nucleotide sequences of four adult specimens from Mexico (Hernández-Mena et al. 2014). Their hosts were Mexican duck, Anas diazi Ridgway, American Wigeon, Anas americana Gmelin, Cinnamon Teal, Anas cyanoptera Vieillot, and Ruddy Duck, Oxyura jamaicensis (Gmelin) (Anserformes: Anatidae). PMID:27395696

  12. Solariella quadricincta Quinn, 1992 and S. staminea Quinn, 1992 are synonyms of S. carvalhoi Lopes & Cardoso, 1958 from the SW Atlantic (Gastropoda: Solariellidae).

    PubMed

    Cavallari, Daniel C; Salvador, Rodrigo B; Simone, Luiz R L

    2016-01-01

    Solariellidae is a diverse family of small (5-20 mm) marine snails of worldwide distribution. They usually live on fine sediment to unconsolidated substrates in deep-waters of extra-tropical to tropical latitudes (Hickman 1998; Williams et al. 2013). Initially described as a subfamily of Trochidae, it has been recently raised to family level (Bouchet et al. 2005; Williams et al. 2008). The evolutionary relationships among solariellids have been extensively investigated in the light of morphological and molecular data, but the family still lacks a comprehensive taxonomic revision that reflects recent discoveries (Williams et al. 2010, 2013). The family's fossil record possibly dates back to the Campanian of Torallola, Spain (Kiel & Bandel 2001; Williams et al. 2013). PMID:27394855

  13. Population genetic structure of the freshwater snail, Bulinus globosus, (Gastropoda: Planorbidae) from selected habitats of KwaZulu-Natal, South Africa.

    PubMed

    Mkize, Lwamkelekile Sitshilelo; Mukaratirwa, Samson; Zishiri, Oliver Tendayi

    2016-09-01

    The freshwater snail Bulinus globosus is an important intermediate host of Schistosoma haematobium, the causative agent of urinary schistosomiasis. This disease is of major health concern, especially in Africa where the majority of cases have been reported. In this study the inter- and intra-genetic diversity and population genetic structure of B. globosus from nine locations in the KwaZulu-Natal province of South Africa was studied using four polymorphic microsatellite loci (BgZ1-BgZ4). Moderate genetic diversity was detected within populations with a mean diversity (HE) of 0.49±0.09. The majority of populations significantly deviated from Hardy-Weinberg equilibrium (p<0.05), due to a deficit of heterozygotes. Such deviations may be due to founder events that were caused by bottlenecks that occurred as a result of frequent droughts and flooding that these snails' habitats are exposed to. Overall, the populations studied seem to be partially inbreeders/selfers with mean estimates of 0.24/0.38. A discernable genetic structure was elucidated among populations as evident by the mean pairwise FST of 0.58±0.13. There was no significant association between genetic and geographical distance among populations, an indication of limited gene flow. This increases the chances of populations losing alleles due to genetic drift. Populations in close proximity demonstrated high genetic differentiation (58.77% total variation) due to allelic differences between them. The sample populations fell into 12 clusters, however, the populations from uMkhanyakude and uThungulu exhibited no discernable genetic structure. Genetically, the Bhobhoyi site found within the uGu district was equidistant to the two main sampling regions. PMID:27267152

  14. Description of two new species of Rissoella Gray, 1847 (Mollusca, Gastropoda, Heterobranchia) from Venezuela, with a key to the Caribbean species known for the genus

    PubMed Central

    Caballer, Manuel; Ortea, Jesus; Narciso, Samuel

    2011-01-01

    Abstract Two new species of the genus Rissoella Gray, 1847 are described from Venezuela, one from the National Park Morrocoy, Rissoella morrocoyensis sp. n. and the other from the Wildlife Refuge Isla de Aves, Rissoella venezolanicola sp. n. Rissoella morrocoyensis sp. n. has a deep umbilicus (partly closed), preumbilical cord, black head, hypobranchial gland marked by a pale yellow boomerang-shaped ribbon and it lives on the leaves of the seagrass Thalassia testudinum Banks & König, 1805. Rissoella venezolanicola sp. n. has an angled preumbilical cord which extends to the columella delimiting a trapezoid, a hypobranchial gland marked by a yellow quaver-shaped ribbon and protoconch with fuchsia highlights. It lives on the brown alga Dictyota spp. The records of Rissoella in the Caribbean are revised and illustrations, a comparative table and a key to the Caribbean species known for the genus are provided. PMID:21976997

  15. Phylogenetic analysis of euthyneuran gastropods from sea to land mainly based on comparative mitogenomic of four species of Onchidiidae (Mollusca: Gastropoda: Pulmonata).

    PubMed

    Sun, Bian Na; Wei, Luan Luan; Shen, He Ding; Wu, Hong Xi; Wang, Dong Feng

    2016-09-01

    We generated complete mitochondrial genome sequences data for 4 genera (Onchidium, Platevindex, Paraoncidium and Peronia) in Onchidiidae to construct a phylogenetic tree in conjunction with other 9 existing data among gastropods. The topology showed that the taxa clustered into two main groups of four species, one of which included Onchidium struma and the Platevindex mortoni, the other Paraoncidium reevesii and Peronia verruculata. The process in Pulmonata from sea to land in accordance with the evolution of respiratory organs from branchial gills to pulmonary cavity has been shown. This will also constitute a framework for phylogeny evolution analysis, systematic classfication of Onchidiidae and other euthyneurans (pulmonates and opisthobranchs).

  16. The population genetic structure of Littorina littorea (Mollusca: Gastropoda) along a pollution gradient in the Scheldt estuary (The Netherlands) using RAPD analysis.

    PubMed

    De Wolf, Hans; Blust, Ronny; Backeljau, Thierry

    2004-06-01

    The population genetic structure of the periwinkle Littorina littorea was analysed using random amplified polymorphic DNA (RAPD). Three primers, coding for six putative polymorphic loci were surveyed to infer the genetic structure of seven populations located along the heavily polluted Western (i.e. in order of decreasing pollution load W1, W2, W3 and R1) and the relatively clean Eastern Scheldt (E1, E2 and E3) estuary (The Netherlands). A genetic distance based UPGMA (Unweighted pair group method with arithmetic mean) dendrogram revealed an estuary-related structuring, as Eastern and Western Scheldt sites formed two separate clusters. The Western Scheldt cluster was, however, much more heterogeneous, with three RAPD loci revealing a significant genetic heterogeneity compared to none when the Eastern Scheldt sites were compared. Overall mean heterozygosity levels were high, but did not reveal a difference between the estuaries. The current data (1) confirm the patterns of variation previously observed with electrophoretic analyses of esterases and (2) strongly support that these patterns of variation have a genetic basis, in the presence of intense gene flow. In addition, it is suggested that selection, rather than bottleneck effects, induced by the less favourable living conditions at W1, W2 and W3 are responsible for the genetic patterning. PMID:15144778

  17. Characterisation by X-ray microanalysis of metal granules in the mucus trails of Littorina littorea (Gastropoda) along a putative pollution gradient.

    PubMed

    Reboreda, R; Davies, Mark S

    2006-07-01

    Metal-containing granules in the mucus trails of the marine gastropod Littorina littorea from nine sites in north-east England were analysed for elemental composition by X-ray microanalysis and characterised relative to a putative gradient of pollution. Overall granule density varied significantly between sites, means of 6.5-17.0 per field of view (2688 microm2). Most granules found (64%) were poly-metal of a wide variety of compositions, but could be classified as Si+X, Mg+X, S+X, Na+X, P+Ca, P+Al, where X indicates any other combination of elements. Si+Al+X accounted for 61% of the poly-metal granules found and was considered to be contamination from the beach substratum. In single-metal granule form only Ca, Si, Fe, Ti, Al and Na were found. The most common single-metal granule at each site was of Ca, except at two sites, where the most common single-metal granule was of Si. The densities of these granule types varied between sites but differences were found to be significant only in the case of Si granules. Across all sites, single-metal granules of Si (mean = 2.49 microm +/- 1.44 SD, n = 141) and Ca (2.22 microm +/- 1.08 SD, n = 147) were significantly larger than granules of Fe (1.74 microm +/- 0.95 SD, n = 63) and Ti (1.24 microm +/- 0.52 SD, n = 18). The range of sizes was large: Ca (0.5-6 microm), Si (0.5-10 microm), Fe (0.3-4.1 microm), Ti (0.5-2.5 microm). Between the sites there were significant differences in the size of Fe and Si granules but not Ca or Ti granules. Despite these variations in granule type and size, there was no evidence of a relationship with pollution and consequently a detoxifying function of the mucus trail in metal polluted environments is not apparent. PMID:16622800

  18. Glowing Seashells: Diversity of Fossilized Coloration Patterns on Coral Reef-Associated Cone Snail (Gastropoda: Conidae) Shells from the Neogene of the Dominican Republic

    PubMed Central

    Hendricks, Jonathan R.

    2015-01-01

    The biology of modern Conidae (cone snails)—which includes the hyperdiverse genus Conus—has been intensively studied, but the fossil record of the clade remains poorly understood, particularly within an evolutionary framework. Here, ultraviolet light is used to reveal and characterize the original shell coloration patterns of 28 species of cone snails from three Neogene coral reef-associated deposits from the Cibao Valley, northern Dominican Republic. These fossils come from the upper Miocene Cercado Fm. and lower Pliocene Gurabo Fm., and range in age from about 6.6-4.8 Ma. Comparison of the revealed coloration patterns with those of extant species allow the taxa to be assigned to three genera of cone snails (Profundiconus, Conasprella, and Conus) and at least nine subgenera. Thirteen members of these phylogenetically diverse reef faunas are described as new species. These include: Profundiconus? hennigi, Conasprella (Ximeniconus) ageri, Conus anningae, Conus lyelli, Conus (Atlanticonus?) franklinae, Conus (Stephanoconus) gouldi, Conus (Stephanoconus) bellacoensis, Conus (Ductoconus) cashi, Conus (Dauciconus) garrisoni, Conus (Dauciconus?) zambaensis, Conus (Spuriconus?) kaesleri, Conus (Spuriconus?) lombardii, and Conus (Lautoconus?) carlottae. Each of the three reef deposits contain a minimum of 14–16 cone snail species, levels of diversity that are similar to modern Indo-Pacific reef systems. Finally, most of the 28 species can be assigned to modern clades and thus have important implications for understanding the biogeographic and temporal histories of these clades in tropical America. PMID:25830769

  19. New species of Rissoidae (Mollusca, Gastropoda) from the Archipelago of the Azores (northeast Atlantic) with an updated regional checklist for the family

    PubMed Central

    Cordeiro, Ricardo; Ávila, Sérgio P.

    2015-01-01

    Abstract Four new species of shallow-water marine gastropods belonging to the family Rissoidae are described from the Archipelago of the Azores: Setia alexandrae sp. n., Setia ermelindoi sp. n., Setia netoae sp. n., and Manzonia martinsi sp. n. These novelties increase the regional rissoid fauna to 39 species, of which 29 live in shallow-water habitats. A list of the species of Rissoidae from the Azores is presented based on data from the literature and new material examined. PMID:25685020

  20. Natural Prey Preferences and Spatial Variability of Predation Pressure by Cyphoma gibbosum (Mollusca: Gastropoda) on Octocoral Communities off La Parguera, Puerto Rico

    PubMed Central

    Lucas, Matthew Q.; Rodríguez, Luis R.; Sanabria, Duane J.

    2014-01-01

    This study evaluated the natural prey preferences and spatial variability of predation pressure (PP = proportion of colonies with snails and/or clear predation signs) by the gastropod Cyphoma gibbosum on octocoral communities off the La Parguera Natural Reserve, Puerto Rico. All octocoral colonies were checked for presence of C. gibbosum and/or clear predation signs in four permanent band-transects (2 × 10 m), along three depth intervals (0–5, 7–12, >15 m deep) in each of six reefs along an inshore offshore gradient. Results indicate that C. gibbosum preys on at least 16 species, six of which (Briareum asbestinum, Gorgonia ventalina, Pseudoterogorgia americana, P. acerosa, Plexaura flexuosa, and Pseudoplexaura porosa) consistently showed significantly higher (K-W, P < 0.05) (17–37%) PP compared to all other species. Plexaura flexuosa, P. americana, and P. porosa had significantly higher PP (11–38%) among inner and mid-shelf reefs, and G. ventalina had higher PP in shelf-edge reefs (16–20%). A combination of differential spatial distributions and octocoral species abundances seems to explain the observed patterns of predation by C. gibbosum. Prey preference and higher abundances of 3-dimensional octocorals providing increased refuge or microhabitats utilized for mating or egg-deposition could be driving the spatial distribution of C. gibbosum and the observed differential predation pressure. PMID:27433523

  1. Irrigation canals in Melo creek basin (Rio Espera and Capela Nova municipalities, Minas Gerais, Brazil): habitats to Biomphalaria (Gastropoda: Planorbidae) and potential spread of schistosomiasis.

    PubMed

    Leite, M G P; Pimenta, E C; Fujaco, M A G; Eskinazi-Sant'Anna, E M

    2016-04-19

    This study analyzed the presence of Biomphalaria in Melo creek basin, Minas Gerais state, and its relationship to irrigation canals. Seventeen of these canals were used to determine a limnological, morphological and hydrological characterization during an annual seasonal cycle. Biomphalaria samples were sent to René Rachou Research Center/FIOCRUZ for identification and parasitological examination. Six canals were identified as breeding areas for mollusks and in one of them it was registered the coexistence of B. tenagophila (first report to this basin) and B. glabrata species. Results indicated that the low flow rate and speed of water flow were the main characteristics that contributed to this specific growth of the mollusks in the area. These hydraulic characteristics were created due to anthropogenic action through the canalization of lotic areas in Melo creek, which allowed ideal ecological conditions to Biomphalaria outbreak. The results emphasize the need of adequate handling and constant monitoring of the hydrographic basin, subject to inadequate phytosanitary conditions, aiming to prevent the occurrence and propagation of schistosomiasis. PMID:27097093

  2. Influence of egg cannibalism on growth, survival and feeding in hatchlings of the land snail Helix aspersa Müller (Gastropoda, Pulmonata, Stylommatophora).

    PubMed

    Desbuquois, C

    1997-01-01

    Under controlled conditions, growth, survivorship and several nutritional parameters (ingestion, egestion and assimilation) were measured weekly in hatchlings that either ate a conspecific egg after birth (cannibalistic) or not (non-cannibalistic) and in food-deprived individuals (control group). Subsequently, the snails were fed on Taraxacum officinale. After 4 days, cannibalistic snails were 1.3 times heavier than food-deprived snails and 100% survived (75.8% in the control group and 40% of the non-cannibalistic individuals). Mortality, particularly in smaller snails, might be a consequence of food deprivation. Nutritional and energetic gains of oophagy increased both future survivorship and growth. After 11 weeks, cannibalistic snails were 1.4 times heavier and had higher survival rates than food-deprived ones although ingestion, egestion rates and assimilation efficiency were similar in both groups. The larger wet weight of cannibalistic snails after 4 days induced a higher food consumption and thus a higher growth rate. The influence of oophagy on life-history traits is discussed in relation to costs and benefits.

  3. The influence of self-fertilization and pairing on life-history traits in the freshwater snail Bulinus forskalii (Gastropoda, planorbidae).

    PubMed

    Njiokou, F; Mouafo, J B; Teukeng, F; Njine, T; Ekobo, A S; Jarne, P

    2000-09-18

    This study analyses the basic reproductive biology of the schistosonie-vector snail Bulinus forskalli. This hermaphroditic species can self-fertilize. Variation of the mating system was analysed in two populations from Cameroon in a three-step experiment. (i) The fecundity (number of eggs and of egg capsules) of isolated virgin individuals from both populations was followed over a month, as well as the survival of offspring from these individuals. Estimates of these parameters were intermediate. Our results also indicate that inbreeding depression has a maximum value of about one-half in both populations. No difference was observed between populations for both the overall fecundity of adults and survival of offspring. (ii) Individuals were then paired either within, or between populations over three successive days, and the number of copulations recorded. Copulations were observed in all situations, including between-population pairs. No significant dlifference in the number of copulations per pair was detected. However, this value decreased with time, and reciprocal copulations were significantly less numerous between than within populations. (iii) Individuals that successfully copulated as female in (ii) were isolated, and their fecundity was followed over 3 weeks. The fecundity of individuals that had been maintained isolated over the whole experiment served as a control. No significant difference was on the whole detected. Our results collectively suggest that the individuals from the two populations studied are rather selfers, confirming that B. forskalii is a preferentially selfing species. There is also some pre-zygotic isolation against crosses between populations.

  4. Phylogenetic analysis of Euthyneura (Gastropoda) by means of the 16S rRNA gene: use of a 'fast' gene for 'higher-level' phylogenies

    PubMed Central

    Thollesson, M.

    1999-01-01

    The phylogeny of Euthyneura is analysed by using DNA sequences of the mitochondrial 16S rRNA gene. Despite the common notion that this gene is too variable to provide useful information at high taxonomic levels, such as in the present study, bootstrap proportions are high for several clades in the study. This indicates that there is a useful amount of variation despite the noise due to multiple substitutions. The analyses furthermore indicate that (i) Gymnosomata (represented by Clione) is not a part of Euthyneura, but Clione forms a clade with the caenogastropods; (ii) Acteon is the sister group to the remaining euthyneuran taxa in the study; (iii) the nudibranch taxa form two clades, one comprising Dendronotoidea, Arminoidea and Aeolidoidea (together Cladobranchia) with Notaspidea (represented by Berthella) as sister group, while the fourth nudibranch taxon, Doridoidea, forms a separate clade; (iv) Cephalaspidea s.s. and Anaspidea form clades that are each other's sister groups (together Pleurocoela). Finally, there is no clade present in the analyses corresponding to the taxon Opisthobranchia in the traditional sense, and the use of this name is probably better abandoned altogether.

  5. Long-term changes in Prosobranchia (Gastropoda) abundances on the German North Sea coast: the role of the anti-fouling biocide tributyltin

    NASA Astrophysics Data System (ADS)

    Nehring, S.

    2000-05-01

    Tributyltin (TBT) has been used as a biocide in marine anti-fouling paints since the early 1970s. Due to its strong ecotoxicity and the relatively high levels in the water column as well as in port sediments on the German North Sea coast, it probably has negative ecological effects on organisms other than those targeted. An analysis of the long-term development of prosobranch stocks in the inner German Bight reveals a decrease in abundance of many species. For most species the decline cannot be attributed to TBT, but in four prosobranch species ( Buccinum undatum, Hydrobia ulvae, Littorina littorea and Nucella lapillus) significant ecological effects by TBT pollution are very probable. Although research for alternative non-TBT anti-fouling paints (e.g. biocide-free types on the basis of silicone) has been intensified, the potential threats to ecosystems and the ecotoxicological profiles of these alternatives have to be carefully evaluated.

  6. Four new species of splanchnotrophid copepods (Poecilostomatoida) parasitic on doridacean nudibranchs (Gastropoda, Opistobranchia) from Japan, with proposition of one new genus

    PubMed Central

    Uyeno, Daisuke; Nagasawa, Kazuya

    2012-01-01

    Abstract Four new species of splanchnotrophid copepods are described based on specimens collected from 5 species of doridacean nudibranchs from coastal waters of Japan. They belong to 3 genera, one of which, Majimun gen. n., is new. The parasites and their hosts are as follows: Ceratosomicola japonica sp. n. ex Hypselodoris festiva (A. Adams); Splanchnotrophus helianthus sp. n. ex Thecacera pennigera (Montagu); Splanchnotrophus imagawai sp. n. ex Trapania miltabrancha Gosliner & Fahey; and Majimun shirakawai gen. et sp. n. ex Roboastra luteolineata (Baba) and Roboastra gracilis (Bergh). Ceratosomicola japonica sp. n. is the fifth species of Ceratosomicola and is characterized by the shape and armature of the prosome in females. Both Splanchnotrophus helianthus sp. n. and Splanchnotrophus imagawai sp. n. are differentiated from 4 known congeners by the absence of posterolateral processes or lobes on the prosome in females, and the females of these 2 new species are separated from each other by the shape and armature of the genito-abdomen, the mandible, and the swimming legs. Majimun gen. n. is distinguished from other splanchnotrophid genera by the segmentation of the antennule as well as the combination of the following characters in females: 2 postgenital somites and the shape of the antenna, the mandible and the swimming legs. PMID:23275753

  7. Environmental Epidemiology of Intestinal Schistosomiasis in Uganda: Population Dynamics of Biomphalaria (Gastropoda: Planorbidae) in Lake Albert and Lake Victoria with Observations on Natural Infections with Digenetic Trematodes

    PubMed Central

    Rowel, Candia; Fred, Besigye; Sousa-Figueiredo, Jose C.; Kabatereine, Narcis B.; Stothard, J. Russell

    2015-01-01

    This study documented the population dynamics of Biomphalaria and associated natural infections with digenetic trematodes, along the shores of Lake Albert and Lake Victoria, recording local physicochemical factors. Over a two-and-a-half-year study period with monthly sampling, physicochemical factors were measured at 12 survey sites and all freshwater snails were collected. Retained Biomphalaria were subsequently monitored in laboratory aquaria for shedding trematode cercariae, which were classified as either human infective (Schistosoma mansoni) or nonhuman infective. The population dynamics of Biomphalaria differed by location and by lake and had positive relationship with pH (P < 0.001) in both lakes and negative relationship with conductivity (P = 0.04) in Lake Albert. Of the Biomphalaria collected in Lake Albert (N = 6,183), 8.9% were infected with digenetic trematodes of which 15.8% were shedding S. mansoni cercariae and 84.2% with nonhuman infective cercariae. In Lake Victoria, 2.1% of collected Biomphalaria  (N = 13,172) were infected with digenetic trematodes with 13.9% shedding S. mansoni cercariae, 85.7% shedding nonhuman infective cercariae, and 0.4% of infected snails shedding both types of cercariae. Upon morphological identification, species of Biomphalaria infected included B. sudanica, B. pfeifferi, and B. stanleyi in Lake Albert and B. sudanica, B. pfeifferi, and B. choanomphala in Lake Victoria. The study found the physicochemical factors that influenced Biomphalaria population and infections. The number and extent of snails shedding S. mansoni cercariae illustrate the high risk of transmission within these lake settings. For better control of this disease, greater effort should be placed on reducing environmental contamination by improvement of local water sanitation and hygiene. PMID:25705680

  8. A new species of Gudeodiscus Páll-Gergely, 2013 from China, with extraordinary conchological and anatomical features (Gastropoda, Pulmonata, Plectopylidae)

    PubMed Central

    Páll-Gergely, Barna; Asami, Takahiro

    2016-01-01

    Abstract A new species of the Plectopylidae, Gudeodiscus longiplica is described from northern Guangxi Province, southern China. The shell, anatomical and radular characters are figured and described. This new species is characterized by long plicae on its parietal shell wall, which have not been observed in any other Gudeodiscus species. In contrast, the long parietal plicae are characteristic for the genera Plectopylis and Chersaecia, which mainly inhabit Thailand and Myanmar. These two genera are, however, only distantly related to the new species, as other characters (anatomy, protoconch sculpture, parietal plicae) suggest. The male portion of the genital structure of the new species is characterized by two separate penial caeca with different lengths, but similar in outer and inner structure. The relevance of this anatomical character is discussed. Gudeodiscus longiplica sp. n. occurs sympatrically with Gudeodiscus soosi Páll-Gergely, 2013. The anatomy and radula characters of the latter species are also described and figured. PMID:27081330

  9. DNA sequence characterisation and phylogeography of Lymnaea cousini and related species, vectors of fascioliasis in northern Andean countries, with description of L. meridensis n. sp. (Gastropoda: Lymnaeidae)

    PubMed Central

    2011-01-01

    Background Livestock fascioliasis is a problem throughout Ecuador, Colombia and Venezuela, mainly in Andean areas where the disease also appears to affect humans. Transmission patterns and epidemiological scenarios of liver fluke infection have shown to differ according to the lymnaeid vector snail species involved. These Andean countries present the vectors Lymnaea cousini, L. bogotensis and L. ubaquensis, unknown in the rest of Latin America. An exhaustive combined haplotype study of these species is performed by means of DNA sequencing of the nuclear ribosomal 18S RNA gene, ITS-2 and ITS-1, and mitochondrial DNA cox1 gene. Results The conserved 5.8S rDNA sequence corroborated that no pseudogenes are involved in the numerous non-microsatellite/minisatellite-related indels appearing between the ITS-2 and ITS-1 sequences when comparing different L. cousini - L. bogotensis populations. Sequence analyses and phylogenetic reconstruction methods including other lymnaeid vector species show that (i) L. bogotensis is a synonym of L. cousini, (ii) L. ubaquensis is a synonym of Pseudosuccinea columella, and (iii) populations of L. cousini hitherto known from Venezuelan highlands indeed belong to a new species for which the name L. meridensis n. sp. is proposed. This new species is described and a complete phenotypic differentiation provided. Conclusions ITS-2, ITS-1 and cox1 prove to be good markers for specimen classification and haplotype characterisation of these morphologically similar lymnaeids in endemic areas. Analysis of the 18S gene and phylogenetic reconstructions indicate that L. cousini and L. meridensis n. sp. cluster in an evolutionary line different from the one of P. columella, despite their external resemblance. This suggests an evolutionary phenotypic convergence related to similar environments and which has given rise to frequent specimen misclassification. Body size and phylogenetic relationships of L. meridensis n. sp. with well-known vectors as Lymnaea cousini and P. columella, as well as with Galba/Fossaria species, suggest that the new species may participate in disease transmission to both animals and humans in altitude areas during the yearly window in which temperatures are higher than the F. hepatica minimum development threshold. The involvement of L. cousini and P. columella in the transmission and geographical/altitudinal distribution of fascioliasis in these Andean countries is analysed. PMID:21749718

  10. Cellular, biochemical, and molecular characterization of nitric oxide synthase expressed in the nervous system of the prosobranch Stramonita haemastoma (Gastropoda, Neogastropoda).

    PubMed

    Cioni, Carla; Di Patti, Maria Carmela Bonaccorsi; Venturini, Giorgio; Modica, Maria Vittoria; Scarpa, Francesca; Oliverio, Marco; Toni, Mattia

    2012-02-01

    Nitric oxide synthase (NOS) has been characterized in several opistobranchs and pulmonates but it was much less investigated in prosobranchs, which include more than 20,000 species and account for most of the gastropod diversity. Therefore, new data from this large group are needed for a better knowledge of the molecular evolution of NOS enzymes in molluscs. This study focused on NOS expressed in the nervous system of the prosobranch neogastropod Stramonita haemastoma. In this study we report compelling evidence on the expression of a constitutive Ca(2+) /CaM-dependent neuronal NOS in the central and peripheral nervous system. The prevailing neuronal localization of NADPHd activity was demonstrated by NADPHd histochemistry in both central and peripheral nervous system structures. L-arginine/citrulline assays suggested that Stramonita NOS is a constitutive enzyme which is both cytosolic and membrane-bound. Molecular cloning of the full-length Stramonita NOS (Sh-NOS) by reverse-transcription polymerase chain reaction (RT-PCR) followed by 5' and 3' RACE showed that Sh-NOS is a protein of 1,517 amino acids, containing a PDZ domain at the N-terminus and sharing similar regulatory domains to the mammalian neuronal NOS (nNOS). Regional expression of the Sh-NOS gene was evaluated by RT-PCR. This analysis showed different expression levels in the nerve ring, the osphradium, the cephalic tentacles, the buccal tissues, and the foot, whereas NOS expression was not found in the salivary glands and the gland of Leiblein. The present data provide a solid background for further studies addressing the specific functions of NO in neogastropods.

  11. Arresting mantle formation and redirecting embryonic shell gland tissue by platinum2+ leads to body plan modifications in Marisa cornuarietis (Gastropoda, Ampullariidae).

    PubMed

    Marschner, Leonie; Triebskorn, Rita; Köhler, Heinz-R

    2012-08-01

    To evaluate the threat that anthropogenic substances pose to animals when they are emitted into the environment, tests like the invertebrate embryo toxicity test with the ramshorn snail Marisa cornuarietis have been developed. These tests are used to investigate substances like the heavy metal platinum (Pt) that is used in catalytic converters and is gradually released in car exhausts. In 2010, our group reported that high Pt concentrations cause body plan alterations in snails and prevent the formation of an external shell during M. cornuarietis embryogenesis. Now, this study presents scanning-electron micrographs and histological sections of platinum(2+) (Pt(2+))-treated and untreated M. cornuarietis embryos and compares "normally" developing and "shell-less" embryos during embryogenesis, to reveal the exact course of events that lead to this body plan shift. Both groups showed similar development until the onset of torsion 70- to 82-h postfertilization. In the Pt(2+)-exposed embryos, the rudimentary shell gland (=anlage of both shell gland and mantle, which usually evaginates, grows, and eventually covers the visceral sac) does not spread across the visceral sac but remains on its ventral side. Without the excessive growth of the shell gland, a horizontal rotation of the visceral sac relative to head and foot does not occur, as being normal during the process of torsion.

  12. Report on the occurrence of Angiostrongylus costaricensis in southern Brazil, in a new intermediate host from the genus Sarasinula (Veronicellidae, Gastropoda).

    PubMed

    Laitano, A C; Genro, J P; Fontoura, R; Branco, S S; Maurer, R L; Graeff-Teixeira, C; Milanez, J M; Chiaradia, L A; Thomé, J W

    2001-01-01

    Veronicellid slugs are the main intermediate hosts for Angiostrongylus costaricencis. In a rural locality in Nova Itaberaba (SC, southern Brazil) Sarasinula linguaeformis was identified as a crop pest. The parasitological examination revealed A. costaricencis infection in 43 out ot 50 slugs. The prevalence of 86% and the individual parasitic burdens are the highest sofar reported in Brazil and S. linguaeformis is the first species from the genus Sarasinula to be identified as intermediate host for A. costaricencis in southern Brazil.

  13. Annotated type catalogue of the Orthalicoidea (Mollusca, Gastropoda) in the Royal Belgian Institute of Sciences, Brussels, with descriptions of two new species

    PubMed Central

    Breure, Abraham S.H.

    2011-01-01

    Abstract The type status is described of 57 taxa from the superfamily Orthalicoidea in the collection of the Brussels museum. Two new species are described: Stenostylus perturbatus sp. n., and Suniellus adriani sp. n. New lectotypes are designated for Bulimulus (Naesiotus) amastroides Ancey, 1887; Bulimulus blanfordianus Ancey, 1903; Bulimulus montivagus chacoensis Ancey, 1897; Bulimus coloratus Nyst, 1845; Plecochilus dalmasi Dautzenberg, 1900; Placostylus porphyrostomus elata Dautzenberg, 1923; Bulimulus ephippium Ancey, 1904; Bulimus fulminans Nyst, 1843; Bulimus funckii Nyst, 1843; Orphnus thompsoni lutea Cousin, 1887; Bulimus melanocheilus Nyst, 1845; Orphnus thompsoni nigricans Cousin, 1887; Orphnus thompsoni olivacea Cousin, 1887; Bulimulus pollonerae Ancey, 1897; Orphnus thompsoni zebra Cousin, 1887. New combinations are: Bostryx borellii (Ancey, 1897); Bostryx carandaitiensis (Preston, 1907); Protoglyptus mazei (Crosse, 1874); Kuschelenia (Vermiculatus) sanborni (Haas, 1947). New synonymies are established for the following nominal taxa: Orphnus thompsoni var. lutea Cousin, 1887 = Kara thompsonii (Pfeiffer, 1845); Orphnus thompsoni var. nigricans Cousin, 1887 = Kara thompsonii (Pfeiffer, 1845); Thaumastus nystianus var. nigricans Cousin, 1887 = Drymaeus (Drymaeus) nystianus (Pfeiffer, 1853); Orphnus thompsoni var. olivacea Cousin, 1887 = Kara thompsonii (Pfeiffer, 1845); Orphnus thompsoni var. zebra Cousin, 1887 = Kara thompsonii (Pfeiffer, 1845). PMID:21747669

  14. Calyptraeotheres sp. nov. (Crustacea: Decapoda: Pinnotheridae), symbiont of the slipper shell Crepidula striolata Menke, 1851 (Mollusca: Gastropoda: Calyptraeidae) from the Gulf of California, Mexico.

    PubMed

    Ayón-Parente, Manuel; Hendrickx, Michel E

    2014-10-07

    Calyptraeotheres camposi sp. nov. is described from the Gulf of California, Mexico. The new species is close to C. granti (Glassell, 1933) and C. pepeluisi Campos & Hernández-Ávila, 2010 from the Mexican Pacific and to C. hernandezi Hernández-Ávila & Campos 2006 from the Western Atlantic. These four species feature a third maxilliped with a 2-segmented endopod palp and the exopod with unsegmented flagellum. Calyptraeotheres camposi sp. nov. differs from C. granti and C. hernandezi by having the eyes visible in dorsal view, the carapace with arcuate anterolateral margins, the dorsal, longitudinal depressions connected with the transversal depression, and the propodus of pereiopod 2 equal or slightly longer than the carpus. From C. pepeluisi it is distinguished by the absence of a transversal depression on the carapace and the longitudinal depressions not connecting, the carpus and propodus of the third maxilliped being sub-trapezoidal and sub-conical, respectively, in lieu of subrectangular, and the inner surface of the fixed finger nude instead of bearing short setae near the cutting edge and ventral margin.

  15. Catalog of the recent taxa of the families Epitoniidae and Nystiellidae (Mollusca: Gastropoda) with a bibliography of the descriptive and systematic literature.

    PubMed

    Brown, Leonard G; Neville, Bruce D

    2015-01-15

    This catalog includes 1,487 names recent genera, subgenera, species, subspecies, varieties, and forms that have been referred to the families Epitoniidae and Nystiellidae as well as a bibliography of the descriptive and systematic literature associated with these names. For the names covered herein, we make a determination of whether the name is an available name, as that term is defined in the International Code of Zoological Nomenclature ("ICZN") and, based on a review of the literature listed in the bibliography, indicate whether the taxon is a potentially valid name or a probable synonym. This catalog includes not only includes a list of names, but also includes information on type material, type localities and species' geographic, bathymetric and size ranges. We also suggest generic assignments for many of the species level taxa listed in this work. We herein designate Scalaria acuta J. Sowerby, 1812, to be the type species of Clathrus Agassiz, 1837, designate Scalaria raricostata G.B. Sowerby II, 1844b, to be the type species of Variciscala de Boury, 1909a, designate Turbiniscala sexcosta Jousseaume, 1912, to be the type species of Turbiniscala de Boury, 1909a, and designate Scala dubia 'G. B. Sowerby II' de Boury, 1912b to be the type species of Foliaceiscala de Boury, 1912b. 

  16. A new species of Tambja (Mollusca, Gastropoda, Nudibranchia) from the Mediterranean Sea: description of the first species of the genus from the Balearic Islands and Malta

    NASA Astrophysics Data System (ADS)

    Domínguez, M.; Pola, M.; Ramón, M.

    2015-06-01

    A new species of polycerid nudibranchs of the genus Tambja is described from Mallorca Island (Spain) and Malta. So far, only two species of Tambja had been recorded in the Mediterranean Sea with a distribution limited to southern Spain. With Tambja mediterranea sp. nov., the distribution of the genus in the Mediterranean Sea is extended, and the new species represents the first occurrence of Tambja at the Balearic Islands and Malta. Externally, the new species is mainly characterized by having ground orange-red colour, dorsum covered with rounded whitish tubercles, rhinophores red with whitish tips and three gill branches with orange-reddish rachis and whitish branches. In the present paper, external and internal features of T. mediterranea are described and compared with other species of the genus, especially with its most similar species, T. limaciformis. Additionally, phylogenetic analyses (Bayesian and maximum likelihood) based on mitochondrial sequences (COI) show that T. mediterranea sp. nov. is sister to T. divae and that both species cluster together with T. limaciformis and T. amakusana with the maximum support.

  17. Ontogenetic changes in feeding and food preferences of the dog conch Laevistrombus canarium Linnaeus 1758 (Mollusca: Gastropoda) from Merambong shoal, Malaysia

    NASA Astrophysics Data System (ADS)

    Husna, Wan Nurul Wan Hassan; Mazlan, Abd Ghaffar; Cob, Zaidi Che

    2016-10-01

    Laevistrombus canarium is one of the marine gastropod mollusks that have high commercial value, particularly in the aquaculture sector in Malaysia. This study was conducted to determine the feeding and food items of L. canarium at different ontogenetic stages (juveniles, sub-adults and adults) from Merambong shoals, Malaysia. Field observations on feeding activity were conducted, followed by detailed laboratory analysis on the stomach content. Five-minutes observations on randomly selected individuals were conducted at the field sampling site and their feeding activities were recorded with reference to age stage. Various shell sizes from each ontogenetic stage were randomly collected and quickly anaesthetized with ice and preserved in 10% formalin before being transported to the laboratory for stomach content analyses. Field observations showed that L. canarium mainly grazed on epiphytes occurring on seagrass (46.67%), followed by sediment surface (40%) and epiphytes occurring on macroalgae (13.33%). Stomach content analyses showed a significant difference (P <0.05) in gastro-somatic index (Gasi) between the juveniles (0.39±0.05), sub-adults (0.68±0.09) and adults (0.70±0.05) (P <0.05). Food items found in the conch stomach include diatoms, detritus, foraminifera, seagrass and macroalgae fragments, sand particles and shell fragments. The Index of Relative Importance (%IRI) indicates three main types of food dominated the three ontogenetic stages namely diatoms, sand particles and detritus. However, no significant difference (P >0.05) was detected between the three main food items (diatoms, sand particles and detritus) among the ontogenetic stages. Therefore, feeding activity revealed the role of the dog conch in the marine food network. While, classification of the types of food consumed by L. canarium through stomach content analysis determines the particular position of the gastropod in the food chain. Further studies are needed to provide a better insight between trophic relationships of L. canarium with marine ecosystem.

  18. Sclerochronology - a highly versatile tool for mariculture and reconstruction of life history traits of the queen conch, textit{Strombus gigas} (Gastropoda)

    NASA Astrophysics Data System (ADS)

    Radermacher, Pascal; Schöne, Bernd R.; Gischler, Eberhard; Oschmann, Wolfgang; Thébault, Julien; Fiebig, Jens

    2010-05-01

    The shell of the queen conch Strombus gigas provides a rapidly growing palaeoenvironmental proxy archive, allowing the detailed reconstruction of important life-history traits such as ontogeny, growth rate and growth seasonality. In this study, modern sclerochronological methods are used to cross-date the palaeotemperatures derived from the shell with local sea surface temperature (SST) records. The growth history of the shell suggests a bimodal seasonality in growth, with the growing season confined to the interval between April and November. In Glovers Reef, offshore Belize, the queen conch accreted shell carbonate at rates of up to 6 mm day-1 during the spring (April-June) and autumn (September-November). However a reduced period of growth occurred during the mid-summer months (July-August). The shell growth patterns indicate a positive response to annual seasonality with regards to precipitation. It seems likely that when precipitation levels are high, food availability is increased as the result of nutrient input to the ecosystem in correspondence with an increase in coastal runoff. Slow growth rates occur when precipitation, and as a consequence riverine runoff, is low. The SST however appears to influence growth only on a secondary level. Despite the bimodal growing season and the winter cessation in growth, the growth rates reconstructed here from two S. gigas shells are among the fastest yet reported for this species. The S. gigas specimens from Belize reached their final shell height (of 22.7 and 23.5 cm in distance between the apex and the siphonal notch) at the transition to adulthood in just 2 years. The extremely rapid growth as observed in this species permits detailed, high-resolution reconstructions of life-history traits where sub-daily resolutions can be achieved with ease. The potential for future studies has yet to be further explored. Queen conch sclerochronology provides an opportunity to recover extremely high-resolution palaeotemperature records, which could be used to improve numeric climate models, where the shells essentially function as mineralized buoys. The shell recorder may also help to reveal changes in biogeochemical dynamics in benthic ecosystems on intra-seasonal timescales in the fossil record. Furthermore, sclerochronology provides a rapid, effective and highly versatile investigative strategy when compared to time- and cost-consuming fieldwork for improving fisheries management and maricultural pursuits.

  19. Activation of anaerobic metabolism in Biomphalaria glabrata (Mollusca: Gastropoda) experimentally infected by Angiostrongylus cantonensis (Nematoda, Metastrongylidae) by high-performance liquid chromatography.

    PubMed

    Tunholi-Alves, Vinícius Menezes; Tunholi, Victor Menezes; Castro, Rosane N; Sant'Ana, Luiza D'Oliveira; Santos-Amaral, Luciana; de Oliveira, Ana Paula Martins; Garcia, Juberlan; Thiengo, Silvana Carvalho; Pinheiro, Jairo; Maldonado, Arnaldo

    2014-02-01

    The activity of lactate dehydrogenase and the concentrations of glucose in the hemolymph and of glycogen in the digestive gland and cephalopedal mass of Biomphalaria glabrata experimentally infected with Angiostrongylus cantonensis were evaluated. Additionally, high performance liquid chromatography (HPLC) was used to determine the hemolymph concentrations of some carboxylic acids (oxalic, piruvic, lactic and succinic). After one, two and three weeks of infection, the snails were dissected to collect the hemolymph and separate the tissues. A significant reduction of the levels of glucose in the hemolymph was observed as of the first week of infection in relation to the control group. The lactate dehydrogenase activity of the infected group was significantly higher than the average of the control group. This increase was accompanied by a reduction of the levels of piruvic acid and an increase in the levels of lactic acid in the hemolymph of the parasited snails, confirming the acceleration of the anaerobic metabolism, necessary for the host to obtain energy and maintain its redox balance. In parallel, there was a decrease in the glycogen content of the storage tissues, with that reduction being significantly greater in the cephalopedal mass than the digestive gland, demonstrating that in this interaction system, the mobilization of glycogen was not sufficient to maintain and reestablish the normal glycemia of the infected snails.

  20. Evaluation of the mitochondrial system in the gonad-digestive gland complex of Biomphalaria glabrata (Mollusca, Gastropoda) after infection by Echinostoma paraensei (Trematoda, Echinostomatidae).

    PubMed

    Tunholi, Victor Menezes; Tunholi-Alves, Vinícius Menezes; Santos, Anderson Teixeira; Garcia, Juberlan da Silva; Maldonado, Arnaldo; da-Silva, Wagner Seixas; Rodrigues, Maria de Lurdes de Azevedo; Pinheiro, Jairo

    2016-05-01

    The effect of infection by Echinostoma paraensei on the mitochondrial physiology of Biomphalaria glabrata was investigated after exposure to 50 miracidia. The snails were dissected one, two, three and four weeks after infection for collection and mechanical permeabilization of the gonad-digestive gland (DGG) complex. The results obtained indicate that prepatent infection by this echinostomatid fluke significantly suppresses the phosphorylation state (respiratory state 3) and basal oxygen consumption of B. glabrata, demonstrating that the infection reduces the ability of the intermediate host to carry out aerobic oxidative reactions. Additionally, relevant variations related to the uncoupled mitochondrial (state 3u) of B. glabrata infected by E. paraensei were observed. Four weeks after exposure, a significant reduction in mitochondrial oxygen consumption after addition of ADP (3.68±0.26pmol O2/mg proteins) was observed in the infected snails in comparison with the respective control group (5.14±0.25). In the uncoupled state, the infected snails consumed about 62% less oxygen than the infected snails (7.87±0.84pmol O2/mg proteins) in the same period. These results demonstrate a reduction in oxidative decarboxylation rate of the tricarboxylic acid cycle and faster anaerobic degradation of carbohydrates in the infected snails. The possible mechanisms that explain this new metabolic condition in the infected organisms are discussed.

  1. Presence of ACTH and beta-endorphin immunoreactive molecules in the freshwater snail Planorbarius corneus (L.) (Gastropoda, Pulmonata) and their possible role in phagocytosis.

    PubMed

    Ottaviani, E; Petraglia, F; Montagnani, G; Cossarizza, A; Monti, D; Franceschi, C

    1990-01-01

    The presence of ACTH and beta-endorphin immunoreactive molecules in the cell-free hemolymph and in the hemocytes of the freshwater snail Planorbarius corneus were demonstrated by immunocytochemistry and RIA tests. Only spreading phagocytic hemocytes were positive, in contrast with other hemocytes devoid of phagocytic activity, i.e., round hemocytes. These data were confirmed by flow cytometry. Another cell type with marked phagocytic activity, i.e., digestive cells of digestive gland, were also positive to anti-ACTH. Corticotropin-releasing factor immunoreactive molecules were found in the cell-free hemolymph and hemocytes, by RIA. Our data suggest that cells with phagocytic activity, the oldest immune response, may represent a suitable model to unravel the tangled web of the common ancestor of the immune and the neuroendocrine systems.

  2. 76 FR 33360 - National Register of Historic Places; Notification of Pending Nominations and Related Actions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-08

    ... County Gramse, The, 2203 Broadway St., Indianapolis, 11000384 Indianapolis White Castle Number 3, 660 Fort Wayne Ave., Indianapolis, 11000385 Porter County Bloch, Conrad and Catherine, House, 608...

  3. Brokering at the boundary: A prospective science teacher engages students in inquiry

    NASA Astrophysics Data System (ADS)

    Meis Friedrichsen, Patricia; Munford, Danusa; Orgill, Marykay

    2006-05-01

    Using a theoretical perspective of communities of practice, this case study examines a prospective chemistry teacher's inquiry-based teaching during his practicum. Conrad was a former student of an inquiry-oriented science course, Inquiry Empowering Technologies (IET). The research questions were (a) How did Conrad translate the IET inquiry practices during his practicum?; (b) How did the mentor teacher shape Conrad's participation?; (c) In what ways did Conrad negotiate new meanings of inquiry as a result of his practicum? Interview transcripts were the primary data source. Conrad carried many of the IET inquiry practices into his practicum. He equated inquiry with the use of evidence and had students create evidence-based explanations for how soap works. He chose not to incorporate the tentative nature of science. Although traditional in his own teaching, the mentor teacher supported Conrad by allowing him to teach through inquiry and by removing time constraints. As a result of his practicum, Conrad negotiated new meanings of inquiry teaching and developed an expanded view of technology. Conrad believed that high school students needed guidance when engaging in inquiry and that the tentative nature of science does not transfer to secondary chemistry. Implications for theory and practice are given.

  4. Brokering at the Boundary: A Prospective Science Teacher Engages Students in Inquiry

    ERIC Educational Resources Information Center

    Friedrichsen, Patricia Meis; Munford, Danusa; Orgill, MaryKay

    2006-01-01

    Using a theoretical perspective of communities of practice, this case study examines a prospective chemistry teacher's inquiry-based teaching during his practicum. Conrad was a former student of an inquiry-oriented science course, "Inquiry Empowering Technologies" (IET). The research questions were (a) How did Conrad translate the IET inquiry…

  5. Skylab Dental Examination

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Skylab 2 Commander Charles Conrad is seen undergoing a dental examination by the Medical Officer, Joseph Kerwin in the Skylab Medical Facility. In the absence of an examination chair, Conrad simply rotated his body to an upside down position to facilitate the procedure.

  6. Folklore and the College Selection Process Revisited

    ERIC Educational Resources Information Center

    Caruso, Pete

    2012-01-01

    This paper is a response to Clinton F. Conrad's article, "Beyond the Folklore." Conrad's strategy for assessing undergraduate quality echoes the sentiments espoused by many admission and college counseling professionals over the years at various workshops for students and families that focus on navigating the process. As transcendent as the…

  7. Off-shore to near-shore transects of ferromanganese crusts adjacent to the California margin Tracey A. Conrad1, James R. Hein2, Adina Paytan1 1University of California Santa Cruz, CA, 95064 (tconrad@ucsc.edu) 2USGS, Menlo Park, CA, 94025, USA (jhein@usgs.gov)

    NASA Astrophysics Data System (ADS)

    Conrad, T. A.; Hein, J. R.; Paytan, A.

    2012-12-01

    Marine ferromanganese (Fe-Mn) crusts growing on seamounts along the California Margin (CM) are influenced by terrestrial and biogenic input. These continental margin crusts have higher concentrations of Si, K, Fe, Na, Ag, Cr, B, and Ba than Fe-Mn crusts from the global open-ocean. Al is also higher but only relative to Pacific open-ocean crusts. These relative enrichments may reflect the high primary productivity near the CM caused by seasonal upwelling and high sediment transport to the region from river/eolian input and cliff erosion. Two transects with samples from five seamounts each are used to compare seaward changes. Transect A includes analyses of 66 bulk samples from Flint, Ben, and Little Joe seamounts, Patton Escarpment, and Northeast Bank. It spans ~400 km of seafloor heading ~58N and coming within ~220 km of the shoreline with samples collected at water depths ranging from 570-2925 m. Transect B includes analyses of 136 bulk samples from Adam, Hoss, San Marcos, San Juan, and Rodriguez seamounts at water depths ranging from 692-3880 m. This transect spans ~240 km heading ~10N and comes within ~75 km of the shoreline near the base of the continental slope. For both transects, mean water depth increases with mean longitude, and latitude is fairly constant varying by approximately 2 degree latitude for transect A and 1degree for B. Both transects show statistically significant trends at the 99% confidence level for element concentrations versus water depth. Concentrations of Fe, Ca, P, Co, and Pb increase as water depth decreases. For transect (A), Mn and Mg also follow this trend, as do Mo and Al for transect (B); Mn also shows this trend for transect (B) but at the 95% confidence level. For both transects, Cu and Zn show the opposite trend, with concentrations increasing in crusts with increasing water depth. For Transect (B), Ni and Al also show this trend. Si and K show no statistically significant trends for either transect. In open-ocean samples concentrations of Si generally increase in crusts with increasing water depth. The Si/Al ratio for the CM samples is 6.2 for transect (A) and 6.1 for (B). Global open-ocean crusts have a Si/Al ratio averaging about 4. This variation in CM crusts is due to input of biogenic Si; the ratio for terrestrial input would be much lower as concentrations of Al would be relatively higher. In global open-ocean samples Ca, Co, Mn, and P increase as water depth decreases while Cu and Fe increase as water depth increases. Element concentrations are influenced by the OMZ and by the chemical cycle of elements in the water column, including whether depth profiles are conservative, scavenged, or biologic. Element trends in CM Fe-Mn crusts can therefore be explained by high biological productivity, proximity to the OMZ, element profiles in the water column, and input of terrigenous debris.

  8. A new species of Haliotis (Gastropoda) from São Tomé & Príncipe Islands, Gulf of Guinea, with comparisons to other Haliotis found in the Eastern Atlantic and Mediterranean.

    PubMed

    Owen, Buzz

    2014-01-01

    The Haliotidae from the Gulf of Guinea, West Africa are reviewed. The distribution of the mainland species Haliotis marmorata Linnaeus, 1758 is confirmed and compared to the insular species from the island nation of São Tomé and Príncipe which is described as Haliotis geigeri n. sp. Both species are illustrated and compared to the other known Haliotidae from the eastern Atlantic. PMID:25081762

  9. Multiple forms of octopine dehydrogenase in Strombus luhuanus (mollusca, gastropoda, strombidae): genetic basis of polymorphism, properties of the enzymes, and relationship between the octopine dehydrogenase phenotype and the accumulation of anaerobic end products during exercise.

    PubMed

    Baldwin, J; England, W R

    1982-10-01

    Octopine dehydrogenase (ODH) is electrophoretically polymorphic in the gastropod mollusk Strombus luhuanus. The frequencies of the six electrophoretic phenotypes in the Heron Island population, together with the molecular weight values of 38,000 obtained for each of the three forms of the enzyme, demonstrate that the monomeric enzyme is encoded by three codominant alleles at a single locus. The purified allozymes are indistinguishable in terms of Km values for substrates, product inhibition by octopine and NAD, pH optima, and substrate inhibition by pyruvate. No statistically significant correlations were found between the ODH phenotype and the maximum activities of ODH or alanopine dehydrogenase, the capacity for anaerobic muscle work, or the accumulation of octopine or strombine/alanopine during exercise. It would appear that the ODH allozymes may be functionally equivalent both in vitro and in vivo. PMID:7181845

  10. Revision of the dwarf cannibal snails (Nata s.l.) of southern Africa-Nata s.s. and Natella (Mollusca: Gastropoda: Rhytididae), with description of three new species.

    PubMed

    Herbert, David G; Moussalli, Adnan

    2016-01-01

    This paper represents the second part of our revisionary studies on the rhytidid fauna of southern Africa. The species discussed belong to the taxon Nata s.l. in which we recognise two genus-level lineages, Nata s.s. and Natella with six (three new) and one species respectively. We update the species-level taxonomy extensively in the light of new molecular and morphological data, and provide a comprehensive revision of all species, including keys. Detailed comparative morphological observations are provided for the distal reproductive tract, pulmonary cavity, mantle edge, radula and suprapedal gland. In addition, we present a summary of biological and ecological data including information on habitat preferences, feeding, prey items and mating behaviour. Although the two genera are well circumscribed in terms of both internal anatomy and molecular data, shell morphology is highly conserved, and species discrimination using shell characters alone is difficult. We have discovered three undescribed species within Nata and there is evidence that further research of a phylogeographic nature may uncover additional cryptic diversity. The geographic distributions of the species are discussed in relation to regional vegetation patterns and, as with the larger cannibal snail radiation, the Albany Thicket Biome emerges as a focus of endemism. Observations on the conservation status of all species are provided.New species: Nata aequiplicata sp. nov., Nata erugata sp. nov. and Nata watsoni sp. nov. Revised status: Natalina caffrula Melvill & Ponsonby, 1898 is transferred to the genus Nata and thought to be a synonym of Nata dumeticola (Benson, 1851). PMID:27394520

  11. A snail in the long tail: a new Plekocheilus species collected by the ‘Comisión Científica del Pacífico’ (Mollusca, Gastropoda, Amphibulimidae)

    PubMed Central

    Breure, Abraham S. H.; Araujo, Rafael

    2015-01-01

    Abstract Among the historical collection gathered by the ‘Comisión Científica del Pacífico’ during 1862–1865, type material was found of one of the species described on the basis of the material collected shortly afterwards. Inspection of the types revealed that only one specimen may be considered as type material of Bulimus aristaceus Crosse, 1869; this specimen is now designated as the lectotype. The other specimens are described as a new species, Plekocheilus (Plekocheilus) cecepeus. PMID:26312021

  12. Revision of the dwarf cannibal snails (Nata s.l.) of southern Africa-Nata s.s. and Natella (Mollusca: Gastropoda: Rhytididae), with description of three new species.

    PubMed

    Herbert, David G; Moussalli, Adnan

    2016-01-01

    This paper represents the second part of our revisionary studies on the rhytidid fauna of southern Africa. The species discussed belong to the taxon Nata s.l. in which we recognise two genus-level lineages, Nata s.s. and Natella with six (three new) and one species respectively. We update the species-level taxonomy extensively in the light of new molecular and morphological data, and provide a comprehensive revision of all species, including keys. Detailed comparative morphological observations are provided for the distal reproductive tract, pulmonary cavity, mantle edge, radula and suprapedal gland. In addition, we present a summary of biological and ecological data including information on habitat preferences, feeding, prey items and mating behaviour. Although the two genera are well circumscribed in terms of both internal anatomy and molecular data, shell morphology is highly conserved, and species discrimination using shell characters alone is difficult. We have discovered three undescribed species within Nata and there is evidence that further research of a phylogeographic nature may uncover additional cryptic diversity. The geographic distributions of the species are discussed in relation to regional vegetation patterns and, as with the larger cannibal snail radiation, the Albany Thicket Biome emerges as a focus of endemism. Observations on the conservation status of all species are provided.New species: Nata aequiplicata sp. nov., Nata erugata sp. nov. and Nata watsoni sp. nov. Revised status: Natalina caffrula Melvill & Ponsonby, 1898 is transferred to the genus Nata and thought to be a synonym of Nata dumeticola (Benson, 1851).

  13. 77 FR 17478 - Change in Bank Control Notices; Acquisitions of Shares of a Bank or Bank Holding Company

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-26

    ..., Samuel C. Johnson III, Odinn R. Johnson, Olivia S. Johnson, Conrad W. Leipold, Samuel C. Leipold, Michael D. Marquart, Samantha G. Marquart, and Isabelle C. Marquart, as trustee or shareholder for...

  14. Analysis of wind tunnel test results for a 9.39-per cent scale model of a VSTOL fighter/attack aircraft. Volume 3: Effects of configuration variations from baseline

    NASA Technical Reports Server (NTRS)

    Lummus, J. R.; Joyce, G. T.; Omalley, C. D.

    1980-01-01

    The aerodynamic characteristics of the components of the baseline E205 configuration is presented. Geometric variations from the baseline E205 configuration are also given including a matrix of conrad longitudinal locations and strake shapes.

  15. Bean with Tools on the Ocean of Storms

    NASA Technical Reports Server (NTRS)

    1969-01-01

    Astronaut Alan L. Bean, Lunar Module pilot, pauses near a tool carrier during extravehicular activity (EVA) on the Moon's surface. Commander Charles Conrad Jr., who took the black and white photo, is reflected in Bean's helmet visor.

  16. 5. Historic American Buildings Survey, Arthur W. Stewart, Photographer June ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Historic American Buildings Survey, Arthur W. Stewart, Photographer June 26, 1936 DETAIL OF PORCH (NORTH ELEVATION). - Conrad Meuly House & Store, 210 Chaparral Street, Corpus Christi, Nueces County, TX

  17. 6. Historic American Buildings Survey, Arthur W. Stewart, Photographer October ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Historic American Buildings Survey, Arthur W. Stewart, Photographer October 10, 1936 DETAIL OF CAST IRON GRILLE ON FRONT PORCH. - Conrad Meuly House & Store, 210 Chaparral Street, Corpus Christi, Nueces County, TX

  18. 4. Historic American Buildings Survey, Arthur W. Stewart, Photographer June ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey, Arthur W. Stewart, Photographer June 26, 1936 GENERAL VIEW (NORTH AND EAST ELEVATION). - Conrad Meuly House & Store, 210 Chaparral Street, Corpus Christi, Nueces County, TX

  19. Too Little too Soon: The Literature of Deaf Education in 17th-Century Britain (Part II).

    ERIC Educational Resources Information Center

    Hoolihan, Christopher

    1985-01-01

    The article describes the growth in literature on deaf education in 17th century Britain. Noted is the work of John Wallis, William Holder, George Dalgarno, Anton Deusing, and Johann Conrad Amman. (CL)

  20. 8. Historic American Buildings Survey, Arthur W. Stewart, Photographer June ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Historic American Buildings Survey, Arthur W. Stewart, Photographer June 26, 1936 GENERAL VIEW AFTER 1919 STORM (SOUTHWEST ELEVATION). - Conrad Meuly House & Store, 210 Chaparral Street, Corpus Christi, Nueces County, TX

  1. 7. Historic American Buildings Survey, Arthur W. Stewart, Photographer June ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Historic American Buildings Survey, Arthur W. Stewart, Photographer June 26, 1936 GENERAL VIEW PRIOR TO 1919 STORM (EAST ELEVATION). - Conrad Meuly House & Store, 210 Chaparral Street, Corpus Christi, Nueces County, TX

  2. Artist concept of astronaut attempting to free solar array on Skylab

    NASA Technical Reports Server (NTRS)

    1973-01-01

    An artist's concept showing astronaut Charles Conrad Jr., Skylab 2 commander, attempting to free the solar array system wing on the Orbital Workshop during extravehicular activity at the Skylab 1 and 2 space station cluster in earth orbit. The astronaut in the background is Joseph P. Kerwin, Skylab 2 science pilot. Here, Conrad is pushing up on the Beam Erection Tether (BET) to raise the stuck solar panel.

  3. New porcellioidean gastropods from early Devonian of Royal Creek area, Yukon Territory, Canada, with notes on their early phylogeny

    USGS Publications Warehouse

    Fryda, J.; Blodgett, R.B.; Lenz, A.C.; Manda, S.

    2008-01-01

    This paper presents a description of new gastropods belonging to the superfamily Porcellioidea (Vetigastropoda) from the richly diverse Lower Devonian gastropod fauna of the Road River Formation in the Royal Creek area, Yukon Territory. This fauna belongs to Western Canada Province of the Old World Realm. The Pragian species Porcellia (Porcellia) yukonensis n. sp. and Porcellia (Paraporcellia) sp. represent the oldest presently known members of subgenera Porcellia (Porcellia) and Porcellia (Paraporcellia). Their simple shell ornamentation fits well with an earlier described evolutionary trend in shell morphology of the Porcellinae. Late Pragian to early Emsian Perryconcha pulchra n. gen. and n. sp. is the first member of the Porcellioidea bearing a row of tremata on adult teleoconch whorls. The occurrence of this shell feature in the Porcellioidea is additional evidence that the evolution of the apertural slit was much more complicated than has been proposed in classical models of Paleozoic gastropod evolution. Copyright ?? 2008, The Paleontological Society.

  4. Identification of Genes Related to Learning and Memory in the Brain Transcriptome of the Mollusc, "Hermissenda Crassicornis"

    ERIC Educational Resources Information Center

    Tamvacakis, Arianna N.; Senatore, Adriano; Katz, Paul S.

    2015-01-01

    The sea slug "Hermissenda crassicornis" (Mollusca, Gastropoda, Nudibranchia) has been studied extensively in associative learning paradigms. However, lack of genetic information previously hindered molecular-level investigations. Here, the "Hermissenda" brain transcriptome was sequenced and assembled de novo, producing 165,743…

  5. Neostusakia, a new name for preoccupied Stusakia Kment and Henry, 2008 (Hemiptera: Heteroptera: Berytidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A case of homonymy in the heteropteran family Berytidae is addressed. The genus Stusakia Kment and Henry, 2008 (Hemiptera) is preoccupied by Stusakia Frýda, 1998 (Mollusca: Gastropoda). As a consequence, the replacement name Neostusakia, new name, is proposed. In addition, the only two included s...

  6. Overland Flow Generation and Soil Hydraulic Properties in Two Catchments in Central Panama

    NASA Astrophysics Data System (ADS)

    Godsey, S.; Elsenbeer, H.; Stallard, R.

    2003-12-01

    Land management decisions in the Panama Canal watershed directly impact the hydrological functioning of the canal itself. Knowledge of the hydrological conditions in the forested portions of the watershed provides a baseline comparison for future land use changes. We chose to work on two streams on Barro Colorado Island that are representative of large regions of the watershed. These two streams respond differently to the same storm events: Conrad Trail Stream exhibits a fairly subdued and delayed response and Lutz Creek stream is flashier. In order to understand these differences, we investigated the soil saturated hydraulic conductivity (Ks) of the two catchments and studied the frequency of overland flow generation. The Ks measurements in dominant geologies in Lutz Creek as well as in Conrad Trail Stream are great enough at shallow depths (median Ks = 29.7, 65.6 and 38.3 mm/hr) that Hortonian overland flow is rare, but a marked decrease in Ks in Lutz Creek catchment at 30 cm (to 1.4 and 5.8 mm/hr) indicates that a perched water table leading to saturated overland flow is the likely runoff mechanism in Lutz Creek. In Conrad, Ks does not decrease as markedly with soil depth, and a perched water table would form at about 60 cm below the surface (median Ks = 0.7 mm/hr). Therefore, more water is able to infiltrate into the soil in Conrad Trail Stream and saturated overland flow is less common. Overland flow was generated much more frequently in Lutz Creek than in Conrad Trail Stream, with lower thresholds of storm magnitude, duration, antecedent wetness and intensity required to generate overland flow. We also quantified the importance of microtopographic features such as concentrated flow lines and the results have implications for experimental design at other field sites. The Lutz Creek and Conrad Trail stream information will provide a useful baseline for land management decisions.

  7. Magnetic Anomalies in the Enderby Basin, the Southern Indian Ocean

    NASA Astrophysics Data System (ADS)

    Nogi, Y.; Sato, T.; Hanyu, T.

    2013-12-01

    Magnetic anomalies in the Southern indian Ocean are vital to understanding initial breakup process of Gondwana. However, seafloor age estimated from magnetic anomalies still remain less well-defined because of the sparse observations in this area. To understand the seafloor spreading history related to the initial breakup process of Gondwana, vector magnetic anomaly data as well as total intensity magnetic anomaly data obtained by the R/V Hakuho-maru and the icebreaker Shirase in the Enderby Basin, Southern Indian Ocean, are used. The strikes of magnetic structures are deduced from the vector magnetic anomalies. Magnetic anomaly signals, most likely indicating Mesozoic magnetic anomaly sequence, are obtained almost parallel to the west of WNW-ESE trending lineaments just to the south of Conrad Rise inferred from satellite gravity anomalies. Most of the strikes of magnetic structures indicate NNE-SSW trends, and are almost perpendicular to the WNW-ESE trending lineaments. Mesozoic sequence magnetic anomalies with mostly WNW-ESE strikes are also observed along the NNE-SSW trending lineaments between the south of the Conrad Rise and Gunnerus Ridge. Magnetic anomalies originated from Cretaceous normal polarity superchron are found in these profiles, although magnetic anomaly C34 has been identified just to the north of the Conrad Rise. However Mesozoic sequence magnetic anomalies are only observed in the west side of the WNW-ESE trending lineaments just to the south of Conrad Rise and not detected to the east of Cretaceous normal superchron signals. These results show that counter part of Mesozoic sequence magnetic anomalies in the south of Conrad Rise would be found in the East Enderby Basin, off East Antarctica. NNE-SSW trending magnetic structures, which are similar to those obtained just to the south of Conrad Rise, are found off East Antarctica in the East Enderby Basin. However, some of the strikes show almost E-W orientations. These suggest complicated ridge

  8. The problems associated with the monitoring of complex workplace radiation fields at European high-energy accelerators and thermonuclear fusion facilities.

    PubMed

    Bilski, P; Blomgren, J; d'Errico, F; Esposito, A; Fehrenbacher, G; Fernàndez, F; Fuchs, A; Golnik, N; Lacoste, V; Leuschner, A; Sandri, S; Silari, M; Spurny, F; Wiegel, B; Wright, P

    2007-01-01

    The European Commission is funding within its Sixth Framework Programme a three-year project (2005-2007) called CONRAD, COordinated Network for RAdiation Dosimetry. The organisational framework for this project is provided by the European Radiation Dosimetry Group EURADOS. One task within the CONRAD project, Work Package 6 (WP6), was to provide a report outlining research needs and research activities within Europe to develop new and improved methods and techniques for the characterisation of complex radiation fields at workplaces around high-energy accelerators, but also at the next generation of thermonuclear fusion facilities. The paper provides an overview of the report, which will be available as CERN Yellow Report.

  9. Recherches en phonetique et en phonologie au Quebec (Research in Phonetics and Phonology in Quebec). Publication B-206.

    ERIC Educational Resources Information Center

    Dolbec, Jean, Ed.; Ouellet, Marise, Ed.

    The collection of essays on phonetics and phonology, entirely in French, includes: "Le calcul de la frequence intrinseque. Necessite du rapport a une ligne de reference" (calculation of intrinsic frequency; necessity of a line of reference) (Conrad Ouellon); "Caracteristiques microprosodiques de duree et d'intensite en lecture et en conversation…

  10. Multifaceted Approach to Designing an Online Masters Program.

    ERIC Educational Resources Information Center

    McNeil, Sara G.; Chernish, William N.; DeFranco, Agnes L.

    At the Conrad N. Hilton College of Hotel and Restaurant Management at the University of Houston (Texas), the faculty and administrators made a conscious effort to take a broad, extensive approach to designing and implementing a fully online masters program. This approach was entered in a comprehensive needs assessment model and sought input from…

  11. Secret-Sharing in the Introductory Literature Class.

    ERIC Educational Resources Information Center

    Walker, Ronald G.

    2000-01-01

    Considers how seeking "hidden meanings," attending to the language in which they are embedded, and sharing that experience with students seems to be a viable way to conceive of the essence of literary study. Describes a writing assignment (a "documented critical paper") based on Joseph Conrad's "Secret Sharer." (SG)

  12. Milestones in the Secondary English Curriculum in the United States. ICTE Occasional Paper No. 11.

    ERIC Educational Resources Information Center

    Bleakley, Lou Ann

    Written for students pursuing graduate study, this chronological table lists landmark publications in the secondary English curriculum occurring between 1893 and 1971. For each of the 27 milestones--e.g., "Report of the Committee of Ten on Secondary School Studies" (1893), "Teaching Creative Writing" by Lawrence Conrad (1937), "The Uses of…

  13. Engagement in Two Interdisciplinary Graduate Programs

    ERIC Educational Resources Information Center

    Newswander, Lynita K.; Borrego, Maura

    2009-01-01

    This qualitative study examines two US interdisciplinary graduate programs which involve faculty and students from different disciplines. Haworth and Conrad's engagement theory of quality graduate education was applied. It was found that when interdisciplinary programs facilitate engagement by supporting diversity, participation, connections, and…

  14. Henry James: A Collection of Critical Essays. Twentieth Century Views Series.

    ERIC Educational Resources Information Center

    Edel, Leon, Ed.

    One of a series of works aimed at presenting contemporary critical opinion on major authors, this collection includes essays by Leon Edel, Joseph Conrad, Max Beerbohm, Ezra Pound, Edith Wharton, Percy Lubbock, Virginia Woolf, T. S. Eliot, Van Wyck Brooks, Edmund Wilson, E. M. Forster, William Troy, Pelham Edgar, Stephen Spender, Graham Greene,…

  15. An Investigation of Language Teachers' Explorations of the Use of Corpus Tools in the English for Academic Purposes (EAP) Class

    ERIC Educational Resources Information Center

    Bunting, John David

    2013-01-01

    Despite claims that the use of corpus tools can have a major impact in language classrooms (e.g., Conrad, 2000, 2004; Davies, 2004; O'Keefe, McCarthy, & Carter, 2007; Sinclair, 2004b; Tsui, 2004), many language teachers express apparent apathy or even resistance towards adding corpus tools to their repertoire (Cortes, 2013b). This study…

  16. When Good Gifts Go Bad

    ERIC Educational Resources Information Center

    Strout, Erin

    2006-01-01

    Conrad Colbrandt gave Saint Mary's College of California a financial permission slip to dream big--a $112-million pledge to support new construction and endowments. From the time that Colbrandt made his pledge in 1997 until 2004, talk of new athletics facilities and classroom buildings became real architectural plans. However, all of those plans…

  17. Centennial of Röntgen's discovery of x-rays.

    PubMed Central

    Frankel, R I

    1996-01-01

    November 8, 1995, marked the 100th anniversary of Wilhelm Conrad Röntgen's discovery of x-rays. This remarkable scientific achievement has had an effect on medicine and science that has been matched by few other advances. I will briefly review the events leading up to Röntgen's discovery and the subsequent development of radiology as a discipline. PMID:8764624

  18. "The Mirror of the Sea": Narrative Identity, Sea Kayak Adventuring and Implications for Outdoor Adventure Education

    ERIC Educational Resources Information Center

    Miles, Beau; Wattchow, Brian

    2015-01-01

    This paper explores the complex and changing nature of adventure as a form of cultural practice. Borrowing from Joseph Conrad's memoirs "The Mirror of The Sea" (1907), sea kayaking is contextualized here as a journey that takes place just as much between "landfall and departure" as it does between the paddler's ears (i.e., in…

  19. Success of Breast Cancer Startup Challenge Inspires Second Challenge | Poster

    Cancer.gov

    By Thomas Stackhouse, Joseph Conrad, and Michele Newton, Contributing Writers, and Rosemarie Truman, Guest Writer Sixty-one teams have been accepted into, and are now competing in, the Neuro Startup Challenge, a new collaboration established by the National Institutes of Health (NIH) with The Center for Advancing Innovation (CAI) and Heritage Provider Network, Inc.

  20. Art as science: scientific illustration, 1490-1670 in drawing, woodcut and copper plate.

    PubMed

    Pyle, C M

    2000-01-01

    Observation, depiction and description are active forces in the doing of science. Advances in observation and analysis come with advances in techniques of description and communication. In this article, these questions are related to the work of Leonardo da Vinci, 16th-century naturalists and artists like Conrad Gessner and Teodoro Ghisi, and 17th-century micrographers like Robert Hooke.

  1. Lexical Bundle Analysis in Mathematics Classroom Discourse: The Significance of Stance

    ERIC Educational Resources Information Center

    Herbel-Eisenmann, Beth; Wagner, David; Cortes, Viviana

    2010-01-01

    In this article, we introduce the lexical bundle, defined by corpus linguists as a group of three or more words that frequently recur together, in a single group, in a particular register (Biber, Johansson, Leech, Conrad, & Finegan, 2006; Cortes, "English for Specific Purposes" 23:397-423, 2004). Attention to lexical bundles helps to explore…

  2. The Most Frequently Used English Phrasal Verbs in American and British English: A Multicorpus Examination

    ERIC Educational Resources Information Center

    Liu, Dilin

    2011-01-01

    This study uses the Corpus of Contemporary American English and the British National Corpus as data and Biber, Johansson, Leech, Conrad, and Finegan's (1999) and Gardner and Davies' (2007) informative studies as a starting point and reference. The study offers a cross-English variety and cross-register examination of the use of English phrasal…

  3. RESISTIVITY METHODS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Resistivity methods were among the first geophysical techniques developed. The basic concept originated with Conrad Schlumberger, who conducted the initial resistivity field tests in Normandy, France during 1912. The resistivity method, employed in its earliest and most conventional form, uses an ex...

  4. Hearing on Telecommunications Policy Reform. Hearing of the Committee on Commerce, Science, and Transportation. United States Senate, One Hundred Fourth Congress, First Session.

    ERIC Educational Resources Information Center

    Congress of the U.S., Washington, DC. Senate Committee on Commerce, Science, and Transportation.

    This document presents witness testimony and supplemental materials from a Congressional hearing regarding reform to national telecommunications policy, namely, replacing a regime of heavy regulation with a true market system. Statements are featured by Senators John Ashcroft, Conrad Burns, Ernest Hollings, Kay Baily Hutchison, John D. Rockefeller…

  5. Astronaut Alan Bean holds Special Environmental Sample Container

    NASA Technical Reports Server (NTRS)

    1969-01-01

    Astronaut Alan L. Bean, lunar module pilot for the Apollo 12 lunar landing mission, holds a Special Environmental Sample Container filled with lunar soil collected during the extravehicular activity (EVA) in which Astronauts Charles Conrad Jr., commander, and Bean participated. Connrad, who took this picture, is reflected in the helmet visor of the lunar module pilot.

  6. Astronaut Alan Bean deploys ALSEP during first Apollo 12 EVA on moon

    NASA Technical Reports Server (NTRS)

    1969-01-01

    Astronaut Alan L. Bean, Apollo 12 lunar module pilot, deploys components of the Apollo Lunar Surface Experiments Package (ALSEP) during the first Apollo 12 extravehicular activity (EVA) on the moon. The photo was made by Astronaut Charles Conrad Jr., Apollo 12 commander, using a 70mm handheld Haselblad camera modified for lunar surface usage.

  7. Astronaut Alan Bean steps from ladder of Lunar Module for EVA

    NASA Technical Reports Server (NTRS)

    1969-01-01

    Astronaut Alan L. Bean, lunar module pilot for the Apollo 12 lunar landing mission, steps from the ladder of the Lunar Module to join Astronaut Charles Conrad Jr., commander, in extravehicular activity on November 19, 1969. Astronaut Ricard F. Gordon Jr., command module pilot, remained with the Command/Service Modules in lunar orbit.

  8. Bean Samples The Ocean of Storms

    NASA Technical Reports Server (NTRS)

    1969-01-01

    Astronaut Alan L. Bean, Lunar Module pilot for the Apollo 12 lunar landing mission, holds a Special Environmental Sample Container filled with lunar soil collected during the extravehicular activity (EVA) in which Astronauts Charles Conrad Jr., commander, and Bean participated. Connrad, who took this picture, is reflected in the helmet visor of the Lunar Module pilot.

  9. The National Women's Leadership Conference on Fitness. Proceedings. (Washington, D.C., April 6-7, 1984).

    ERIC Educational Resources Information Center

    President's Council on Physical Fitness and Sports, Washington, DC.

    The principal addresses at this Women's Leadership Conference on Fitness were: (1) "Keynote Address" (C. Carson Conrad); (2) "Essential Nature of Fitness" (Lawrence E. Lamb); (3) "Effects of Exercise on Women from 20-50 Years Old" (Sharon Plowman); (4) "Fitness in Older Women" (Everett L. Smith); (5) "Female Musculo-Skeletal System" (Robert P.…

  10. Cultivating Inquiry-Driven Learners: A College Education for the Twenty-First Century

    ERIC Educational Resources Information Center

    Conrad, Clifton; Dunek, Laura

    2012-01-01

    Inquiry-driven learners anticipate, embrace, and adapt to disruptive change. Clifton Conrad and Laura Dunek advance a transformative purpose of a college education. They invite stakeholders from across higher education to engage in vigorous dialogue about the aims of a college education--and how to realize those aims. Increasingly influenced by…

  11. Radiation in the universe

    NASA Technical Reports Server (NTRS)

    Stuhlinger, Ernst; Truemper, Joachim; Weisskopf, Martin

    1992-01-01

    When Wilhelm Conrad Roentgen discovered radiation one hundred years ago, it seemed that what was discovered was one of the rarest and most volatile members of the family of the basic modules of our natural world. Today cosmologists report that a substantial part of the universe's radiation energy consists of X-rays, which travel through cosmic space with the speed of light.

  12. Art as science: scientific illustration, 1490-1670 in drawing, woodcut and copper plate.

    PubMed

    Pyle, C M

    2000-01-01

    Observation, depiction and description are active forces in the doing of science. Advances in observation and analysis come with advances in techniques of description and communication. In this article, these questions are related to the work of Leonardo da Vinci, 16th-century naturalists and artists like Conrad Gessner and Teodoro Ghisi, and 17th-century micrographers like Robert Hooke. PMID:10969482

  13. Test Bias in the Absence of a Criterion.

    ERIC Educational Resources Information Center

    Echternacht, Gary

    This paper proposes a method of transforming item p-values (the proportion answering a test item correctly) to what are termed "delta" values. First used by Conrad in l948, deltas are routine statistics computed in all analyses at Educational Testing Service. Using this approach one would conclude no test bias if differences in resulting deltas…

  14. The secret sharer as a guide to compassion.

    PubMed

    Young-Mason, J

    1991-01-01

    Joseph Conrad's novella demonstrates the ways in which over-identification with a stranger influences and clouds the critical judgment of a young professional. It provides rich material for discussion on the caution needed by young nurses to make decisions based on critical judgment and not personal feelings.

  15. Preparing Technicians for the Twenty-First Century in Agriculture, Agribusiness, and Natural Resources. Summary Report of a Conference (Columbus, Ohio, April 15-16, 1985).

    ERIC Educational Resources Information Center

    Mokma, Arnold L., Ed.; Barrick, Kirby, Ed.

    This report contains summaries of various portions of a conference dealing with preparing technicians for various agricultural occupations as well as the texts of several papers presented at the conference. The keynote address, "Technology for the 21st Century" by John A. Conrads, is presented together with the following reaction panel papers:…

  16. Testing the Engagement Theory of Program Quality in CACREP-Accredited Counselor Education Programs

    ERIC Educational Resources Information Center

    Warden, Shannon P.; Benshoff, James M.

    2012-01-01

    This study examined the engagement theory of program quality (Haworth & Conrad, 1997), which highlights positive student learning outcomes that result from stakeholder involvement in program evaluation within master's-level graduate programs. A total of 481 master's-level counseling students and 63 faculty members, representing 68 Council for…

  17. Reauthorization of the Tribally Controlled Community College Assistance Act of 1978. Hearing on S. 2167 To Reauthorize the Tribally Controlled College Assistance Act of 1978 and the Navajo Community College Act [and on] S. 2213 To Increase the Federal Contribution to the Tribally Controlled Community College Endowment Program, before the Select Committee on Indian Affairs, United States Senate, One Hundred First Congress, Second Session (Bismarck, North Dakota, April 9, 1990).

    ERIC Educational Resources Information Center

    Congress of the U.S., Washington, DC. Senate Select Committee on Indian Affairs.

    Testimony on two bills dealing with federal funding for American Indian tribally controlled colleges is reported. Introduced by Senator John McCain (Arizona), S. 2167 seeks to reauthorize the Tribally Controlled Community College Assistance Act of 1978 and the Navajo Community College Act. Introduced by Senator Kent Conrad (North Dakota), S. 2213…

  18. Research in Correctional Rehabilitation.

    ERIC Educational Resources Information Center

    Rehabilitation Services Administration (DHEW), Washington, DC.

    Forty-three leaders in corrections and rehabilitation participated in the seminar planned to provide an indication of the status of research in correctional rehabilitation. Papers include: (1) "Program Trends in Correctional Rehabilitation" by John P. Conrad, (2) "Federal Offenders Rahabilitation Program" by Percy B. Bell and Merlyn Mathews, (3)…

  19. LBNL deliverable to the Tricarb carbon sequestration partnership: Final report on experimental and numerical modeling activities for the Newark Basin

    SciTech Connect

    Mukhopadhyay, Sumit; Spycher, Nicolas; Pester, Nick; Saldi, Giuseppe; Beyer, John; Houseworth, Jim; Knauss, Kevin

    2014-09-04

    This report presents findings for hydrological and chemical characteristics and processes relevant to large-scale geologic CO2 sequestration in the Newark Basin of southern New York and northern New Jersey. This work has been conducted in collaboration with the Tri-Carb Consortium for Carbon Sequestration — comprising Sandia Technologies, LLC; Conrad Geoscience; and Schlumberger Carbon Services.

  20. The secret sharer as a guide to compassion.

    PubMed

    Young-Mason, J

    1991-01-01

    Joseph Conrad's novella demonstrates the ways in which over-identification with a stranger influences and clouds the critical judgment of a young professional. It provides rich material for discussion on the caution needed by young nurses to make decisions based on critical judgment and not personal feelings. PMID:1705323

  1. Two Views of Criminology and Criminal Justice: Definitions, Trends, and the Future.

    ERIC Educational Resources Information Center

    Conrad, John P.; Myren, Richard A.

    The question of whether criminology and criminal justice are distinct fields is addressed in two papers. Differences between criminology and criminal justice are delineated by emphasizing formal definitions of the field(s), occupational roles, contemporary educational trends, and future development. According to John P. Conrad, criminology is the…

  2. Emily Dickinson: A Collection of Critical Essays. Twentieth Century Views Series.

    ERIC Educational Resources Information Center

    Sewall, Richard B., Ed.

    One of a series of works aimed at presenting contemporary critical opinion on major authors, this collection includes essays by Richard B. Sewall, Conrad Aiken, Allen Tate, Yvor Winters, George F. Whicher, Henry W. Wells, Donald E. Thackrey, Thomas H. Johnson, R. P. Blackmur, John Crowe Ransom, Austin Warren, James Reeves, Richard Wilbur, Louise…

  3. Religion on Campus.

    ERIC Educational Resources Information Center

    Cherry, Conrad; DeBerg, Betty A.; Porterfield, Amanda

    Case studies at four colleges explored students religious studies, values, and practices. Observations and interviews show that both the practice and the study of religion are thriving and supported by campus cultures. The chapters are: (1) Introduction; (2) West University (Betty A. Deberg); (3) South University (Conrad Cherry); (4) East…

  4. A Framework for Interaction and Cognitive Engagement in Connectivist Learning Contexts

    ERIC Educational Resources Information Center

    Wang, Zhijun; Chen, Li; Anderson, Terry

    2014-01-01

    Interaction has always been highly valued in education, especially in distance education (Moore, 1989; Anderson, 2003; Chen, 2004a; Woo & Reeves, 2007; Wang, 2013; Conrad, in press). It has been associated with motivation (Mahle, 2011; Wen-chi, et al., 2011), persistence (Tello, 2007; Joo, Lim, & Kim, 2011), deep learning (Offir, et al.,…

  5. Gemini 8 prime and backup crews during press conference

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Gemini 8 prime and backup crews during press conference. Left to right are Astronauts David R. Scott, prime crew pilot; Neil A. Armstrong, prime crew command pilot; Charles Conrad Jr., backup crew command pilot; and Richard F. Gordon Jr., backup crew pilot.

  6. Gemini 11 prime and back-up crews at Gemini Mission Simulator at Cape Kennedy

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Gemini 11 prime and back-up crews at Gemini Mission Simulator at Cape Kennedy, Florida. Left to right are Astronauts William A. Anders, back-up crew pilot; Richard F. Gordon Jr., prime crew pilot; Charles Conrad Jr. (foot on desk), prime crew command pilot; and Neil A. Armstrong, back-up crew command pilot.

  7. Portrait of the Gemini 8 prime and backup crews

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Portrait of the Gemini 8 prime and backup crews. Astronauts David R. Scott (left), pilot, and Astronaut Neil A. Armstrong, command pilot, are the prime crew of the Gemini 8 mission. Backup crew (left to right, standing), are Astronauts Richard F. Gordon Jr., pilot, and Charles Conrad Jr., command pilot.

  8. Proceedings of the Annual Conference of the Canadian Association for the Study of Adult Education/L'Association Canadienne pour L'Etude de L'Education des Adultes (17th, Ontario, Canada, May 29-31, 1998).

    ERIC Educational Resources Information Center

    Taylor, Maurice, Ed.

    These proceedings on the theme, Adult Education Research: Shaping the Future, contain 52 papers. The papers are: "Virtual Adult Education" (W. Archer and D. Conrad); "Reversal Theory Approach to Adult Learning and Education" (M. Atleo); "Objectiver L'Action" (A. Balleux et al.); "Cultural Constructions of Literacy" (A. Blunt); "Prior Learning…

  9. Mental Retardation 1970: Selected Papers from the 94th Annual Meeting of the American Association on Mental Deficiency (Washington, D.C., May, 1970).

    ERIC Educational Resources Information Center

    Gardner, James M., Ed.

    Research papers on behavior modification, presented at the 94th annual meeting of the American Association on Mental Deficiency, are cited in Volume 2 of a two part series. Presentations by James Gardner, Maurice Dayan, Luke Watson, Robert Wahler, and Robert Conrad are given. Volume 1 (EC 031 272) deals with theoretical papers and complements…

  10. MICA, 1972-73. Outcome Evaluation Report.

    ERIC Educational Resources Information Center

    Koch, Richard R.

    The Mathematics Inquiry in the Conrad Area (MICA) Project had as its general focus the installation of a variety of teaching approaches, with emphases on open-ended units. The purpose was to give teachers exposure to the diversity of possible approaches, to use and test the effectiveness of the methods, and to familiarize other teachers with the…

  11. The History of Molecular Structure Determination Viewed through the Nobel Prizes.

    ERIC Educational Resources Information Center

    Jensen, William P.; Palenik, Gus J.; Suh, Il-Hwan

    2003-01-01

    Discusses the importance of complex molecular structures. Emphasizes their individual significance through examination of the Nobel Prizes of the 20th century. Highlights prizes awarded to Conrad Rontgen, Francis H.C. Crick, James D. Watson, Maurice H.F. Wilkins, and others. (SOE)

  12. Cultural Influences on Adult Learning.

    ERIC Educational Resources Information Center

    Conti, Gary J., Ed.; Fellenz, Robert A., Ed.

    Five projects are reported that examined factors related to adult learning in nontraditional environments. "Conrad, Montana: A Community of Memories" (Janice Counter, Lynn Paul, and Gary Conti) reports on a group of adults who for over 40 years have been active in building a better community for friends, relatives, and themselves. A 17-item…

  13. Strengthening At-Risk and Homeless Young Mothers and Children

    ERIC Educational Resources Information Center

    Medeiros, Debra; Vaulton, Wendy

    2010-01-01

    The Strengthening At Risk and Homeless Young Mothers and Children Initiative, funded by the Conrad N. Hilton Foundation, aims to improve the housing, health, and development of homeless and at-risk young families. This article describes the services provided in four program sites (Pomona, CA; Antelope Valley, CA; Minneapolis, MN; and Chicago, IL)…

  14. Rock sample brought to earth from the Apollo 12 lunar landing mission

    NASA Technical Reports Server (NTRS)

    1969-01-01

    Astronaut Charles Conrad Jr., commander of the Apollo 12 lunar landing mission, holds two lunar rocks which were among the samples brought back from the Moon by the Apollo 12 astronauts. The samples are under scientific examination in the Manned Spacecraft Center's Lunar Receiving Laboratory.

  15. Shut Out

    ERIC Educational Resources Information Center

    Roach, Ronald

    2009-01-01

    As director of the Lawyering in the Digital Age Clinic at the Columbia University Law School, law professor Conrad Johnson knows that digital technology has the power to highlight and amplify social justice concerns and to enable people to take direct action. Under Johnson's leadership, the clinic has developed and maintained the Columbia-hosted…

  16. Dissection of two soybean QTL conferring partial resistance to Phytophthora sojae through sequence and gene expression analysis

    PubMed Central

    2012-01-01

    Background Phytophthora sojae is the primary pathogen of soybeans that are grown on poorly drained soils. Race-specific resistance to P. sojae in soybean is gene-for-gene, although in many areas of the US and worldwide there are populations that have adapted to the most commonly deployed resistance to P. sojae ( Rps) genes. Hence, this system has received increased attention towards identifying mechanisms and molecular markers associated with partial resistance to this pathogen. Several quantitative trait loci (QTL) have been identified in the soybean cultivar ‘Conrad’ that contributes to the expression of partial resistance to multiple P. sojae isolates. Results In this study, two of the Conrad QTL on chromosome 19 were dissected through sequence and expression analysis of genes in both resistant (Conrad) and susceptible (‘Sloan’) genotypes. There were 1025 single nucleotide polymorphisms (SNPs) in 87 of 153 genes sequenced from Conrad and Sloan. There were 304 SNPs in 54 genes sequenced from Conrad compared to those from both Sloan and Williams 82, of which 11 genes had SNPs unique to Conrad. Eleven of 19 genes in these regions analyzed with qRT-PCR had significant differences in fold change of transcript abundance in response to infection with P. sojae in lines with QTL haplotype from the resistant parent compared to those with the susceptible parent haplotype. From these, 8 of the 11 genes had SNPs in the upstream, untranslated region, exon, intron, and/or downstream region. These 11 candidate genes encode proteins potentially involved in signal transduction, hormone-mediated pathways, plant cell structural modification, ubiquitination, and basal resistance. Conclusions These findings may indicate a complex defense network with multiple mechanisms underlying these two soybean QTL conferring resistance to P. sojae. SNP markers derived from these candidate genes can contribute to fine mapping of QTL and marker assisted breeding for resistance to P. sojae

  17. How are macroinvertebrates of slow flowing lotic systems directly affected by suspended and deposited sediments?

    PubMed

    Kefford, Ben J; Zalizniak, Liliana; Dunlop, Jason E; Nugegoda, Dayanthi; Choy, Satish C

    2010-02-01

    The effects of suspended and deposited sediments on the macroinvertebrates are well documented in upland streams but not in slower flowing lowland rivers. Using species found in lowland lotic environments, we experimentally evaluate mechanisms for sediments to affect macroinvertebrates, and in one experiment whether salinity alters the effect of suspended sediments. Suspended kaolin clay reduced feeding of Ischnura heterosticta (Odonata: Coenagrionidae) at high turbidity (1000-1500 NTU) but had no effects on feeding of Hemianax papuensis (Odonata: Aeshnidae) and Micronecta australiensis (Hemiptera: Corixidae). In freshwater (0.1 mS/cm), survival of Ischnura aurora was poor in clear water, but improved with suspended kaolin. Growth and feeding of I. aurora were unaffected by suspended sediments and salinity. Burial (1-5 mm) of eggs with kaolin or sand reduced hatching in Physa acuta (Gastropoda: Physidae), Gyraulus tasmanica (Gastropoda: Planorbidae) and Chironomus cloacalis (Diptera: Chironomidae). Settling sediments may pose greater risk to lowland lotic invertebrates than suspended sediments.

  18. Complete mitochondrial genome of Pacific abalone (Haliotis discus hannai) from Korea.

    PubMed

    Yang, Eun Chan; Nam, Bo-Hye; Noh, Seung-Jae; Kim, Young-Ok; Kim, Dong-Gyun; Jee, Young Ju; Park, Jun-Hyung; Noh, Jae Hoon; Yoon, Hwan Su

    2015-01-01

    We have sequenced and characterized the complete mitochondrial DNA of an economically and ecologically important Pacific abalone, Haliotis discus hannai (Haliotidae, Gastropoda). The mitogenome of the Pacific abalone is 16,886 nt total length with a 39.6% G+C composition. Thirty-seven genes were identified including 13 protein-coding, 2 rRNA and 22 tRNA genes. We compared the mitogenome of the Pacific abalone to a putative relative species, H. rubra.

  19. UV Light Reveals the Diversity of Jurassic Shell Colour Patterns: Examples from the Cordebugle Lagerstätte (Calvados, France)

    PubMed Central

    Caze, Bruno; Merle, Didier; Schneider, Simon

    2015-01-01

    Viewed under UV light the diverse and exceptionally well-preserved molluscs from the Late Jurassic Cordebugle Konservat Lagerstätte (Calvados, Normandy, France) reveal fluorescent fossil shell colour patterns predating the oldest previously known instance of such patterns by 100 Myr. Evidently, residual colour patterns are observable in Mesozoic molluscs by application of this non-destructive method, provided the shells are not decalcified or recrystallized. Among 46 species which are assigned to twelve gastropod families and eight bivalve families, no less than 25 species yielded positive results. Out of nine colour pattern morphologies that have been distinguished six occur in gastropods and three in bivalves. The presence of these variant morphologies clearly indicates a significant pre-Cenozoic diversification of colour patterns, especially in gastropods. In addition, the occurrence of two distinct types of fluorescence highlights a major difference in the chemical composition of the pigments involved in colour pattern formation in gastropods. This discovery enables us to discriminate members of higher clades, i.e. the Vetigastropoda emitting red fluorescence from the Caenogastropoda and Heterobranchia emitting whitish-beige to yellow fluorescence. Consequently, fluorescent colour patterns may help to allocate part of the numerous enigmatic Mesozoic gastropod taxa to their correct systematic position. PMID:26039592

  20. Phylogenomic analyses of deep gastropod relationships reject Orthogastropoda

    PubMed Central

    Zapata, Felipe; Wilson, Nerida G.; Howison, Mark; Andrade, Sónia C. S.; Jörger, Katharina M.; Schrödl, Michael; Goetz, Freya E.; Giribet, Gonzalo; Dunn, Casey W.

    2014-01-01

    Gastropods are a highly diverse clade of molluscs that includes many familiar animals, such as limpets, snails, slugs and sea slugs. It is one of the most abundant groups of animals in the sea and the only molluscan lineage that has successfully colonized land. Yet the relationships among and within its constituent clades have remained in flux for over a century of morphological, anatomical and molecular study. Here, we re-evaluate gastropod phylogenetic relationships by collecting new transcriptome data for 40 species and analysing them in combination with publicly available genomes and transcriptomes. Our datasets include all five main gastropod clades: Patellogastropoda, Vetigastropoda, Neritimorpha, Caenogastropoda and Heterobranchia. We use two different methods to assign orthology, subsample each of these matrices into three increasingly dense subsets, and analyse all six of these supermatrices with two different models of molecular evolution. All 12 analyses yield the same unrooted network connecting the five major gastropod lineages. This reduces deep gastropod phylogeny to three alternative rooting hypotheses. These results reject the prevalent hypothesis of gastropod phylogeny, Orthogastropoda. Our dated tree is congruent with a possible end-Permian recovery of some gastropod clades, namely Caenogastropoda and some Heterobranchia subclades. PMID:25232139

  1. Phyletic patterns of early development in gastropod molluscs.

    PubMed

    Lindberg, David R; Guralnick, Robert P

    2003-01-01

    Cell lineage data for 30 exemplar gastropod taxa representing all major subclades and the outgroup Polyplacophora were examined for phylogenetic signal using cladistic analysis. Most cell lineages show phyletic trends of acceleration or retardation relative to the outgroup and more basal ingroup taxa, and when coded this variation is phylo-genetically informative. PAUP analyses of a cell lineage data set under three sets of character ordering assumptions produced similar tree topologies. The topologies of the strict consensus trees for both ordered and Dollo (near irreversibility of character transformations) character assumptions were similar, whereas the unordered character assumption recovers the least phyletic information. The cell lineage cladograms are also in agreement with the fossil record of the timing and sequence of gastropod subclade origination. A long branch lies between the Patellogastropoda+Vetigastropoda grade and the Neritopsina+Apogastropoda clade. The geological timing of this long branch is correlated with the first large-scale terrestrially derived eutrophication of the near-shore marine habitat, and one possible explanation for this branch may be a developmental shift associated with the evolution of feeding larvae in response to the more productive conditions in the near-shore water column. Although character transformations are highly ordered in this data set, developmental rate characters (like all other morphological and molecular characters) are also subject to homoplasy. Finally, this study further supports the hypothesis that early development of gastropod molluscs has conserved a strong phyletic signal for about half a billion years. PMID:12950628

  2. Mobile Element Evolution Playing Jigsaw—SINEs in Gastropod and Bivalve Mollusks

    PubMed Central

    Matetovici, Irina; Sajgo, Szilard; Ianc, Bianca; Ochis, Cornelia; Bulzu, Paul; Popescu, Octavian; Damert, Annette

    2016-01-01

    SINEs (Short INterspersed Elements) are widely distributed among eukaryotes. Some SINE families are organized in superfamilies characterized by a shared central domain. These central domains are conserved across species, classes, and even phyla. Here we report the identification of two novel such superfamilies in the genomes of gastropod and bivalve mollusks. The central conserved domain of the first superfamily is present in SINEs in Caenogastropoda and Vetigastropoda as well as in all four subclasses of Bivalvia. We designated the domain MESC (Romanian for MElc—snail and SCoica—mussel) because it appears to be restricted to snails and mussels. The second superfamily is restricted to Caenogastropoda. Its central conserved domain—Snail—is related to the Nin-DC domain. Furthermore, we provide evidence that a 40-bp subdomain of the SINE V-domain is conserved in SINEs in mollusks and arthropods. It is predicted to form a stable stem-loop structure that is preserved in the context of the overall SINE RNA secondary structure in invertebrates. Our analysis also recovered short retrotransposons with a Long INterspersed Element (LINE)-derived 5′ end. These share the body and/or the tail with transfer RNA (tRNA)-derived SINEs within and across species. Finally, we identified CORE SINEs in gastropods and bivalves—extending the distribution range of this superfamily. PMID:26739168

  3. Analysis of physical processes in ICF target chambers

    SciTech Connect

    MacFarlane, J.J.; Peterson, R.R.; Moses, G.A.

    1989-03-01

    When a high-gain inertial fusion target explodes, roughly one third of the energy is released in the form of x-rays and energetic ions, which can damage the wall of the chamber. One method of protecting the wall is to place a gas in the chamber cavity. The authors use a 1-D Lagrangian radiation-hydrodynamics code (CONRAD) to study the target energy deposition in this cavity gas and first surface material, the growth of and radiative emission from the microfireball, the expansion of the shock front, the vaporization and hydromotion of the first surface material, and the recondensation of that material back onto the wall. The authors describe recent improvements to CONRAD, and present results for two target chamber designs currently being considered by Lawrence Livermore National Laboratory for the Laboratory Microfusion Facility.

  4. Astronaut Alan Bean assisted with egressing command module after landing

    NASA Technical Reports Server (NTRS)

    1969-01-01

    Astronaut Alan L. Bean, lunar module pilot, is assisted with egressing the Apollo 12 Command Module by a U.S. Navy underwater demolition team swimmer during recovery operations in the Pacific Ocean. Already in the life raft are Astronauts Charles Conrad Jr., commander; and Richard F. Gordon Jr., command module pilot. The Apollo 12 splashdown occured at 2:58 p.m., November 24, 1969 near American Samoa.

  5. Seismometer reading from impact made by Lunar Module ascent stage

    NASA Technical Reports Server (NTRS)

    1969-01-01

    The seismometer reading from the impact made by the Lunar Module ascent stage when it struck the lunar surface. The impact was registered by the Passive Seismic Experiment Package (PSEP) which was deployed on the Moon by the Apollo 12 astronauts. The Lunar module's ascent stage was jettisoned and sent toward impact on the Moon after Astronauts Charles Conrad Jr. and Alan L. Bean returned to lunar orbit and rejoined Astronaut Richard F. Gordon Jr., in the Command/Service Modules.

  6. Retroactive Generation of Covariance Matrix of Nuclear Model Parameters Using Marginalization Techniques

    SciTech Connect

    Habert, B; De Saint Jean, C; Leal, Luiz C; Rugama, Yolanda

    2010-01-01

    An uncertainty propagation methodology relying on marginalization techniques was recently developed to produce covariance matrices between existing model parameters involved in describing neutron-induced reactions. This work has been implemented in the nuclear data assimilation tool CONRAD. The performance of the code was demonstrated through simplified test cases based on a Reich-Moore description of the {sup 155}Gd(n,{gamma}) reaction. Results are compared with those produced via Monte Carlo techniques.

  7. Astronaut Paul Weitz gets physical examination from Astronaut Joseph Kerwin

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Astronaut Paul J. Weitz, Skylab 2 pilot, gets a physical examination by a fellow crewman during the 28-day Skylab 2 mission. Scientist-Astronaut Joseph P. Kerwin, Skylab 2 science pilot and a doctor of medicine, uses a stethoscope to check the Weitz's heartbeat. They are in the Orbital Workshop crew quarters of the Skylab 1 and 2 space station in Earth orbit. This photograph was taken by Charles Conrad Jr., Skylab 2 commander.

  8. Physicists and Physics in Munich

    NASA Astrophysics Data System (ADS)

    Teichmann, Jürgen; Eckert, Michael; Wolff, Stefan

    We give a tour of Munich and some outlying sites that focuses on the lives and work of the most prominent physicists who lived in the city, Count Rumford, Joseph Fraunhofer, Georg Simon Ohm, Max Planck, Ludwig Boltzmann, Albert Einstein, Wilhelm Conrad Röntgen, Wilhelm Wien, Arnold Sommerfeld, Max von Laue, and Werner Heisenberg. We close with a self-guided tour that describes how to reach these sites in Munich.

  9. The unionid (Bivalvia) fauna of the Sipsey River in northwestern Alabama, an aquatic hotspot

    USGS Publications Warehouse

    McCullagh, W.H.; Williams, J.D.; McGregor, S.W.; Pierson, J.M.; Lydeard, C.

    2002-01-01

    Recent surveys for unionid bivalves were conducted in the mainstem of the Sipsey River and headwater tributaries (Tombigbee River drainage) during the summer and autumn of 1996-1999. A total of 35 species and 22 genera were found. Museum records from the upper Sipsey, based largely on the efforts of H. H. Smith during 1910-11, raised the total number of recorded unionids in the Sipsey to 42. Smith documented 25 species in the river; however, most of his collections were made in the mid- to upper-Sipsey, which has lower diversity. The three most common recently observed species in descending order of abundance were Quadrula asperata (I. Lea, 1861), Pleurobema decisum (I. Lea, 1831), and Tritogonia verrucosa (Rafinesque, 1820). Federally listed species observed recently include Lampsilis perovalis (Conrad, 1834) (threatened), Medionidus acutissimus (I. Lea, 1831) (threatened), P. decisum (endangered), P. perovatum (Conrad, 1834) (endangered), and Potamilus inflatus (I. Lea, 1831) (threatened). Species not observed recently but recorded in prior surveys include Anodontoides radiatus (Conrad, 1834), Arcidens confragosus (Say, 1829), Plectomerus dombeyanus (Valenciennes, 1827), Q. metanevra (Rafinesque, 1820), Q. stapes (I. Lea, 1831) (federally endangered), P. taitianum (I. Lea, 1834) (federally endangered), and Toxolasma parvus (Barnes, 1823). Many, species are known recently or historically by only five or fewer recorded specimens including: A. radiatus, Elliptio arctata (Conrad, 1834), Ligumia recta (Lamarck, 1819), P. taitianum, P. inflatus, Q. aspera (Lea, 1831), Q. metanevra, Q. stapes, T. parvus, Truncilla donaciformis (I. Lea, 1828), Uniomerus tetralasmus (Say, 1831), Utterbackia imbecillis (Say, 1829), A. confragosus, and P. dombeyanus. Unlike the mussel fauna of most Alabama streams, that of the Sipsey River is still relatively intact in terms of species richness despite impacts from mining, silvicultural, and agricultural activities. A concerted effort

  10. Portrait of Gemini 11 prime and backup crews

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Portrait of Gemini 11 prime and backup crews. Seated are the Gemini 11 prime crewmembers (l.-r.) Astronauts Richard F. Gordon Jr., prime crew pilot, and Charles Conrad Jr., prime crew command pilot. Standing are (l.-r.) Astronauts William A. Anders, backup crew pilot, and Neil Armstrong, backup crew command pilot. They are in their space suits next to a mock-up of the Gemini spacecraft.

  11. Skylab 2 astronauts eat space food in wardroom of Skylab trainer

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The three members of the prime crew of the first manned Skylab mission dine on specially prepared Skylab space food in the wardromm of the crew quarters of the Skylab Orbital Workshop (OWS) trainer during Skylab training at the Johnson Space Center. They are, left to right, Scientist-Astronaut Joseph P. Kerwin, science pilot; Astronaut Paul J. Weitz, pilot; and Astronaut Charles Conrad Jr., commander.

  12. Skylab 2 astronauts seen in wardroom of crew quarters of Skylab 1 station

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Two of the three Skylab 2 astronauts are seen in the wardroom of the crew quarters of the Orbital Workshop of the Skylab 1 space station cluster in Earth orbit in this reproduction taken from a color television transmission made by a TV camera aboard the space station. They are preparing to eat a meal. Astronaut Charles Conrad Jr., commander, is in the right foreground. In the background is scientist-astronaut Joseph P. Kerwin, science pilot.

  13. Rock sample brought to earth from the Apollo 12 lunar landing mission

    NASA Technical Reports Server (NTRS)

    1969-01-01

    Close-up view of Apollo 12 sample 12,065 under observation in the Manned Spacecraft Center's Lunar Receiving Laboratory. This sample, collected during the second Apollo 12 extravehicular activity (EVA-2) of Astronauts Charles Conrad Jr., and Alan L. Bean, is a fine-grained rock. Note the glass-lined pits. An idea of the size of the rock can be gained by reference to the gauge on the bottom portion of the number meter.

  14. Inertial confinement fusion reactor cavity analysis: Progress report for the period 1 July 1986 to 30 June 1987

    SciTech Connect

    Peterson, R.R.; MacFarlane, J.J.; Moses, G.A.; El-Afify, M.; Corradini, M.L.

    1987-07-01

    This is a process report for research performed from July 1, 1986 to June 30, 1987, for Lawrence Livermore National Laboratory under subcontract number 9265205 with the project title: Inertial Confinement Fusion Reactor Cavity Analysis. This research generally considers the problems of vaporization and condensation of liquid metal or solid first surface materials in high yield ICF facilities such as reactors or high yield target test experiments. The past year's research consisted of 1.2 man years of effort on three tasks. These tasks were: verify the current vaporization-condensation models in CONRAD through literature surveys of relevant published data, and evaluation and comparison of these data with predictions by CONRAD on condensation phenomena, and with predictions by CONRAD, ZPINCH, and/or MIXERG on radiation phenomena, design a small-scale vaporization experiment by evaluating existing experimental facilities, selecting a primary facility, and conceptually designing an experiment complete with facility parameters and measurables, and design a small-scale condensation experiment including experimental parameters, measurables, and diagnostics. 48 refs.

  15. Granuloside, A Unique Linear Homosesterterpene from the Antarctic Nudibranch Charcotia granulosa.

    PubMed

    Cutignano, Adele; Moles, Juan; Avila, Conxita; Fontana, Angelo

    2015-07-24

    A new homosesterterpene with a unique linear skeleton, named granuloside (1), has been fully characterized from the Antarctic nudibranch Charcotia granulosa Vayssière, 1906 (Mollusca: Gastropoda). The planar structure of 1 was determined by extensive spectroscopic techniques on the methyl derivatives (1a and 1b), and the R absolute configuration at C-4 is suggested by comparison of experimental and calculated ECD spectra of 1b. Granuloside (1) is the first linear homosesterterpene skeleton ever reported and, despite the low molecular complexity, its chemical structure poses many questions about its biogenesis and origin in the nudibranch. PMID:26177282

  16. Identification of genes related to learning and memory in the brain transcriptome of the mollusc, Hermissenda crassicornis.

    PubMed

    Tamvacakis, Arianna N; Senatore, Adriano; Katz, Paul S

    2015-12-01

    The sea slug Hermissenda crassicornis (Mollusca, Gastropoda, Nudibranchia) has been studied extensively in associative learning paradigms. However, lack of genetic information previously hindered molecular-level investigations. Here, the Hermissenda brain transcriptome was sequenced and assembled de novo, producing 165,743 total transcripts. Orthologs of 95 genes implicated in learning were identified. These included genes for a serotonin receptor and a GABA-B receptor subunit that had not been previously described in molluscs, as well as an adenylyl cyclase gene not previously described in gastropods. This study illustrates the Hermissenda transcriptome's potential as an important genetic tool in future learning and memory research.

  17. A surface-associated activity trap for capturing water surface and aquatic invertebrates in wetlands

    USGS Publications Warehouse

    Hanson, M.A.; Roy, C.C.; Euliss, N.H., Jr.; Zimmer, K.D.; Riggs, M.R.; Butler, Malcolm G.

    2000-01-01

    We developed a surface-associated activity trap (SAT) for sampling aquatic invertebrates in wetlands. We compared performance of this trap with that of a conventional activity trap (AT) based on non-detection rates and relative abundance estimates for 13 taxa of common wetland invertebrates and for taxon richness using data from experiments in constructed wetlands. Taxon-specific non-detection rates for ATs generally exceeded those of SATs, and largest improvements using SATs were for Chironomidae and Gastropoda. SATs were efficient at capturing cladocera, Chironomidae, Gastropoda, total Crustacea, and multiple taxa (taxon richness) but were only slightly better than ATs at capturing Dytiscidae. Temporal differences in capture rates were observed only for cladocera, Chironomidae, Dytiscidae, and total Crustacea, with capture efficiencies of SATs usually decreasing from mid-June through mid-July for these taxa. We believe that SATs may be useful for characterizing wetland invertebrate communities and for developing improved measures of prey available to foraging waterfowl and other aquatic birds.

  18. A surface-associated activity trap for capturing water-surface and aquatic invertebrates in wetlands

    USGS Publications Warehouse

    Hanson, M.A.; Roy, C.C.; Euliss, N.H., Jr.; Zimmer, K.D.; Riggs, M.R.; Butler, Malcolm G.

    2000-01-01

    We developed a surface-associated activity trap (SAT) for sampling aquatic invertebrates in wetlands. We compared performance of this trap with that of a conventional activity trap (AT) based on non-detection rates and relative abundance estimates for 13 taxa of common wetland invertebrates and for taxon richness using data from experiments in constructed wetlands. Taxon-specific non-detection rates for ATs generally exceeded those of SATs, and largest improvements using SATs were for Chironomidae and Gastropoda. SATs were efficient at capturing cladocera, Chironomidae, Gastropoda, total Crustacea, and multiple taxa (taxon richness) but were only slightly better than ATs at capturing Dytiscidae. Temporal differences in capture rates were observed only for cladocera, Chironomidae, Dytiscidae, and total Crustacea, with capture efficiencies of SATs usually decreasing from mid-June through mid-July for these taxa. We believe that SATs may be useful for characterizing wetland invertebrate communities and for developing improved measures of prey available to foraging waterfowl and other aquatic birds.

  19. Tolerance values of benthic macroinvertebrates for stream biomonitoring: assessment of assumptions underlying scoring systems worldwide.

    PubMed

    Chang, Feng-Hsun; Lawrence, Justin E; Rios-Touma, Blanca; Resh, Vincent H

    2014-04-01

    Tolerance values (TVs) based on benthic macroinvertebrates are one of the most widely used tools for monitoring the biological impacts of water pollution, particularly in streams and rivers. We compiled TVs of benthic macroinvertebrates from 29 regions around the world to test 11 basic assumptions about pollution tolerance, that: (1) Arthropoda are < tolerant than non-Arthropoda; (2) Insecta < non-Insecta; (3) non-Oligochaeta < Oligochaeta; (4) other macroinvertebrates < Oligochaeta + Chironomidae; (5) other macroinvertebrate taxa < Isopoda + Gastropoda + Hirudinea; (6) Ephemeroptera + Plecoptera + Trichoptera (EPT) < Odonata + Coleoptera + Heteroptera (OCH); (7) EPT < non-EPT insects; (8) Diptera < Insecta; (9) Bivalvia < Gastropoda; (10) Baetidae < other Ephemeroptera; and (11) Hydropsychidae < other Trichoptera. We found that the first eight of these 11 assumptions were supported despite regional variability. In addition, we examined the effect of Best Professional Judgment (BPJ) and non-independence of TVs among countries by performing all analyses using subsets of the original dataset. These subsets included a group based on those systems using TVs that were derived from techniques other than BPJ, and groups based on methods used for TV assignment. The results obtained from these subsets and the entire dataset are similar. We also made seven a priori hypotheses about the regional similarity of TVs based on geography. Only one of these was supported. Development of TVs and the reporting of how they are assigned need to be more rigorous and be better described.

  20. Changes in the bottom fauna of western Lake Erie from 1930 to 1961

    USGS Publications Warehouse

    Carr, John F.; Hiltunen, Jarl K.

    1965-01-01

    Samples were collected at 40 stations in western Lake Erie in 1961 to determine the species composition, distribution, and abundance of macrobenthonic organisms and to document changes since 1930, when a similar survey was made. The fauna in 1961 was composed principally of Oligochaeta, Tendipedidae (7 genera), Sphaeriidae (15 species), and Gastropoda (at least 8 species). Stations with a high density of Oligochaeta were near the principal sources of pollution (Maumee, Raisin, and Detroit rivers). Stations with fewer Oligochaeta and a more diverse fauna were farthest from the river mouths. The population density of the burrowing mayfly, Hexagenia spp., was reduced from an average of 139/m2 in 1930 to less than 1/m2 in 1961. Organisms more abundant near the sources of pollution than in other areas were, in addition to Oligochaeta: the midge, Procladius; the fingernail clam, Sphaerium transversum; and the snail, Valvata sincera (sens. lat.). Organisms sensitive to pollution, such as amphipods, mayfly nymphs, caddisfly larvae, and naiad clams, were scarce and usually at the more lakeward stations. The most important changes in fauna during the 31-year period were: ninefold increase in Oligochaeta; fourfold increase in Tendipedidae; twofold increase in Sphaeriidae; sixfold increase in Gastropoda; and a reduction of Hexagenia to less than 1% of former abundance. The area of pollution (as judged from the abundance of Oligochaeta) increased from 263 km2 in 1930 to 1,020 km2 in 1961.

  1. Dynamic expression of ancient and novel molluscan shell genes during ecological transitions

    PubMed Central

    Jackson, Daniel J; Wörheide, Gert; Degnan, Bernard M

    2007-01-01

    Background The Mollusca constitute one of the most morphologically and ecologically diverse metazoan phyla, occupying a wide range of marine, terrestrial and freshwater habitats. The evolutionary success of the molluscs can in part be attributed to the evolvability of the external shell. Typically, the shell first forms during embryonic and larval development, changing dramatically in shape, colour and mineralogical composition as development and maturation proceeds. Major developmental transitions in shell morphology often correlate with ecological transitions (e.g. from a planktonic to benthic existence at metamorphosis). While the genes involved in molluscan biomineralisation are beginning to be identified, there is little understanding of how these are developmentally regulated, or if the same genes are operational at different stages of the mollusc's life. Results Here we relate the developmental expression of nine genes in the tissue responsible for shell production – the mantle – to ecological transitions that occur during the lifetime of the tropical abalone Haliotis asinina (Vetigastropoda). Four of these genes encode evolutionarily ancient proteins, while four others encode secreted proteins with little or no identity to known proteins. Another gene has been previously described from the mantle of another haliotid vetigastropod. All nine genes display dynamic spatial and temporal expression profiles within the larval shell field and juvenile mantle. Conclusion These expression data reflect the regulatory complexity that underlies molluscan shell construction from larval stages to adulthood, and serves to highlight the different ecological demands placed on each stage. The use of both ancient and novel genes in all stages of shell construction also suggest that a core set of shell-making genes was provided by a shared metazoan ancestor, which has been elaborated upon to produce the range of molluscan shell types we see today. PMID:17845714

  2. 3-D seismic velocity structure of the crust and the uppermost mantle in the northeastern Japan Arc

    NASA Astrophysics Data System (ADS)

    Zhao, Dapeng; Horiuchi, Shigeki; Hasegawa, Akira

    1990-09-01

    3-D seismic velocity structure of the crust and the uppermost mantle beneath the northeastern Japan Arc is investigated by using arrival time data from local earthquakes. We use a velocity model composed of three layers corresponding to the upper crust, the lower crust and the uppermost mantle, respectively. Taking into account the observed regional variation of P n-velocity, the uppermost mantle is further divided into three parts by two P n-velocity boundaries near the coasts of the Japan Sea and the Pacific Ocean. The velocities within the upper crust, the lower crust and the three parts of the uppermost mantle are assumed to be constant. Locations of two P n-velocity boundaries and depth distributions of the Conrad and the Moho discontinuities are expressed by continuous functions of unknown parameters. Station corrections and hypocenters are also introduced to be unknowns. These unknown parameters are determined by inverting arrival time data of P- and S-wave first arrivals and clear later arrivals of P g- and P ∗-waves. The P n-velocity boundary between the land and the Pacific Ocean is located approximately along the Pacific coastline and that between the land and the Japan Sea is nearly along the Japan Sea coastline. The Conrad and the Moho discontinuities are at depths ranging from 14 to 20 km and from 27 to 36 km, respectively. The Conrad and the Moho depths have similar spatial distributions. They are deep beneath the land and become shallower toward the western and the eastern coastlines. Beneath the land, they are shallow in the central part of the Tohoku District and become deeper toward both the north and the south directions. In the north, they become shallow again.

  3. Overland flow generation in two lithologically distinct rainforest catchments

    USGS Publications Warehouse

    Godsey, S.; Elsenbeer, H.; Stallard, R.

    2004-01-01

    Streams on uniformly rainforest-covered, but lithologically very diverse Barro Colorado Island in central Panama?? show remarkable differences in their runoff response to rainfall. This lithological diversity is reflected in equally diverse soilscapes, and our objective was to test the hypothesis that contrasting runoff responses derive from soilscape features that control the generation of overland flow. We determined the soil saturated hydraulic conductivity (Ks) of two neighboring, but hydrologically contrasting catchments (Lutz Creek with a flashy and Conrad Trail with a delayed response to rainfall), and quantified the spatial and temporal frequency of overland flow occurrence. The median Ks values at a depth of 12.5 cm are large enough to rule out Hortonian overland flow, but a marked decrease in K s in Lutz Creek catchment at 30 cm suggests the formation of a perched water table and the generation saturation overland flow; the decrease in Ks in the Conrad Trail catchment is more gradual, and a perched water table is expected to form only at depths below 50 cm. In Lutz Creek, overland flow was generated frequently in time and space and regardless of topographic position, including near the interfluve, with very low thresholds of storm magnitude, duration, intensity and antecedent wetness, whereas in Conrad Trail, overland flow was generated much less frequently and then only locally. We conclude that soilscape features and microtopography are important controls of overland flow generation in these catchments. Our results contribute to the growing evidence that overland flow and forests are not a priori a contradiction in terms. ?? 2004 Elsevier B.V. All rights reserved.

  4. APOLLO 12: A heartstopping launch

    NASA Technical Reports Server (NTRS)

    1974-01-01

    APOLLO 12: A heartstopping launch as the rocket is struck by lightning. From the film documentary 'APOLLO 12: 'Pinpoint for Science'', part of a documentary series on the APOLLO missions made in the early '70's and narrated by Burgess Meredith. APOLLO 12: Second manned lunar landing and return with Charles 'Pete' Conrad, Jr., Richard F. Gordon, and Alan F. Bean. Landed in the Ocean of Storms on November 19, 1969; deployed television camera and ALSEP experiments; two EVA's performed; collected core samples and lunar materials; photographed and retrieved parts from surveyor 3 spacecraft. Mission duration 244hrs 36min 24sec

  5. Nutrition and food concerns of long-term space travel: recommendations for research.

    PubMed

    Sherman, A R; Vodovotz, Y

    1999-01-01

    In order to establish a research agenda for nutrition and food concerns associated with long-duration space travel, a conference was sponsored by the New Jersey-NASA Specialized Center of Research & Training (NJ-NSCORT), NASA, and the University of Houston Conrad N. Hilton College of Hotel & Restaurant Management. Invited papers were presented and are published in this special issue. Following intensive panel discussions and workshops the participants developed recommendations for a research agenda. The recommendations are listed in this introductory article.

  6. VARIFORC: a powerful FORC analysis tool specially suited to environmental magnetic applications

    NASA Astrophysics Data System (ADS)

    Egli, Ramon

    2015-04-01

    VARIFORC is a new tool for the analysis of first-order reversal curves (FORC), especially developed for the highly demanding applications typically occurring in environmental magnetism (e.g. quantitative magnetic component unmixing in weak samples). The currently unique capabilities of VARIFORC are illustrated with examples where the magnetic signature of authigenic minerals (e.g. magnetofossils) is isolated from other magnetic contributions associated with detrital or aeolian inputs in pelagic carbonates. Life demonstrations at the poster stand are possible. VARIFORC is freely available at http://www.conrad-observatory.at/cmsjoomla/de/download.

  7. Chemistry Data for Geothermometry Mapping of Deep Hydrothermal Reservoirs in Southeastern Idaho

    DOE Data Explorer

    Earl Mattson

    2016-01-18

    This dataset includes chemistry of geothermal water samples of the Eastern Snake River Plain and surrounding area. The samples included in this dataset were collected during the springs and summers of 2014 and 2015. All chemical analysis of the samples were conducted in the Analytical Laboratory at the Center of Advanced Energy Studies in Idaho Falls, Idaho. This data set supersedes #425 submission and is the final submission for AOP 3.1.2.1 for INL. Isotopic data collected by Mark Conrad will be submitted in a separate file.

  8. Behavior Analysis in the Era of Medicalization: The State of the Science and Recommendations for Practitioners

    PubMed Central

    2009-01-01

    Recent decades have witnessed an increase in biological explanations of common disorders such as depression and anxiety, a phenonmenon termed “medicalization” (Conrad, 2007). Behavior analysts may find it difficult to implement non-drug treatment with a populace that has become inundated with biological explanations and a preference for medication as the treatment of choice. Research frequently cited in support of medicalization includes studies of drug effectiveness, as well as family studies and studies of brain structure and function. Methodological and interpretation difficulties within those bodies of research are described and recommendations are made so that behavioral practitioners may function optimally within the culture of biological causation. PMID:22477707

  9. NOAA Budget Increases to $4.1 Billion, But Some Key Items Are Reduced

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2008-02-01

    The Bush administration has proposed a US$4.1 billion budget for fiscal year (FY) 2009 for the U.S. National Oceanic and Atmospheric Administration (NOAA). The proposed budget, which would be the agency's largest ever, is $202.6 million, or 5.2%, above the FY 2008 enacted budget. By topping $4 billion and the amount Congress passed for FY 2008, the budget proposal crosses into ``a new threshold,'' according Navy Vice Admiral Conrad Lautenbacher, undersecretary of commerce for oceans and atmosphere and NOAA administrator.

  10. CONRAD—A software framework for cone-beam imaging in radiology

    SciTech Connect

    Maier, Andreas; Choi, Jang-Hwan; Riess, Christian; Keil, Andreas; Fahrig, Rebecca; Hofmann, Hannes G.; Berger, Martin; Fischer, Peter; Schwemmer, Chris; Wu, Haibo; Müller, Kerstin; Hornegger, Joachim

    2013-11-15

    Purpose: In the community of x-ray imaging, there is a multitude of tools and applications that are used in scientific practice. Many of these tools are proprietary and can only be used within a certain lab. Often the same algorithm is implemented multiple times by different groups in order to enable comparison. In an effort to tackle this problem, the authors created CONRAD, a software framework that provides many of the tools that are required to simulate basic processes in x-ray imaging and perform image reconstruction with consideration of nonlinear physical effects.Methods: CONRAD is a Java-based state-of-the-art software platform with extensive documentation. It is based on platform-independent technologies. Special libraries offer access to hardware acceleration such as OpenCL. There is an easy-to-use interface for parallel processing. The software package includes different simulation tools that are able to generate up to 4D projection and volume data and respective vector motion fields. Well known reconstruction algorithms such as FBP, DBP, and ART are included. All algorithms in the package are referenced to a scientific source.Results: A total of 13 different phantoms and 30 processing steps have already been integrated into the platform at the time of writing. The platform comprises 74.000 nonblank lines of code out of which 19% are used for documentation. The software package is available for download at http://conrad.stanford.edu. To demonstrate the use of the package, the authors reconstructed images from two different scanners, a table top system and a clinical C-arm system. Runtimes were evaluated using the RabbitCT platform and demonstrate state-of-the-art runtimes with 2.5 s for the 256 problem size and 12.4 s for the 512 problem size.Conclusions: As a common software framework, CONRAD enables the medical physics community to share algorithms and develop new ideas. In particular this offers new opportunities for scientific collaboration and

  11. Waddington's widget: Hsp90 and the inheritance of acquired characters.

    PubMed

    Ruden, Douglas M; Garfinkel, Mark D; Sollars, Vincent E; Lu, Xiangyi

    2003-10-01

    Conrad Waddington published an influential model for evolution in his 1942 paper, Canalization of Development and Inheritance of Acquired Characters. In this classic, albeit controversial, paper, he proposed that an unknown mechanism exists that conceals phenotypic variation until the organism is stressed. Recent studies have proposed that the highly conserved chaperone Hsp90 could function as a "capacitor," or an "adaptively inducible canalizer," that masks silent phenotypic variation of either genetic or epigenetic origin. This review will discuss evidence for, and arguments against, the role of Hsp90 as a capacitor for morphological evolution, and as a key component of what we call "Waddington's widget."

  12. SKYLAB 2 - SATURN IB MATING

    NASA Technical Reports Server (NTRS)

    1972-01-01

    KENNEDY SPACE CENTER, FL - First and second stages of the Saturn IB launch vehicle for Skylab 2 are visible atop the 129-foot high pedestal installed on a mobile launcher. The pedestal was designed to enable use of mobile launchers for Saturn IB launch vehicles. On the Skylab 2 mission, an Apollo spacecraft will carry Astronauts Charles Conrad, Dr. Joseph Kerwin and Paul Weitz into Earth orbit to rendezvous and dock with Skylab 1, the first US manned orbiting space station. They will enter the space station to live and conduct experiments during a 28-day mission, then return to Earth in the Apollo.

  13. Nutrition and food concerns of long-term space travel: recommendations for research.

    PubMed

    Sherman, A R; Vodovotz, Y

    1999-01-01

    In order to establish a research agenda for nutrition and food concerns associated with long-duration space travel, a conference was sponsored by the New Jersey-NASA Specialized Center of Research & Training (NJ-NSCORT), NASA, and the University of Houston Conrad N. Hilton College of Hotel & Restaurant Management. Invited papers were presented and are published in this special issue. Following intensive panel discussions and workshops the participants developed recommendations for a research agenda. The recommendations are listed in this introductory article. PMID:11541536

  14. Rock sample brought to earth from the Apollo 12 lunar landing mission

    NASA Technical Reports Server (NTRS)

    1969-01-01

    Close-up view of Apollo 12 sample 12,062 under observation in the Manned Spacecraft Center's Lunar Receiving Laboratory. This sample, collected during the second Apollo 12 extravehicular activity (EVA-2) of Astronauts Charles Conrad Jr., and Alan L. Bean, is a medium-grained rock with lath-shaped crystals of feldspar and pyroxene It contains vugs-holes-with crystals growing in them (note right side of exposed portion). An idea of the size of the rock can be gained by reference to the gauge on the bottom portion of the number meter.

  15. [Latin American malacology. Freshwater mollusks from Argentina].

    PubMed

    Rumi, Alejandra; Gregoric, Diego E Gutiérrez; Núñez, Verónica; Darrigran, Gustavo A

    2008-03-01

    A report and an updated list with comments on the species of freshwater molluscs of Argentina which covers an area of 2 777 815 km2 is presented. Distributions of Gastropoda and Bivalvia families, endemic, exotic, invasive as well as entities of sanitary importance are also studied and recommendations on their conservation are provided. Molluscs related to the Del Plata Basin have been thoroughly studied in comparison to others areas of the country. This fauna exhibits relatively the biggest specific richness and keeps its affinity with the fauna of other regions of the basin in areas of Paraguay and Brasil. The 4 500 records of molluscs considered in this paper arise from the study of the collections of Museo Argentino de Ciencias Naturales "Bernardino Rivadavia", Buenos Aires; Museo de La Plata, La Plata and Fundación "Miguel Lillo", Tucumán. These institutions keep very important collections of molluscs in southern South America. Field information has recently been obtained and localities cited by other authors are also included in the data base. Until today, 166 species have been described, 101 belonging to 10 families of Gastropoda and 65 to 7 of Bivalvia. Families with highest specific richness are Lithoglyphidae (22) and Sphaeriidae (25), respectively. The number of endemic species (those present only in Argentina) by family is: Gastropoda: Ampullariidae (1), Cochliopidae (10), Lithoglyphidae (11), Thiariidae (3), Chilinidae (11), Lymnaeidae (2) and Physidae (2?); Bivalvia: Hyriidae (1?); Etheriidae (1?) and Sphaeriidae (10). Families with a distribution that comprise almost the whole country are: the Sphaeriidae and the gastropods Cochliopidae, Chilinidae and Lymnaeidae. Families Erodonidae and Solecurtidae (Bivalvia) were registered in mixohaline environments from Buenos Aires province. Gastropod families Thiaridae and Glacidorbiidae show a very restricted distribution. The rest of the families are present mainly in the center and north of the country

  16. Effects of Silver and Other Metals on the Cytoskeleton

    NASA Technical Reports Server (NTRS)

    Conrad, Gary W.

    1997-01-01

    Directly or indirectly, trace concentrations of silver ion (Ag(+)) stabilize microtubules (Conrad, A.H., et al. Cell Motil. & Cytoskel. 27:117-132), as does taxol (Conrad, A.H., et al. J. Exp. Zool. 262:154-165), an effect with major consequences for cellular shape changes and development. Polymerization of microtubules is gravity-sensitive (Tabony and Job, Proc. Natl. Acad. Sci. USA 89:6948-6952), so trace amounts of Ag(+) may alter cellular ability to respond to gravity. If Ag electrolysis is used to purify water on NASA space vehicles, plants and animals/astronauts will be exposed continuously to Ag(+), a regimen with unknown cellular and developmental consequences. Fertilized eggs of the marine mudsnail, Ilyanassa obsoleta, are the cells in which the effects of A(+) on microtubules were discovered. They distribute visible cytoplasmic contents according to gravity and contain cytoplasmic morphogenetic determinants for heart development. The objectives are to determine if the effects of Ag(+), AU(3+), (of biosensor relevance), or Gd(3+) (inhibitor of some stretch-activated ion channels) on the cytoskeleton (in the presence and absence of mechanical loading) will affect cellular responses to gravity.

  17. Astronaut Richard F. Gordon Aboard Command Module Yankee Clipper

    NASA Technical Reports Server (NTRS)

    1969-01-01

    This is a view of astronaut Richard F. Gordon attaching a high resolution telephoto lens to a camera aboard the Apollo 12 Command Module (CM) Yankee Clipper. The second manned lunar landing mission, Apollo 12 launched from launch pad 39-A at Kennedy Space Center in Florida on November 14, 1969 via a Saturn V launch vehicle. The Saturn V vehicle was developed by the Marshall Space Flight Center (MSFC) under the direction of Dr. Wernher von Braun. Aboard Apollo 12 was a crew of three astronauts: Alan L. Bean, pilot of the Lunar Module (LM), Intrepid; Richard Gordon, pilot of the Command Module (CM), Yankee Clipper; and Spacecraft Commander Charles Conrad. The LM, Intrepid, landed astronauts Conrad and Bean on the lunar surface in what's known as the Ocean of Storms. Their lunar soil activities included the deployment of the Apollo Lunar Surface Experiments Package (ALSEP), finding the unmanned Surveyor 3 that landed on the Moon on April 19, 1967, and collecting 75 pounds (34 kilograms) of rock samples. Astronaut Richard Gordon piloted the CM, Yankee Clipper, in a parking orbit around the Moon. Apollo 12 safely returned to Earth on November 24, 1969.

  18. Bioaccumulation of 210Po in common gastropod and bivalve species from the northern Gulf.

    PubMed

    Uddin, S; Bebhehani, M

    2014-06-01

    This study sets the baseline for the concentration of the natural-series radionuclide polonium-210 in two species of gastropods and four species of bivalves that are common to the Northern Arabian/Persian Gulf. (210)Po is primarily absorbed from water and via ingestion of detrital material by gastropoda and bivalves. This concentrated (210)Po can then be passed along to the next trophic level of the marine food web. The lowest (210)Po concentration was measured in the gastropod Stomatella auricular (10.36-12.39Bq kg(-1)dry) and the highest in the bivalve Marica marmorata (193.51-215.60Bq kg(-1)dry). The measured concentration factor for these molluscs in the northern Gulf varied between 4.8 and 115×10(3), values very similar to the IAEA recommended value for bivalves and gastropods of 2×10(4).

  19. An efficient method for genomic DNA extraction from different molluscs species.

    PubMed

    Pereira, Jorge C; Chaves, Raquel; Bastos, Estela; Leitão, Alexandra; Guedes-Pinto, Henrique

    2011-01-01

    The selection of a DNA extraction method is a critical step when subsequent analysis depends on the DNA quality and quantity. Unlike mammals, for which several capable DNA extraction methods have been developed, for molluscs the availability of optimized genomic DNA extraction protocols is clearly insufficient. Several aspects such as animal physiology, the type (e.g., adductor muscle or gills) or quantity of tissue, can explain the lack of efficiency (quality and yield) in molluscs genomic DNA extraction procedure. In an attempt to overcome these aspects, this work describes an efficient method for molluscs genomic DNA extraction that was tested in several species from different orders: Veneridae, Ostreidae, Anomiidae, Cardiidae (Bivalvia) and Muricidae (Gastropoda), with different weight sample tissues. The isolated DNA was of high molecular weight with high yield and purity, even with reduced quantities of tissue. Moreover, the genomic DNA isolated, demonstrated to be suitable for several downstream molecular techniques, such as PCR sequencing among others.

  20. First record of Planorbis planorbis (Linnaeus) naturally infected with Xiphidiocercariae from Derna, Libya.

    PubMed

    Kamel, E G; Kassem, H H

    1991-04-01

    A review of the literature shows that the fresh water snail Planorbis planorbis (Mollusca: Gastropoda) infected with Xiphidiocercariae has never been recorded in Derna, Libya. In the present paper the first record is made from Wadi Derna (= Darnah), East coast of Libya. The snail harbour Xiphidiocercariae, the percentage of infection during May, 1989, was found to be 7.3%. Morphological description of the snail Planorbis planorbis, Xiphidiocercariae is given in the present investigation. The snail possibly acts as an intermediate host of trematode species in Libya. Further studies are needed to investigate and to observe the exact type of trematode in which the fresh water snail P. planorbis acts as an intermediate host in the life-cycle and to determine the definitive host in Libya.