Modelling the climatic niche of turtles: a deep-time perspective
Schmidt, Daniela N.; Valdes, Paul J.; Holroyd, Patricia A.; Farnsworth, Alexander
2016-01-01
Ectotherms have close physiological ties with the thermal environment; consequently, the impact of future climate change on their biogeographic distributions is of major interest. Here, we use the modern and deep-time fossil record of testudines (turtles, tortoises, and terrapins) to provide the first test of climate on the niche limits of both extant and extinct (Late Cretaceous, Maastrichtian) taxa. Ecological niche models are used to assess niche overlap in model projections for key testudine ecotypes and families. An ordination framework is applied to quantify metrics of niche change (stability, expansion, and unfilling) between the Maastrichtian and present day. Results indicate that niche stability over evolutionary timescales varies between testudine clades. Groups that originated in the Early Cretaceous show climatic niche stability, whereas those diversifying towards the end of the Cretaceous display larger niche expansion towards the modern. Temperature is the dominant driver of modern and past distributions, whereas precipitation is important for freshwater turtle ranges. Our findings demonstrate that testudines were able to occupy warmer climates than present day in the geological record. However, the projected rate and magnitude of future environmental change, in concert with other conservation threats, presents challenges for acclimation or adaptation. PMID:27655766
Martinez, Pablo A; Boeris, Juan M; Sánchez, Julieta; Pastori, María C; Bolzán, Alejandro D; Ledesma, Mario A
2009-12-01
We describe for the first time the karyotypes of two species of Cryptodiran turtles from Argentina, namely, Trachemys dorbigni (Emydidae) and Chelonoidis (Geochelone) donosobarrosi (Testudinidae). The karyotype of T. dorbigni (2n = 50) consists of 13 pairs of macrochromosomes and 12 pairs of microchromosomes, whereas the karyotype of C. donosobarrosi (2n = 52) consists of 11 pairs of macrochromosomes and 15 pairs of microchromosomes. Fluorescence in situ hybridization (FISH) with a (TTAGGG)n telomeric probe showed that the chromosomes of these species have four telomeric signals, two at each end, indicating that none of the chromosomes of T. dorbigni and C. donosobarrosi are telocentric. The fact that no interstitial telomeric signals were observed after FISH, suggests that interstitial telomeric sequences did not have a major role in the chromosomal evolution of these species. Additional data will be needed to elucidate if interstitial telomeric sequences have a major role in the karyotypic evolution of Testudines.
Reynolds, R.P.; Gotte, S.W.; Ernst, C.H.
2007-01-01
The known type specimens of Crocodilia and Testudines in the collection of the Division of Amphibians and Reptiles, National Museum of Natural History, Smithsonian Institution, published through 2006 represent 93 names of taxa. The catalog presents a list of 249 type-specimen records consisting of 39 holotypes, 52 syntypes, 3 lectotypes, 2 neotypes, 132 paratypes, and 21 paralectotypes. The list is arranged alphabetically by family within Crocodilia and Testudines, and alphabetically by genus and species, as described originally within family. Each entry provides both original and current genus and species names, author(s), date of publication, abbreviated type citation, page of original description, and accompanying fi gures and plates (if any), current type status, USNM catalog number, number of specimens, specimen measurement(s), locality, collector, and date collected. Also included for each taxon is the published type locality, type material at other institutions, an etymology, and remarks on corrections or additional data for original type records, changes in type status, and information pertaining to lost, exchanged, or destroyed specimens. An index of scientific names follows the catalog.
Latitudinal diversity gradients in Mesozoic non-marine turtles
NASA Astrophysics Data System (ADS)
Nicholson, David B.; Holroyd, Patricia A.; Valdes, Paul; Barrett, Paul M.
2016-11-01
The latitudinal biodiversity gradient (LBG)-the pattern of increasing taxonomic richness with decreasing latitude-is prevalent in the structure of the modern biota. However, some freshwater taxa show peak richness at mid-latitudes; for example, extant Testudines (turtles, terrapins and tortoises) exhibit their greatest diversity at 25° N, a pattern sometimes attributed to recent bursts of climatically mediated species diversification. Here, we test whether this pattern also characterizes the Mesozoic distribution of turtles, to determine whether it was established during either their initial diversification or as a more modern phenomenon. Using global occurrence data for non-marine testudinate genera, we find that subsampled richness peaks at palaeolatitudes of 15-30° N in the Jurassic, 30-45° N through the Cretaceous to the Campanian, and from 30° to 60° N in the Maastrichtian. The absence of a significant diversity peak in southern latitudes is consistent with results from climatic models and turtle niche modelling that demonstrate a dearth of suitable turtle habitat in Gondwana during the Jurassic and Late Cretaceous. Our analyses confirm that the modern testudinate LBG has a deep-time origin and further demonstrate that LBGs are not always expressed as a smooth, equator-to-pole distribution.
Roberts, Jackson R; Bullard, Stephen A
2017-10-01
Gulf Coast spiny softshell turtles, Apalone spinifera aspera (Agassiz, 1857) (Testudines: Trionychidae) from Canoe Lake (33°47'56.16″N, 86°29'25.02″W; Springville, Alabama) and Round Lake (32°41'50.91″N, 87°14'30.39″W; Perry Lakes State Park, Marion, Alabama), were infected by V. robustum Stunkard, 1928 , Vasotrema longitestis Byrd, 1939 , and Vasotrema rileyae n. sp. The new species differs from its congeners by having papillate suckers, a short testis, an ovary dextral to the oviduct, and a pre-ovarian genital pore that is lateral to the ventral sucker. We studied the newly collected specimens and museum specimens of all congeners to revise the diagnosis of Vasotrema Stunkard, 1926 and redescribe and provide an updated dichotomous key to all species of the genus.
Pereira, Anieli G; Sterli, Juliana; Moreira, Filipe R R; Schrago, Carlos G
2017-08-01
Despite their complex evolutionary history and the rich fossil record, the higher level phylogeny and historical biogeography of living turtles have not been investigated in a comprehensive and statistical framework. To tackle these issues, we assembled a large molecular dataset, maximizing both taxonomic and gene sampling. As different models provide alternative biogeographical scenarios, we have explicitly tested such hypotheses in order to reconstruct a robust biogeographical history of Testudines. We scanned publicly available databases for nucleotide sequences and composed a dataset comprising 13 loci for 294 living species of Testudines, which accounts for all living genera and 85% of their extant species diversity. Phylogenetic relationships and species divergence times were estimated using a thorough evaluation of fossil information as calibration priors. We then carried out the analysis of historical biogeography of Testudines in a fully statistical framework. Our study recovered the first large-scale phylogeny of turtles with well-supported relationships following the topology proposed by phylogenomic works. Our dating result consistently indicated that the origin of the main clades, Pleurodira and Cryptodira, occurred in the early Jurassic. The phylogenetic and historical biogeographical inferences permitted us to clarify how geological events affected the evolutionary dynamics of crown turtles. For instance, our analyses support the hypothesis that the breakup of Pangaea would have driven the divergence between the cryptodiran and pleurodiran lineages. The reticulated pattern in the ancestral distribution of the cryptodiran lineage suggests a complex biogeographic history for the clade, which was supposedly related to the complex paleogeographic history of Laurasia. On the other hand, the biogeographical history of Pleurodira indicated a tight correlation with the paleogeography of the Gondwanan landmasses. Copyright © 2017 Elsevier Inc. All rights reserved.
Alvarez, W Alexander; Gibbons, Paul M; Rivera, Sam; Archer, Linda L; Childress, April L; Wellehan, James F X
2013-03-31
The intranuclear coccidian parasite of Testudines (TINC) is responsible for significant disease in turtles and tortoises causing high mortality and affecting several threatened species. Diagnostic testing has been limited to relatively labor intensive and expensive pan-coccidial PCR and sequencing techniques. A qPCR assay targeting a specific and conserved region of TINC 18S rRNA was designed. The qPCR reaction was run on samples known to be TINC positive and the results were consistent and analytically specific. The assay was able to detect as little as 10 copies of target DNA in a sample. Testing of soil and invertebrates was negative and did not provide any further insights into life cycles. This assay was used to identify TINC in a novel host species, the critically endangered Arakan forest turtle (Heosemys depressa). Copyright © 2012 Elsevier B.V. All rights reserved.
Cavalcante, Manoella Gemaque; Bastos, Carlos Eduardo Matos Carvalho; Nagamachi, Cleusa Yoshiko; Pieczarka, Julio Cesar; Vicari, Marcelo Ricardo; Noronha, Renata Coelho Rodrigues
2018-01-01
Cytogenetic studies show that there is great karyotypic diversity in order Testudines (2n = 26–68), and that this may be mainly attributed to the presence/absence of microchromosomes. Members of the Podocnemididae family have the smallest diploid numbers of this order (2n = 26–28), which may be a derived condition of the group. Diverse studies suggest that repetitive-DNA-rich sites generally act as hotspots for double-strand breaks and chromosomal reorganization. In this context, we used fluorescent in situ hybridization (FISH) to map telomeric sequences (TTAGGG)n, 45S rDNA, and the genes encoding histones H1 and H3 in two species of genus Podocnemis. We also observed conservation of the 45S rDNA and H1 histone sequences (probable case of conserved synteny), but multiple conserved and non-conserved clusters of H3 genes, which colocalized with the interstitial telomeric sequences in the Podocnemis genome. Our results suggest that fusions have occurred between macro and microchromosomes or between microchromosomes, leading to the observed reduction in diploid number in the family Podocnemididae. PMID:29813087
Cavalcante, Manoella Gemaque; Bastos, Carlos Eduardo Matos Carvalho; Nagamachi, Cleusa Yoshiko; Pieczarka, Julio Cesar; Vicari, Marcelo Ricardo; Noronha, Renata Coelho Rodrigues
2018-01-01
Cytogenetic studies show that there is great karyotypic diversity in order Testudines (2n = 26-68), and that this may be mainly attributed to the presence/absence of microchromosomes. Members of the Podocnemididae family have the smallest diploid numbers of this order (2n = 26-28), which may be a derived condition of the group. Diverse studies suggest that repetitive-DNA-rich sites generally act as hotspots for double-strand breaks and chromosomal reorganization. In this context, we used fluorescent in situ hybridization (FISH) to map telomeric sequences (TTAGGG)n, 45S rDNA, and the genes encoding histones H1 and H3 in two species of genus Podocnemis. We also observed conservation of the 45S rDNA and H1 histone sequences (probable case of conserved synteny), but multiple conserved and non-conserved clusters of H3 genes, which colocalized with the interstitial telomeric sequences in the Podocnemis genome. Our results suggest that fusions have occurred between macro and microchromosomes or between microchromosomes, leading to the observed reduction in diploid number in the family Podocnemididae.
Úngari, Letícia Pereira; Santos, André Luiz Quagliatto; O'Dwyer, Lucia Helena; da Silva, Maria Regina Lucas; de Melo Fava, Natália Nasser; Paiva, Guilherme Carrara Moreira; de Melo Costa Pinto, Rogério; Cury, Márcia Cristina
2018-05-01
Based on morphological, morphometric, and molecular data, we describe a new hemoparasite of the genus Haemogregarina Danilewsky 1885, isolated from the Brazilian aquatic turtle Podocnemis unifilis (Testudines: Podocnemididae). The new species, Haemogregarina podocnemis sp. nov. (Apicomplexa: Haemogregarinidae), is characterized by small trophozoites with a single cytoplasmic vacuole on one side; pre-meronts with nuclear chromatin dispersed in the cytoplasm, with or without cytoplasmic vacuoles; meronts that are usually broad and slightly curved (kidney-shaped), with an average of eight small rectangular nuclei; immature gamonts (bean-shaped) with two morphological types: one with nuclear chromatin dispersed in the cytoplasm and the other with nuclei in the middle of the cell; mature gamonts of two morphological types: one with a length equal to or greater than that of the erythrocyte and the width of the nuclei similar to that of the hemoparasite and the other smaller than the erythrocyte with the width of the nuclei less than that of the hemoparasite. This is the first hemogregarine species described that infects the Brazilian turtle Po. unifilis. These findings highlight the need for further studies of Haemogregarina spp. to better determine the biodiversity of this understudied parasite group.
Zeyl, Jeffrey N; Johnston, Carol E
2015-10-01
Animals exhibit unique hearing adaptations in relation to the habitat media in which they reside. This study was a comparative analysis of auditory specialization in relation to habitat medium in Testudines, a taxon that includes both highly aquatic and fully terrestrial members. Evoked potential audiograms were collected in four species groups representing diversity along the aquatic-terrestrial spectrum: terrestrial and fossorial Gopherus polyphemus, terrestrial Terrapene carolina carolina, and aquatic Trachemys scripta and Sternotherus (S. odoratus and S. minor). Additionally, underwater sensitivity was tested in T. c. carolina, T. scripta, and Sternotherus with tympana submerged just below the water surface. In aerial audiograms, T. c. carolina were most sensitive, with thresholds 18 dB lower than Sternotherus. At 100-300 Hz, thresholds in T. c. carolina, G. polyphemus, and T. scripta were similar to each other. At 400-800 Hz, G. polyphemus thresholds were elevated to 11 dB above T. c. carolina. The underwater audiograms of T. c. carolina, T. scripta, and Sternotherus were similar. The results suggest aerial hearing adaptations in emydids and high-frequency hearing loss associated with seismic vibration detection in G. polyphemus. The underwater audiogram of T. c. carolina could reflect retention of ancestral aquatic auditory function.
Werneck, M R; Lima, E H S M; Pires, T; Silva, R J
2015-08-01
The helminth fauna of 31 juvenile specimens of Eretmochelys imbricata from the Brazilian coast was examined. Seventeen individuals were infected with helminths (54.8%). The helminths found were: Diaschistorchis pandus, Cricocephalus albus, Metacetabulum invaginatum, Pronocephalus obliquus (Pronocephalidae), Cymatocarpus solearis (Brachycoeliidae), Styphlotrema solitaria (Styphlotrematidae), Carettacola stunkardi, Amphiorchis caborojoensis (Spirorchiidae), Orchidasma amphiorchis (Telorchiidae), and Anisakis nematode larvae. This report is the first analysis of parasite communities in this host.
Molecular decay of enamel matrix protein genes in turtles and other edentulous amniotes
2013-01-01
Background Secondary edentulism (toothlessness) has evolved on multiple occasions in amniotes including several mammalian lineages (pangolins, anteaters, baleen whales), birds, and turtles. All edentulous amniote clades have evolved from ancestors with enamel-capped teeth. Previous studies have documented the molecular decay of tooth-specific genes in edentulous mammals, all of which lost their teeth in the Cenozoic, and birds, which lost their teeth in the Cretaceous. By contrast with mammals and birds, tooth loss in turtles occurred in the Jurassic (201.6-145.5 Ma), providing an extended time window for tooth gene degradation in this clade. The release of the painted turtle and Chinese softshell turtle genomes provides an opportunity to recover the decayed remains of tooth-specific genes in Testudines. Results We queried available genomes of Testudines (Chrysemys picta [painted turtle], Pelodiscus sinensis [Chinese softshell turtle]), Aves (Anas platyrhynchos [duck], Gallus gallus [chicken], Meleagris gallopavo [turkey], Melopsittacus undulatus [budgerigar], Taeniopygia guttata [zebra finch]), and enamelless mammals (Orycteropus afer [aardvark], Choloepus hoffmanni [Hoffmann’s two-toed sloth], Dasypus novemcinctus [nine-banded armadillo]) for remnants of three enamel matrix protein (EMP) genes with putative enamel-specific functions. Remnants of the AMBN and ENAM genes were recovered in Chrysemys and retain their original synteny. Remnants of AMEL were recovered in both testudines, although there are no shared frameshifts. We also show that there are inactivated copies of AMBN, AMEL and ENAM in representatives of divergent avian lineages including Galloanserae, Passeriformes, and Psittaciformes, and that there are shared frameshift mutations in all three genes that predate the basal split in Neognathae. Among enamelless mammals, all three EMP genes exhibit inactivating mutations in Orycteropus and Choloepus. Conclusions Our results highlight the power of combining fossil and genomic evidence to decipher macroevolutionary transitions and characterize the functional range of different loci involved in tooth development. The fossil record and phylogenetics combine to predict the occurrence of molecular fossils of tooth-specific genes in the genomes of edentulous amniotes, and in every case these molecular fossils have been discovered. The widespread occurrence of EMP pseudogenes in turtles, birds, and edentulous/enamelless mammals also provides compelling evidence that in amniotes, the only unique, non-redundant function of these genes is in enamel formation. PMID:23342979
Genomic V exons from whole genome shotgun data in reptiles.
Olivieri, D N; von Haeften, B; Sánchez-Espinel, C; Faro, J; Gambón-Deza, F
2014-08-01
Reptiles and mammals diverged over 300 million years ago, creating two parallel evolutionary lineages amongst terrestrial vertebrates. In reptiles, two main evolutionary lines emerged: one gave rise to Squamata, while the other gave rise to Testudines, Crocodylia, and Aves. In this study, we determined the genomic variable (V) exons from whole genome shotgun sequencing (WGS) data in reptiles corresponding to the three main immunoglobulin (IG) loci and the four main T cell receptor (TR) loci. We show that Squamata lack the TRG and TRD genes, and snakes lack the IGKV genes. In representative species of Testudines and Crocodylia, the seven major IG and TR loci are maintained. As in mammals, genes of the IG loci can be grouped into well-defined IMGT clans through a multi-species phylogenetic analysis. We show that the reptilian IGHV and IGLV genes are distributed amongst the established mammalian clans, while their IGKV genes are found within a single clan, nearly exclusive from the mammalian sequences. The reptilian and mammalian TRAV genes cluster into six common evolutionary clades (since IMGT clans have not been defined for TR). In contrast, the reptilian TRBV genes cluster into three clades, which have few mammalian members. In this locus, the V exon sequences from mammals appear to have undergone different evolutionary diversification processes that occurred outside these shared reptilian clans. These sequences can be obtained in a freely available public repository (http://vgenerepertoire.org).
Mascarenhas, Carolina S; Müller, Gertrud
2017-08-01
This paper describes a new species of Camallanus found in the freshwater turtle Trachemys dorbigni. Sixty hosts collected in Southern Brazil were examined. All hosts (100%) were parasitized by a new species of Camallanus , which was described as Camallanus emydidius n. sp. The new species differs from other Camallanus species of freshwater turtles mainly because of the morphology of the right spicule, the number of male precloacal and postcloacal papillae, and the presence of "mucrons" in the female posterior extremity.
Deeming, D Charles
2018-05-14
Testudines exhibit considerable variation in the degree of eggshell calcification, which affects eggshell conductance, water physiology of the embryos, and calcium metabolism of embryos. However, the underlying reason for different shell types has not been explored. Phylogenetically controlled analyses examined relationships between egg size, shell mass, and clutch size in ∼200 turtle species from a range of body sizes and assigned by family as laying either rigid- or pliable-shelled eggs. Shell type affected egg breadth relative to pelvic dimensions, egg mass, and relative shell mass but did not affect size, mass, or total shell mass of the clutch. These results suggest that calcium availability may be a function of body size and the type of shell may reflect in part the interplay between clutch size and egg size. It was further concluded that the eggshell probably evolved as a means of physical protection. Differences in shell calcification may not primarily reflect reproductive parameters but rather correlate with the acidity of a species' nesting environment. Low pH environments may have thicker calcareous layer to counteract the erosion caused by the soil and maintain the integrity of the physical barrier. Limited calcium availability may constrain clutch size. More neutral nesting substrates expose eggshells to less erosion so calcification per egg can be reduced and this allows larger clutch sizes. This pattern is also reflected in thick, calcified crocodilian eggs. Further research is needed to test whether eggshell calcification in the testudines correlates with nest pH in order to verify this relationship. © 2018 Wiley Periodicals, Inc.
Hallmann, Konstantin; Griebeler, Eva Maria
2018-06-01
Allometric relationships linking species characteristics to body size or mass (scaling) are important in biology. However, studies on the scaling of life history traits in the reptiles (the nonavian Reptilia) are rather scarce, especially for the clades Crocodilia, Testudines, and Rhynchocephalia (single extant species, the tuatara). Previous studies on the scaling of reptilian life history traits indicated that they differ from those seen in the other amniotes (mammals and birds), but so far most comparative studies used small species samples and also not phylogenetically informed analyses. Here, we analyzed the scaling of nine life history traits with adult body mass for crocodiles ( n = 22), squamates ( n = 294), turtles ( n = 52), and reptiles ( n = 369). We used for the first time a phylogenetically informed approach for crocodiles, turtles, and the whole group of reptiles. We explored differences in scaling relationships between the reptilian clades Crocodilia, Squamata, and Testudines as well as differences between reptiles, mammals, and birds. Finally, we applied our scaling relationships, in order to gain new insights into the degree of the exceptionality of the tuatara's life history within reptiles. We observed for none of the life history traits studied any difference in their scaling with body mass between squamates, crocodiles, and turtles, except for clutch size and egg weight showing small differences between these groups. Compared to birds and mammals, scaling relationships of reptiles were similar for time-related traits, but they differed for reproductive traits. The tuatara's life history is more similar to that of a similar-sized turtle or crocodile than to a squamate.
Shaffer, H Bradley; McCartney-Melstad, Evan; Near, Thomas J; Mount, Genevieve G; Spinks, Phillip Q
2017-10-01
Accurate time-calibrated phylogenies are the centerpiece of many macroevolutionary studies, and the relationship between the size and scale of molecular data sets and the density and accuracy of fossil calibrations is a key element of time tree studies. Here, we develop a target capture array specifically for living turtles, compare its efficiency to an ultraconserved element (UCE) dataset, and present a time-calibrated molecular phylogeny based on 539 nuclear loci sequenced from 26 species representing the breadth of living turtle diversity plus outgroups. Our gene array, based on three fully sequenced turtle genomes, is 2.4 times more variable across turtles than a recently published UCE data set for an identical subset of 13 species, confirming that taxon-specific arrays return more informative data per sequencing effort than UCEs. We used our genomic data to estimate the ages of living turtle clades including a mid-late Triassic origin for crown turtles and a mid-Carboniferous split of turtles from their sister group, Archosauria. By specifically excluding several of the earliest potential crown turtle fossils and limiting the age of fossil calibration points to the unambiguous crown lineage Caribemys oxfordiensis from the Late Jurassic (Oxfordian, 163.5-157.3Ma) we corroborate a relatively ancient age for living turtles. We also provide novel age estimates for five of the ten testudine families containing more than a single species, as well as several intrafamilial clades. Most of the diversity of crown turtles appears to date to the Paleogene, well after the Cretaceous-Paleogene mass extinction 66mya. Copyright © 2017 Elsevier Inc. All rights reserved.
Parris, L.B.; Lamont, M.M.; Carthy, R.R.
2002-01-01
Hatching sea turtles may be at risk to fire ant predation during egg incubation, and especially at risk once pipped from the egg, prior to hatchling emergence from the nest. In addition to direct mortality, fire ants have the potential to inflict debilitating injuries that may directly affect survival of the young. The increased incidence of red imported fire ant induced mortality and envenomization of loggerhead sea turtle hatchlings on Cape San Blas suggests this invasive ant species may pose a serious threat to the future of this genetically distinct population.
A morphological review of the Cuora flavomarginata complex (Testudines: Geoemydidae)
Ernst, C.H.; Laemmerzahl, A.F.; Lovich, J.E.
2008-01-01
A reevaluation of the morphometric and color pattern differences within the Asiatic box turtle, Cuora flavomarginata sensu latu, was conducted in view of determining the taxonomic position of the three currently recognized subspecies: C. f. flavomarginata (Taiwan), C. f. sinensis (southern mainland China), and C. f. evelynae (Ryukyu Islands, Japan). Recent analyses indicate that the allopatric population of C. f. evelynae is the most divergent of the three taxa and shares little possibility for gene exchange with the other two populations. In contrast, the populations of C. f. flavomarginata and C. f. sinensis share many characters. We recommend the recognition of the Ryukyu population as a full species, C. evelynae.
Schärer, Michelle T
2003-06-01
Epibiotic organisms inhabiting non-nesting hawksbill sea turtles, Eretmochelys imbricata (Linnaeus, 1766), are described from Mona and Monito Islands, Puerto Rico. Epibiont samples from 105 turtles of shallow (< 40 m) water foraging habitats were collected and identified to the lowest possible taxon. This epibiotic assemblage consisting of at least 4 algal functional groups and 12 animal phyla represents the greatest phylogenetic diversity for marine turtle epibiota. Six groups are considered new reports for marine turtles. Most epibiont colonization was found on posterior marginal scutes and under overlapping scutes. Ecological attributes of epibiota and their symbiosis with E. imbricata provide a tool to understand basi and epibiont populations.
A primitive protostegid from Australia and early sea turtle evolution
Kear, Benjamin P; Lee, Michael S.Y
2005-01-01
Sea turtles (Chelonioidea) are a prominent group of modern marine reptiles whose early history is poorly understood. Analysis of exceptionally well preserved fossils of Bouliachelys suteri gen. et sp. nov., a large-bodied basal protostegid (primitive chelonioid) from the Early Cretaceous (Albian) of Australia, indicates that early sea turtles were both larger and more diverse than previously thought. The analysis implies at least five distinct sea turtle lineages existed around 100 million years ago. Currently, the postcranially primitive Ctenochelys and Toxochelys are interpreted as crown-group sea turtles closely related to living cheloniids (e.g. Chelonia); in contrast, the new phylogeny suggests that they are transitional (intermediate stem-taxa) between continental testudines and derived, pelagic chelonioids. PMID:17148342
Nematoda of Kinosternon scorpioides (Testudines: Kinosternidae) from Northeastern Brazil.
Viana, Diego C; Rodrigues, João Fabrício M; Madelaire, Carla B; Clara, Ana; Santos, G; Sousa, Alana L
2016-02-01
The scorpion mud turtle (Kinosternon scorpioides) is a small freshwater turtle broadly distributed in South America and commonly consumed in some Brazilian regions. This study aimed to identify the species of helminths that parasitize the digestive tract of K. scorpioides and report infection parameters such as parasite prevalence, mean intensity of the infection, abundance, and the relationship between these nematodes and host body size in this species. We captured 20 adult male K. scorpioides, and 6 animals had nematodes in their gastrointestinal tract. These animals had Serpinema magathi (prevalence = 0.3) and Spiroxys figueiredoi (prevalence = 0.25). There were no correlations between the number of total parasites and carapace length (rs = 0.17, n = 6, P = 0.74) or the length of the gastrointestinal tract (rs = 0.18, n = 6, P = 0.73).
2018-01-01
Trachemys (Testudines: Emydidae) represents one of the most well-known turtle genera today. The evolution of Trachemys, while being heavily documented with fossil representatives, is not well understood. Numerous fossils from the late Hemphillian Gray Fossil Site (GFS) in northeastern Tennessee help to elucidate its evolution. The fossil Trachemys at the GFS represent a new species. The new taxon, Trachemys haugrudi, is described, and currently represents the most thoroughly described fossil emydid species known. A phylogenetic analysis, including 31 species, focusing on the subfamily Deirochelyinae is performed that includes the new fossil species, along with numerous other modern and fossil deirochelyine species, representing the first phylogenetic analysis published that includes several fossil deirochelyines. The phylogenetic analysis, utilizing morphological evidence, provides monophyletic clades of all modern deirochelyines, including Chrysemys, Deirochelys, Pseudemys, Malaclemys, Graptemys, and Trachemys. A strict consensus tree finds the recently described fossil species Graptemys kerneri to be part of a clade of Graptemys + Malaclemys. Three fossil taxa, including one previously referred to Pseudemys (Pseudemys caelata) and two to Deirochelys (Deirochelys carri and Deirochelys floridana) are found to form a clade with modern Deirochelys reticularia reticularia, with D. floridana sister to the other members of the clade. Chrysemys is found to be part of a basal polytomy with Deirochelys in relation to other deirochelyine taxa. Two fossil taxa previously referred to Chrysemys (Chrysemys timida and Chrysemys williamsi) form a paraphyly with the modern Chrysemys picta picta and Deirochelys, and may be referable to distinct genera. Additionally, fossil taxa previously attributed to Trachemys (Trachemys hillii, Trachemys idahoensis, Trachemys inflata, and Trachemys platymarginata) and T. haugrudi are found to form a clade separate from clades of northern and southern Trachemys species, potentially suggesting a distinct lineage of Trachemys with no modern survivors. Hypotheses of phylogenetic relationships mostly agree between the present study and previous ones, although the inclusion of fossil taxa provides further clues to the evolution of parts of the Deirochelyinae. The inclusion of more fossil taxa and characters may help resolve the placement of some taxa, and further elucidate the evolution of these New World turtles. PMID:29456887
Gastrointestinal helminths of the Caspian turtle, Mauremys caspica (Testudines), from Northern Iran.
Youssefi, Mohammad Reza; Mousapour, Ali; Nikzad, Reza; Gonzalez-Solis, David; Halajian, Ali; Rahimi, Mohammad Taghi
2016-03-01
The Caspian turtle (Mauremys caspica) is a semi-aquatic and adaptable reptile. To date, there are no reports on the parasites of this turtle in Iran. Hence, the current survey was designed to prepare a list of the gastrointestinal helminth parasites of the Caspian turtle in North Iran. A total of 34 road-killed individuals (14 males and 20 females) were collected between July 2011 and October 2012 from the Mazandaran province, Iran. All parts of gastrointestinal were parasitologically scrutinized and collected specimens were fixed and preserved in 70 % ethanol. Half of the examined Caspian turtles (17) were infected with at least one parasitic helminth. The list of helminths includes three nematodes: Serpinema microcephalum (Camallanidae), Falcaustra armenica (Kathlaniidae), Oxyuridae sp., and one digenean: Telorchis sp. (Telorchiidae). This is the first report of the gastrointestinal helminth parasites of the Caspian turtle in Iran and all helminth species are reported for the first time in Iran.
Li, Wei; Zhao, Jian; Shi, Yan; Xiao, Feng-Fang; Zhang, Xin-Cheng; Zhu, Xin-Ping
2015-01-01
The complete mitochondrial genome of the Vietnamese three-striped box turtle (Cuora cyclornata) was first determined in this study. It was a circular molecule of 16,594 bp in length, consisting of 37 genes typically found in other vertebrates. The AT content of the overall base composition of the whole mitogenome was 60.39%, while the control region was 70.23%. Two ETAS and 4 CSBs were identified, while a remarkable feature was found in the control region: a large number of (TTATTATA)10 direct tandem repeats followed by (TTATA)n (n=10, 8 and 1), which were spaced into three domains by (TA)n (n=1, 1 and 2). The sequence information could play an important role in the study of phylogenetic relationships in turtles and preservation of genetic resources for helping conservation of the endangered species.
Anquetin, Jérémy; Barrett, Paul M; Jones, Marc E H; Moore-Fay, Scott; Evans, Susan E
2009-03-07
The discovery of a new stem turtle from the Middle Jurassic (Bathonian) deposits of the Isle of Skye, Scotland, sheds new light on the early evolutionary history of Testudinata. Eileanchelys waldmani gen. et sp. nov. is known from cranial and postcranial material of several individuals and represents the most complete Middle Jurassic turtle described to date, bridging the morphological gap between basal turtles from the Late Triassic-Early Jurassic and crown-group turtles that diversify during the Late Jurassic. A phylogenetic analysis places the new taxon within the stem group of Testudines (crown-group turtles) and suggests a sister-group relationship between E. waldmani and Heckerochelys romani from the Middle Jurassic of Russia. Moreover, E. waldmani also demonstrates that stem turtles were ecologically diverse, as it may represent the earliest known aquatic turtle.
de Carvalho, Robson Henrique; Lacerda, Pedro Dutra; da Silva Mendes, Sarah; Barbosa, Bruno Corrêa; Paschoalini, Mariana; Prezoto, Fabio; de Sousa, Bernadete Maria
2015-12-30
Assessment of marine debris ingestion by sea turtles is important, especially to ensure their survival. From January to December 2011, 23 specimens of five species of sea turtles were found dead or dying after being rehabilitated, along the coast of the municipality of Rio de Janeiro, Brazil. To detect the presence of marine debris in the digestive tract of these turtles, we conducted a postmortem examination from the esophagus until the distal portion of the large intestine for each specimen. Of the total number of turtles, 39% had ingested marine debris such as soft plastic, hard plastic, metal, polyethylene terephthalate (PET) bottle caps, human hair, tampons, and latex condoms. Five of the seven sea turtles species are found along the Brazilian coast, where they feed and breed. A large number of animals are exposed to various kinds of threats, including debris ingestion. Copyright © 2015 Elsevier Ltd. All rights reserved.
Identification of a novel herpesvirus in captive Eastern box turtles (Terrapene carolina carolina).
Sim, Richard R; Norton, Terry M; Bronson, Ellen; Allender, Matthew C; Stedman, Nancy; Childress, April L; Wellehan, James F X
2015-02-25
Herpesviruses are significant pathogens of chelonians which most commonly cause upper respiratory tract disease and necrotizing stomatitis. Herpesvirus infection was identified in two populations of captive Eastern box turtles (Terrapene carolina carolina) using histopathology and polymerase chain reaction (PCR) with DNA sequencing. Necrotizing lesions with eosinophilic to amphophilic intranuclear inclusion bodies were identified in the tissues of one hatch-year individual in January 2013, which was herpesvirus positive by PCR. A separate captive group of adults had an observed herpesvirus prevalence of 58% using PCR in July 2011. In these cases, a novel herpesvirus, Terrapene herpesvirus 1 (TerHV1), was identified and serves as the first herpesvirus sequenced in the genus Terrapene. Similar to the other herpesviruses of the Order Testudines, TerHV1 clusters with the genus Scutavirus of the subfamily Alphaherpesvirinae. Copyright © 2014 Elsevier B.V. All rights reserved.
Vaz-Silva, W; Oliveira, R M; Gonzaga, A F N; Pinto, K C; Poli, F C; Bilce, T M; Penhacek, M; Wronski, L; Martins, J X; Junqueira, T G; Cesca, L C C; Guimarães, V Y; Pinheiro, R D
2015-08-01
The region of Volta Grande do Xingu River, in the state of Pará, presents several kinds of land use ranging from extensive cattle farming to agroforestry, and deforestation. Currently, the Belo Monte Hydroelectric Power Plant affects the region. We present a checklist of amphibians and reptiles of the region and discuss information regarding the spatial distribution of the assemblies based on results of Environmental Programmes conducted in the area. We listed 109 amphibian (Anura, Caudata, and Gymnophiona) and 150 reptile (Squamata, Testudines, and Crocodylia) species. The regional species richness is still considered underestimated, considering the taxonomic uncertainty, complexity and cryptic diversity of various species, as observed in other regions of the Amazon biome. Efforts for scientific collection and studies related to integrative taxonomy are needed to elucidate uncertainties and increase levels of knowledge of the local diversity.
Anquetin, Jérémy; Barrett, Paul M.; Jones, Marc E.H.; Moore-Fay, Scott; Evans, Susan E.
2008-01-01
The discovery of a new stem turtle from the Middle Jurassic (Bathonian) deposits of the Isle of Skye, Scotland, sheds new light on the early evolutionary history of Testudinata. Eileanchelys waldmani gen. et sp. nov. is known from cranial and postcranial material of several individuals and represents the most complete Middle Jurassic turtle described to date, bridging the morphological gap between basal turtles from the Late Triassic–Early Jurassic and crown-group turtles that diversify during the Late Jurassic. A phylogenetic analysis places the new taxon within the stem group of Testudines (crown-group turtles) and suggests a sister-group relationship between E. waldmani and Heckerochelys romani from the Middle Jurassic of Russia. Moreover, E. waldmani also demonstrates that stem turtles were ecologically diverse, as it may represent the earliest known aquatic turtle. PMID:19019789
NASA Astrophysics Data System (ADS)
Jannello, Juan Marcos; Cerda, Ignacio A.; de la Fuente, Marcelo S.
2016-04-01
Yaminuechelys is a long-necked chelid turtle whose remains have been recovered from outcrops of the Santonian-Maastrichtian and Danian of South America. With the purpose of providing data about shell sculpturing origin and palaeoecology, the bone histology of several shell elements (including neural, costal, peripheral and plastral plates) of Yaminuechelys is described herein. Histological analysis reveals that Yaminuechelys shares with Chelidae the presence of interwoven structural fibre bundles in the external cortex, and parallel-fibred bone of the internal cortex. The presence of resorption lines in several samples indicates that the particular ornamentation of the external surfaces originated, at least in part, by focalized resorption and new bone deposition. This mechanism for ornamentation origin and maintenance is here described for the first time in a turtle. Compactness of the shell bones is consistent with an aquatic habitat, which supports previous hypothesis based on palaeoenvironmental and morphological data.
Interanal seam loss in Asian turtles of the Cuora flavomarginata complex (Testudines, Geoemydidae)
Ernst, Carl H.; Lovich, Jeffrey E.
2015-01-01
The taxonomy of Asian box turtles of the genus Cuora is complicated by the description of numerous valid and invalid taxa over the last several decades. However, some characteristics used to differentiate species are questionable. Members of the C. flavomarginata complex are defined by some, but not all, taxonomists as having reduced interanal seam lengths relative to other species. We examined the ratio of interanal scute seam length divided by midline anal scute length in C. flavomarginata and C. evelynae. Hatchlings show a seam that divides 100% of the anal scute along the midline. As individuals increase in carapace length, there is a tendency for the percentage to decrease, especially in females, although there is considerable overlap. We suggest that the decrease in interanal seam length is due to abrasion of the plastron on the substrate as turtles grow larger and older. Differences in habitat substrates across the range of the species may contribute to the wide variation we observed.
Ernst, Carl H.; Laemmerzahl, Arndt F.; Lovich, Jeffrey E.
2016-01-01
The turtle Cuora amboinensis has an extensive distribution covering most of southern mainland Asia, Indonesia, and extending to the Philippine Islands. Unlike many species, C. amboinensis occurs on both sides of Wallace's Line separating Asian and Australian flora and fauna. Four subspecies are currently recognized; Cuora a. kamaroma (southern continental Asia, Java and the northern Philippines [introduced]), C. a. lineata (Kachin Province, Myanmar [Burma] and adjacent Yunnan Province, China), C. a. couro (Sumatra, Java, Sumbawa, and adjacent smaller Indonesian islands); and C. a. amboinensis (Moluccas, Sulawesi, Philippines). Five pattern and 33 morphological characters were examined for variation in 691 individuals from throughout the species' range. Our analyses suggest that only two presently recognized subspecies are valid: amboinensis andkamaroma. Neither couro nor lineata are supported by our analysis. We recommend that C. a. couroshould be synonymized with the species C. amboinensis and C. a. lineata with the subspecies C. a. kamaroma.
Cadena, Edwin
2015-01-01
Background. Neochelys franzeni Schleich, 1993 is the only pleurodire or side-necked turtle from the middle Eocene, Messel Pit (the first UNESCO, World Natural Heritage Site in Germany, since 1995). The original description of the species is based on two specimens SMF ME 1091 (Holotype) and 715 (Paratype) housed at the Senckenberg Museum Frankfurt. The excellent preservation of complete and articulated skeletons of this species makes it a key taxon for understanding the evolution and phylogeny of the European Neochelys genus and its relationships with South American and African-Madagascar podocnemidids. Results. Five new specimens of Neochelys franzeni from Messel Pit are described here, together with the redescription of SMF ME 1091 and 715. Specimens correspond to individuals of different ontogenetic stages showing conservative morphology from hatching to adults. A revised diagnosis for the species is presented here, together with its inclusion in a global phylogenetic analysis of Pelomedusoides that shows that this species and the whole Neochelys spp. is sister to the Erymnochelys madagascariensis-Peltocephalus dumerilianus clade within Podocnemididae.
Cadena, Edwin
2016-01-01
Abundant pan-trionychid (soft-shell) turtles specimens have been found in Eocene sequences of central Europe, particularly from two localities in Germany, the Messel Pit (a UNESCO World Natural Heritage Site) and Geiseltal, traditionally attributed to Trionyx messelianus or Rafetoides austriacus . Over the last two decades new specimens of this taxon from these two localities have been discovered and fully prepared. However, they have remained unstudied, as well as their phylogenetic position inside Pan-Trionychidae is unknown. Five new specimens of Palaeoamyda messeliana nov. comb. from Messel Pit and Geiseltal localities are fully described here. A revised diagnosis for the species is also presented here, together with its inclusion in a phylogenetic analysis of Pan-Trionychidae that shows that this species is sister to the extant Amyda cartilaginea , one of the most abundant pan-trionychid (soft-shell) turtles from Asia, both members of the clade Chitrini. The specimens described in here are among the best and most complete fossil pan-trionychid skeletons so far known.
Palacios-Sánchez, Sonia Eugenia; Vega-Cendejas, María Eugenia
2010-12-01
The coexistence of ecologically similar species may occur because of resources distribution, such as prey and habitat type and segregation time, that minimizes the interspecific competition. The changes brought about by Hurricane Isidore in the distribution of food resources by three coexisting fish species of the family Tetraodontidae (Sphoeroides nephelus, S. spengleri and S testudineus), were analyzed at the Carbonera Inlet. Sphoeroides spp. based their food on benthic organisms; principally, they consume mussels (Brachidontes sp.), barnacles (Balanus sp.) and gastropods (Crepidula sp). Before hurricane impact, the three species share the available food resources in different proportions (bivalves, gastropods, barnacles and decapods), according to different strategies that enabled them to coexist and reduce interspecific competition. After the impact, the abundance of available prey decreased and the interespecific competition for food increased, leading to S. testudines and S. nephelus change their trophic spectrum (xiphosurans, amphipods, isopods and detritus) and displacing S. splengleri of the inlet. The distribution of food resources was conditioned by the abundance and diversity of prey, as well as the adaptive response of each species.
de Freitas, Marco Antonio; Vieira, Ruhan Saldanha; Entiauspe-Neto, Omar Machado; Sousa, Samantha Oliveira E; Farias, Tayse; Sousa, Alanna Grazieli; de Moura, Geraldo Jorge Barbosa
2017-01-01
Understanding the biodiversity of an area is the first step for establishing effective interventions for conservation, especially when it comes to herpetofauna, since 4.1% and 9.2%, respectively, of Brazilian amphibians and reptiles are endangered. The aim of this study is to identify the composition of the herpetofauna occurring in the Northwest Amazonian state of Maranhão, with a focus on the Gurupi Biological Reserve and surrounding areas. Samples were collected between May 2012 and October 2013 (18 months), through pitfall traps, time constrained active search, and opportunistic encounters, and these records were supplemented by specimens collected by third parties and by bibliographic records. A total of 131 species were recorded: 31 species of amphibians and 100 species of reptiles (six testudines, 30 lizards, two amphisbaenas, 60 snakes and two alligators), including some species new to the state of Maranhão and the northeast region of Brazil. This inventory contributes to the knowledge of the herpetofauna for the Belém Endemism Center, the most devastated region of the Brazilian Amazon, and considered poorly sampled.
Vandewege, Michael W.; Mangum, Sarah F.; Gabaldón, Toni; Castoe, Todd A.; Ray, David A.; Hoffmann, Federico G.
2016-01-01
Olfactory receptors (ORs) are membrane proteins that mediate the detection of odorants in the environment, and are the largest vertebrate gene family. Comparative studies of mammalian genomes indicate that OR repertoires vary widely, even between closely related lineages, as a consequence of frequent OR gains and losses. Several studies also suggest that mammalian OR repertoires are influenced by life history traits. Sauropsida is a diverse group of vertebrates group that is the sister group to mammals, and includes birds, testudines, squamates, and crocodilians, and represents a natural system to explore predictions derived from mammalian studies. In this study, we analyzed olfactory receptor (OR) repertoire variation among several representative species and found that the number of intact OR genes in sauropsid genomes analyzed ranged over an order of magnitude, from 108 in the green anole to over 1,000 in turtles. Our results suggest that different sauropsid lineages have highly divergent OR repertoire composition that derive from lineage-specific combinations of gene expansions, losses, and retentions of ancestral OR genes. These differences also suggest that varying degrees of adaption related to life history have shaped the unique OR repertoires observed across sauropsid lineages. PMID:26865070
Vervust, Bart; Brecko, Jonathan; Herrel, Anthony
2011-01-01
Studies on the effect of temperature on whole-animal performance traits other than locomotion are rare. Here we investigate the effects of temperature on the performance of the turtle feeding apparatus in a defensive context. We measured bite force and the kinematics of snapping in the Common Snapping Turtle (Chelydra serpentina) over a wide range of body temperatures. Bite force performance was thermally insensitive over the broad range of temperatures typically experienced by these turtles in nature. In contrast, neck extension (velocity, acceleration, and deceleration) and jaw movements (velocity, acceleration, and deceleration) showed clear temperature dependence with peak acceleration and deceleration capacity increasing with increasing temperatures. Our results regarding the temperature dependence of defensive behavior are reflected by the ecology and overall behavior of this species. These data illustrate the necessity for carefully controlling T(b) when carrying out behavioral and functional studies on turtles as temperature affects the velocity, acceleration, and deceleration of jaw and neck extension movements. More generally, these data add to the limited but increasing number of studies showing that temperature may have important effects on feeding and defensive performance in ectotherms. © 2010 Wiley-Liss, Inc.
Patiño-Martinez, Juan; Marco, Adolfo; Quiñones, Liliana; Calabuig, Cecilia P
2010-09-01
Hatchling emergence to the beach surface from deep sand nests occurs without parental care. Social behaviour among siblings is crucial to overcome this first challenge in sea turtles life. This study, carried out at the Caribbean coast of Colombia, describes the emergence social behaviour of hatchlings from eight nests, and assess the nests translocation effects on temporal patterns of emergence. For the first time, we propose that space released by dehydration of shelled albumen globes (SAGs) at the top of the clutch, might be a reproductive advantage, while facilitating neonates to group together in a very limited space, and favouring the synchrony of emergence. The mean time of groups emergence was of 3.3 days, varying between 1 and 6 days. We found that relocation of the nests did not significantly affect the temporal pattern of emergence, which was mainly nocturnal (77.7% of natural nests and 81.7% of translocated ones). The maximum number of emergences to the surface occurred at the lowest air temperatures (22:00h-06:00h). The selective advantage of this pattern is probably related to the greater rate of predation and mortality by hyperthermia observed during the day.
Homeotic shift at the dawn of the turtle evolution
NASA Astrophysics Data System (ADS)
Szczygielski, Tomasz
2017-04-01
All derived turtles are characterized by one of the strongest reductions of the dorsal elements among Amniota, and have only 10 dorsal and eight cervical vertebrae. I demonstrate that the Late Triassic turtles, which represent successive stages of the shell evolution, indicate that the shift of the boundary between the cervical and dorsal sections of the vertebral column occurred over the course of several million years after the formation of complete carapace. The more generalized reptilian formula of at most seven cervicals and at least 11 dorsals is thus plesiomorphic for Testudinata. The morphological modifications associated with an anterior homeotic change of the first dorsal vertebra towards the last cervical vertebra in the Triassic turtles are partially recapitulated by the reduction of the first dorsal vertebra in crown-group Testudines, and they resemble the morphologies observed under laboratory conditions resulting from the experimental changes of Hox gene expression patterns. This homeotic shift hypothesis is supported by the, unique to turtles, restriction of Hox-5 expression domains, somitic precursors of scapula, and brachial plexus branches to the cervical region, by the number of the marginal scute-forming placodes, which was larger in the Triassic than in modern turtles, and by phylogenetic analyses.
Joyce, Walter G; Werneburg, Ingmar; Lyson, Tyler R
2013-01-01
The hooked element in the pes of turtles was historically identified by most palaeontologists and embryologists as a modified fifth metatarsal, and often used as evidence to unite turtles with other reptiles with a hooked element. Some recent embryological studies, however, revealed that this element might represent an enlarged fifth distal tarsal. We herein provide extensive new myological and developmental observations on the hooked element of turtles, and re-evaluate its primary and secondary homology using all available lines of evidence. Digital count and timing of development are uninformative. However, extensive myological, embryological and topological data are consistent with the hypothesis that the hooked element of turtles represents a fusion of the fifth distal tarsal with the fifth metatarsal, but that the fifth distal tarsal dominates the hooked element in pleurodiran turtles, whereas the fifth metatarsal dominates the hooked element of cryptodiran turtles. The term ‘ansulate bone’ is proposed to refer to hooked elements that result from the fusion of these two bones. The available phylogenetic and fossil data are currently insufficient to clarify the secondary homology of hooked elements within Reptilia. PMID:24102560
Rincón, Ascanio D.; Solórzano, Andrés; Langer, Max C.
2015-01-01
The extinct Stereogenyina turtles form a relatively diverse Podocnemididae lineage, with twelve described and phylogenetically positioned species. They are characterized by a wide geographic and temporal range, from the Eocene of Africa to the Pleistocene of Southeast Asia, and a peculiar palate morphology, with a secondary palate that is unique among side-necked turtles. Here, we describe a new Stereogenyina species, based on an almost complete skull from the middle Miocene Capadare Formation, of Venezuela. A new phylogenetic analysis supports the assignment of the new species to the genus Bairdemys. Based on geometric morphometrics analyses, we related the development of the stereogenyin secondary palate with the acquisition of a durophagous diet. Based on a review of the sedimentary environments where their fossils are found, we also propose that stereogenyins were a marine radiation of podocnemidid turtles, as corroborated by previous studies of fossil eggs and limb morphology. These two inferences allowed us to hypothesize that stereogenyins occupied an ecological niche similar to that of the extant Carettini sea turtles, and that the rise of the latter group may be related to the Stereogenyina diversity fall in the end of the Miocene. PMID:26157628
Espinoza, Luis L; Mertins, Omar; Gama, Gabriella S; Fernandes Patta, Ana C M; Mathews, Patrick D
2017-08-01
A new myxosporean species, Myxidium peruviensis n. sp., is described parasitizing the gall bladder of the yellow-spotted river turtle Podocnemis unifilis kept in captivity in an Amazonian Peruvian turtle rescue unit in the city of Iquitos, State of Loreto, Peru. The parasite was found in four of ten (40%) P. unifilis examined. The new species was characterized based on morphological and molecular phylogeny analyses. SSU rDNA sequence of the spores of M. peruviensis n. sp. resulted in 1876 nucleotides and this sequence did no match any of the Myxozoa available in the GenBank. Phylogenetic analysis identified the new species as a sister species of Myxidium turturibus, the unique Myxidium species described in a Neotropical turtle. Nevertheless, the SSU rDNA sequences of the new species and M. turturibus have only a 91.5% similarity. This is the first description and molecular study of a Myxozoa in a reptile from Peru. Considering the status of P. unifilis as vulnerable species, the infection by Myxidium parasites is emphasized as possible disease impeller, representing menace to the turtle conservation. Copyright © 2017 Elsevier B.V. All rights reserved.
Antimicrobial Peptides in Reptiles
van Hoek, Monique L.
2014-01-01
Reptiles are among the oldest known amniotes and are highly diverse in their morphology and ecological niches. These animals have an evolutionarily ancient innate-immune system that is of great interest to scientists trying to identify new and useful antimicrobial peptides. Significant work in the last decade in the fields of biochemistry, proteomics and genomics has begun to reveal the complexity of reptilian antimicrobial peptides. Here, the current knowledge about antimicrobial peptides in reptiles is reviewed, with specific examples in each of the four orders: Testudines (turtles and tortosises), Sphenodontia (tuataras), Squamata (snakes and lizards), and Crocodilia (crocodilans). Examples are presented of the major classes of antimicrobial peptides expressed by reptiles including defensins, cathelicidins, liver-expressed peptides (hepcidin and LEAP-2), lysozyme, crotamine, and others. Some of these peptides have been identified and tested for their antibacterial or antiviral activity; others are only predicted as possible genes from genomic sequencing. Bioinformatic analysis of the reptile genomes is presented, revealing many predicted candidate antimicrobial peptides genes across this diverse class. The study of how these ancient creatures use antimicrobial peptides within their innate immune systems may reveal new understandings of our mammalian innate immune system and may also provide new and powerful antimicrobial peptides as scaffolds for potential therapeutic development. PMID:24918867
Godwin, James; Lovich, Jeffrey E.; Ennen, Joshua R.; Kreiser, Brian R.; Folt, Brian; Lechowicz, Chris
2014-01-01
Map turtles of the genus Graptemys are highly aquatic and rarely undergo terrestrial movements, and limited dispersal among drainages has been hypothesized to drive drainage-specific endemism and high species richness of this group in the southeastern United States. Until recently, two members of the megacephalic “pulchra clade,” Graptemys barbouri andGraptemys ernsti, were presumed to be allopatric with a gap in both species' ranges in the Choctawhatchee River drainage. In this paper, we analyzed variation in morphology (head and shell patterns) and genetics (mitochondrial DNA and microsatellite loci) from G. barbouri, G. ernsti, and Graptemys sp. collected from the Choctawhatchee River drainage, and we document the syntopic occurrence of those species and back-crossed individuals of mixed ancestry in the Choctawhatchee River drainage. Our results provide a first counter-example to the pattern of drainage-specific endemism in megacephalic Graptemys. Geologic events associated with Pliocene and Pleistocene sea level fluctuations and the existence of paleo-river systems appear to have allowed the invasion of the Choctawhatchee system by these species, and the subsequent introgression likely predates any potential human-mediated introduction.
NASA Astrophysics Data System (ADS)
Oliveira, Gustavo R.; Kellner, Alexander W. A.
2017-11-01
Hatchling turtles are rare in the fossil record. Here we report two incomplete juvenile specimens of the genus Araripemys from the Aptian (ca. 115 Ma) Crato Formation (Araripe Basin, Brazil). Although the description of this material does not completely elucidate the ontogeny of this taxon, the analysis of these specimens yield relevant information about diagnostic features of the genus, showing their presence in hatchling such as: skull with nearly oval shape in dorsal view; closely spaced orbits; cervical vertebrae with long vertebral body indicating the presence of a long neck; the extension and the angle of curvature of the axillary (obtuse angle); and unguals arrow-shaped. The small size of the specimens (40-50 mm) and their poor degree of ossification including unfused costal bones indicate that both represent hatchling individuals. The paleoenvironment of the Crato Formation was similar to mangroves, which is corroborated by the presence of juvenile turtles and fishes, anurans and insects. Araripemys barretoi was also recorded in the Romualdo Formation, which represents a lagoon. The fact that this turtle is found in these quite distinct paleoenvironments suggests that this species could be tolerant to distinct salinities levels.
López, Ellie Ann; Hernández-Fernández, Javier; Bernal-Villegas, Jaime
2008-09-01
Over the past few years an important reduction in the number of nesting marine turtle Caretta caretta individuals has been registered in the Colombian Caribbean, raising the question of a possible extinction in the medium-term. A conservation plan is needed. We studied the culture requirements for C. caretta lymphocytes and preliminary karyotype analysis for cytogenetic identification, immunological study and toxicology without the need to kill individuals. Peripheral blood samples were obtained from 47 individuals in Santa Marta, Colombia and tests were made until optimal conditions were established for lymphocyte culture. The karyotype had 56 chromosomes, 32 macrochromosomes and 24 micro-chromosomes. An ideogram showed that C. caretta has four groups of chromosomes. Sexual chromosomes were not observed. These results do not coincide with the karyotype described from the Pacific (Japan). The present study is the first to include a complete description of the chromosome morphology of turtles from the Atlantic Ocean. It is possible that one of the adaptive strategies of this species is genetic interchange with other species of the family, producing viable hybrids. Individuals in this study might be viable hybrids of C. caretta and further molecular studies are needed.
de Freitas, Marco Antonio; Vieira, Ruhan Saldanha; Entiauspe-Neto, Omar Machado; Sousa, Samantha Oliveira e; Farias, Tayse; Sousa, Alanna Grazieli; de Moura, Geraldo Jorge Barbosa
2017-01-01
Abstract Understanding the biodiversity of an area is the first step for establishing effective interventions for conservation, especially when it comes to herpetofauna, since 4.1% and 9.2%, respectively, of Brazilian amphibians and reptiles are endangered. The aim of this study is to identify the composition of the herpetofauna occurring in the Northwest Amazonian state of Maranhão, with a focus on the Gurupi Biological Reserve and surrounding areas. Samples were collected between May 2012 and October 2013 (18 months), through pitfall traps, time constrained active search, and opportunistic encounters, and these records were supplemented by specimens collected by third parties and by bibliographic records. A total of 131 species were recorded: 31 species of amphibians and 100 species of reptiles (six testudines, 30 lizards, two amphisbaenas, 60 snakes and two alligators), including some species new to the state of Maranhão and the northeast region of Brazil. This inventory contributes to the knowledge of the herpetofauna for the Belém Endemism Center, the most devastated region of the Brazilian Amazon, and considered poorly sampled. PMID:28144181
Sex Reversal in Reptiles: Reproductive Oddity or Powerful Driver of Evolutionary Change?
Holleley, Clare E; Sarre, Stephen D; O'Meally, Denis; Georges, Arthur
2016-01-01
Is sex a product of genes, the environment, or both? In this review, we describe the diversity of sex-determining mechanisms in reptiles, with a focus on systems that display gene-environment interactions. We summarise the field and laboratory-based evidence for the occurrence of environmental sex reversal in reptiles and ask whether this is a widespread evolutionary mechanism affecting the evolution of sex chromosomes and speciation in vertebrates. Sex determination systems exist across a continuum of genetic and environmental influences, blurring the lines between what was once considered a strict dichotomy between genetic sex determination and temperature-dependent sex determination. Across this spectrum, we identify the potential for sex reversal in species with clearly differentiated heteromorphic sex chromosomes (Pogona vitticeps, Bassiana duperreyi, Eremias multiocellata, Gekko japonicus), weakly differentiated homomorphic sex chromosomes (Niveoscincus ocellatus), and species with only a weak heritable predisposition for sex (Emys orbicularis, Trachemys scripta). We argue that sex reversal is widespread in reptiles (Testudines, Lacertidae, Agamidae, Scincidae, Gekkonidae) and has the potential to have an impact on individual fitness, resulting in reproductively, morphologically, and behaviourally unique phenotypes. Sex reversal is likely to be a powerful evolutionary force responsible for generating and maintaining lability and diversity in reptile sex-determining modes. © 2016 S. Karger AG, Basel.
Fujiwara, Shin-Ichi
2018-05-01
Deducing the scapular positions of extinct tetrapod skeletons remains difficult, because the scapulae and rib cage are connected with each other not directly by skeletal joint, but by thoracic muscles. In extant non-testudine quadrupedal tetrapods, the top positions of the scapulae/suprascapulae occur at the anterior portion of the rib cage, above the vertebral column and near the median plane. The adequacy of this position was tested using three-dimensional mechanical models of Felis, Rattus and Chamaeleo that assumed stances on a forelimb on a single side and the hindlimbs. The net moment about the acetabulum generated by the gravity force and the contractive forces of the anti-gravity thoracic muscles, and the resistance of the rib to vertical compression between the downward gravity and upward lifting force from the anti-gravity thoracic muscle depend on the scapular position. The scapular position common among quadrupeds corresponds to the place at which the roll and yaw moments of the uplifted portion of the body are negligible, where the pitch moment is large enough to lift the body, and above the ribs having high strength against vertical compression. These relationships between scapular position and rib cage morphology should allow reliable reconstruction of limb postures of extinct taxa. © 2018 Anatomical Society.
Phylogeny, biogeography and diversification patterns of side-necked turtles (Testudines: Pleurodira)
Langer, Max C.; Sterli, Juliana
2018-01-01
Pleurodires or side-necked turtles are today restricted to freshwater environments of South America, Africa–Madagascar and Australia, but in the past they were distributed much more broadly, being found also on Eurasia, India and North America, and marine environments. Two hypotheses were proposed to explain this distribution; in the first, vicariance would have shaped the current geographical distribution and, in the second, extinctions constrained a previously widespread distribution. Here, we aim to reconstruct pleurodiran biogeographic history and diversification patterns based on a new phylogenetic hypothesis recovered from the analysis of the largest morphological dataset yet compiled for the lineage, testing which biogeographical process prevailed during its evolutionary history. The resulting topology generally agrees with previous hypotheses of the group and shows that most diversification shifts were related to the exploration of new niches, e.g. littoral or marine radiations. In addition, as other turtles, pleurodires do not seem to have been much affected by either the Cretaceous–Palaeogene or the Eocene–Oligocene mass extinctions. The biogeographic analyses highlight the predominance of both anagenetic and cladogenetic dispersal events and support the importance of transoceanic dispersals as a more common driver of area changes than previously thought, agreeing with previous studies with other non-turtle lineages. PMID:29657780
Clusella Trullas, Susana; Spotila, James R; Paladino, Frank V
2006-01-01
Studies of metabolism are central to the understanding of the ecology, behavior, and evolution of reptiles. This study focuses on one phase of the sea turtle life cycle, hatchling dispersal, and gives insight into energetic constraints that dispersal imposes on hatchlings. Hatchling dispersal is an energetically expensive phase in the life cycle of the olive ridley turtle Lepidochelys olivacea. Field metabolic rates (FMRs), determined using the doubly labeled water (DLW) method, for L. olivacea hatchlings digging out of their nest chamber, crawling at the sand surface, and swimming were five, four, and seven times, respectively, the resting metabolic rate (RMR). The cost of swimming was 1.5 and 1.8 times the cost of the digging and crawling phases, respectively, and we estimated that if L. olivacea hatchlings swim at frenzy levels, they can rely on yolk reserves to supply energy for only 3-6 d once they reach the ocean. We compared our RMR and FMR values by establishing an interspecific RMR mass-scaling relationship for a wide range of species in the order Testudines and found a scaling exponent of 1.06. This study demonstrates the feasibility of using the DLW method to estimate energetic costs of free-living sea turtle hatchlings and emphasizes the need for metabolic studies in various life-history stages.
Picelli, Amanda Maria; de Carvalho, Aluísio Vasconcelos; Viana, Lúcio André; Malvasio, Adriana
2015-01-01
Seventy-five turtles Podocnemis expansa in the Brazilian Amazon were examined for the presence of ectoparasites and hemoparasites. Samplings were performed in three study areas in the state of Tocantins, Brazil. Twenty-five specimens were sampled per study area (a commercial breeding facility, an indigenous subsistence breeding facility and a wild population of the Javaés River). Hemoparasites of the genus Haemogregarina were found in 66% (50/75) of the turtle specimens, and the infections were restricted to the commercial breeding facility and to the wild population of the Javaés River. The mean level of parasitemia was 54/2,000 erythrocytes (2%). There was no correlation between the body condition index of the chelonians and the level of parasitemia, with no significant difference between genders. No leeches were observed during the physical exams in any of the study areas, but the specimens from the commercial breeding facility were in poor physical condition with shell deformities and the presence of a relatively high amount of skin ulcerations, most likely caused by fungi and bacteria. This was the first study to record the occurrence of hemogregarines on a population scale in P. expansa and helps to increase knowledge about hemoparasites in chelonians in Brazil.
Phylogeny, biogeography and diversification patterns of side-necked turtles (Testudines: Pleurodira)
NASA Astrophysics Data System (ADS)
Ferreira, Gabriel S.; Bronzati, Mario; Langer, Max C.; Sterli, Juliana
2018-03-01
Pleurodires or side-necked turtles are today restricted to freshwater environments of South America, Africa-Madagascar and Australia, but in the past they were distributed much more broadly, being found also on Eurasia, India and North America, and marine environments. Two hypotheses were proposed to explain this distribution; in the first, vicariance would have shaped the current geographical distribution and, in the second, extinctions constrained a previously widespread distribution. Here, we aim to reconstruct pleurodiran biogeographic history and diversification patterns based on a new phylogenetic hypothesis recovered from the analysis of the largest morphological dataset yet compiled for the lineage, testing which biogeographical process prevailed during its evolutionary history. The resulting topology generally agrees with previous hypotheses of the group and shows that most diversification shifts were related to the exploration of new niches, e.g. littoral or marine radiations. In addition, as other turtles, pleurodires do not seem to have been much affected by either the Cretaceous-Palaeogene or the Eocene-Oligocene mass extinctions. The biogeographic analyses highlight the predominance of both anagenetic and cladogenetic dispersal events and support the importance of transoceanic dispersals as a more common driver of area changes than previously thought, agreeing with previous studies with other non-turtle lineages.
Kern, Maximilian M.; Guzy, Jacquelyn C.; Lovich, Jeffrey E.; Gibbons, J. Whitfield; Dorcas, Michael E.
2016-01-01
Because resources are finite, female animals face trade-offs between the size and number of offspring they are able to produce during a single reproductive event. Optimal egg size (OES) theory predicts that any increase in resources allocated to reproduction should increase clutch size with minimal effects on egg size. Variations of OES predict that egg size should be optimized, although not necessarily constant across a population, because optimality is contingent on maternal phenotypes, such as body size and morphology, and recent environmental conditions. We examined the relationships among body size variables (pelvic aperture width, caudal gap height, and plastron length), clutch size, and egg width of diamondback terrapins from separate but proximate populations at Kiawah Island and Edisto Island, South Carolina. We found that terrapins do not meet some of the predictions of OES theory. Both populations exhibited greater variation in egg size among clutches than within, suggesting an absence of optimization except as it may relate to phenotype/habitat matching. We found that egg size appeared to be constrained by more than just pelvic aperture width in Kiawah terrapins but not in the Edisto population. Terrapins at Edisto appeared to exhibit osteokinesis in the caudal region of their shells, which may aid in the oviposition of large eggs.
Biogeographic Dating of Speciation Times Using Paleogeographically Informed Processes
Landis, Michael J.
2017-01-01
Abstract Standard models of molecular evolution cannot estimate absolute speciation times alone, and require external calibrations to do so, such as fossils. Because fossil calibration methods rely on the incomplete fossil record, a great number of nodes in the tree of life cannot be dated precisely. However, many major paleogeographical events are dated, and since biogeographic processes depend on paleogeographical conditions, biogeographic dating may be used as an alternative or complementary method to fossil dating. I demonstrate how a time-stratified biogeographic stochastic process may be used to estimate absolute divergence times by conditioning on dated paleogeographical events. Informed by the current paleogeographical literature, I construct an empirical dispersal graph using 25 areas and 26 epochs for the past 540 Ma of Earth’s history. Simulations indicate biogeographic dating performs well so long as paleogeography imposes constraint on biogeographic character evolution. To gauge whether biogeographic dating may be of practical use, I analyzed the well-studied turtle clade (Testudines) to assess how well biogeographic dating fares when compared to fossil-calibrated dating estimates reported in the literature. Fossil-free biogeographic dating estimated the age of the most recent common ancestor of extant turtles to be from the Late Triassic, which is consistent with fossil-based estimates. Dating precision improves further when including a root node fossil calibration. The described model, paleogeographical dispersal graph, and analysis scripts are available for use with RevBayes. PMID:27155009
Scillitani, Giovanni; Mentino, Donatella; Mastrodonato, Maria
2017-10-01
The secretion of the goblet cells in the intestine of Trachemys scripta elegans was studied in situ by histochemical methods to analyze the diversity of sugar chains, with particular regard to the acidic glycans. Conventional histochemical stains (Periodic acid-Schiff, Alcian Blue pH 2.5, High Iron Diamine) and binding with ten FITC-labelled lectins combined with chemical and enzymatic pre-treatments were used to characterize the oligosaccharidic chains. The intestine can be divided into three regions, i.e. a duodenum, a small intestine and a large intestine. Goblet cells were observed in all the three tracts and presented an acidic secretion. WGA, LFA, PNA and SBA binding was observed only after desulfation. Glycans secreted by the three tracts consist mainly of sulfosialomucins with 1,2-linked fucose, mannosylated, glucosaminylated and subterminal galactosyl/galactosaminylated residuals. Differences among tracts are quantitative rather than qualitative, with sulfated, galactosaminylated and glycosaminylated residuals increasing from duodenum to large intestine, and galactosylated and fucosylated residuals showing an opposite trend. Variation is observed also between apices and bases of villi in both duodenum and small intestine, where sulphation decreases from the base to the apex and glycosylation shows an opposite trend. Functional implication of these findings is discussed in a comparative context. Copyright © 2017 Elsevier Ltd. All rights reserved.
Reptilian exposure to polycyclic aromatic hydrocarbons and associated effects.
Zychowski, Gregory V; Godard-Codding, Céline A J
2017-01-01
Reptiles are an underrepresented taxon in ecotoxicological literature, and the means by which toxicants play a role in population declines are only partially understood. Among the contaminants of interest for reptiles are polycyclic aromatic hydrocarbons (PAHs), a class of organic compounds that is already a concern for numerous other taxa. The objectives of the present review are to summarize the existing literature on reptilian exposure to PAHs and synthesize general conclusions, to identify knowledge gaps within this niche of research, and to suggest future directions for research. Results confirm a relative scarcity of information on reptilian exposure to PAHs, although research continues to grow, particularly after significant contamination events. The orders Testudines and Squamata are better represented than the orders Crocodilia and Rhynchocephalia. For the taxonomic orders with relevant literature (all but Rhynchocephalia), some species are more frequently represented than others. Few studies establish solid cause-effect relationships after reptilian exposure to PAHs, and many more studies are suggestive of effect or increased risk of effect. Despite the scarcity of information in this area, researchers have already employed a wide variety of approaches to address PAH-related questions for reptiles, including molecular techniques, modeling, and field surveys. As more research is completed, a thoughtful interpretation of available and emerging data is necessary to make the most effective use of this information. Environ Toxicol Chem 2017;36:25-35. © 2016 SETAC. © 2016 SETAC.
NASA Astrophysics Data System (ADS)
Vlachos, Evangelos; Cerda, Ignacio; Tsoukala, Evangelia
2015-08-01
Soft-shelled turtles (Pan-Trionychidae) are not included in the present-day chelonian fauna of Greece and have been unknown in the Greek fossil record up to now. Here, we report the first fossil occurrence of a soft-shelled turtle from Greece, originating from the Pliocene Gefira Member (Angelochori Formation), in the lower Axios valley. The corresponding specimens were discovered with several mammalian remains, most of them attributable to the mastodon of Auvergne, Anancus arvernensis. The chelonian material includes five carapacial fragments that belong to the same individual and can be attributed to Pan-Trionychidae based on the typical sculpturing on the dorsal side of the carapace. Most of these bony plates were histologically sampled and thereby provide evidence for the "plywood" structure, another characteristic of pan-trionychids. They represent the first extended sampling of trionychid plates that belong to the same individual, allowing the documentation of the variation of the relevant trionychid morphologies in the carapace. These findings expand the paleobiogeographic range of this taxon to the southern Balkans and Greece and allow a better estimation of the chelonian paleo-fauna of the area. They are also important for the temporal distribution of this clade in the Paleoarctic, as they join specimens from Italy as being the last trionychids in Europe.
Rodrigues, João Fabrício Mota; Diniz-Filho, José Alexandre Felizola
2016-08-01
Habitat may be viewed as an important life history component potentially related to diversification patterns. However, differences in diversification rates between aquatic and terrestrial realms are still poorly explored. Testudines is a group distributed worldwide that lives in aquatic and terrestrial environments, but until now no-one has evaluated the diversification history of the group as a whole. We aim here to investigate the diversification history of turtles and to test if habitat influenced speciation rate in these animals. We reconstructed the phylogeny of the modern species of chelonians and estimated node divergence dates using molecular markers and a Bayesian approach. Then, we used Bayesian Analyses of Macroevolutionary Mixtures to evaluate the diversification history of turtles and evaluate the effect of habitat on this pattern. Our reconstructed phylogeny covered 300 species (87% of the total diversity of the group). We found that the emydid subfamily Deirochelyinae, which forms the turtle hotspot in south-eastern United States, had an increase in its speciation rate, and that Galapagos tortoises had similar increases. Current speciation rates are lower in terrestrial turtles, contradicting studies supporting the idea terrestrial animals diversify more than aquatic species. Our results suggest that habitat, ecological opportunities, island invasions, and climatic factors are important drivers of diversification in modern turtles and reinforce the importance of habitat as a diversification driver. Copyright © 2016 Elsevier Inc. All rights reserved.
Freneau, G E; Sá, V A; Franci, C R; Vieira, D; Freneau, B N
2017-01-01
In order to achieve successful captive breeding the Podocnemis expansa, it is necessary to study their reproductive endocrinology. The purpose of this research was to evaluate and characterize plasma concentrations in gonadotrophic, gonadic, corticosterone and prolactin hormones from Giant Amazon Turtles under captive conditions. Blood samples were collected over a 15 month period. The samples were assayed by the use of radioimmunoassay, prolactin, corticosterone, LH, FSH, testosterone, 17β-estradiol and progesterone. We verified significant seasonal pattern increase in 17β-estradiol levels and decrease in progesterone levels in the course of a year, which indicates vitellogenesis. This is related to normal ovarian cycles and possibly to the functional integrity of the hypothalamus-pituitary-gonad axis of captive females. There were negative correlations between testosterone and corticosterone in the male samples, suggestive of stress (management stress) on the reproductive system. The plasma concentrations of gonadotrophic, gonadic, prolactin and corticosterone hormones may be used as a reference for further research and possible therapeutic approaches. The data collected during this research are unprecedented for this species and may serve as a reference for future research regarding the reproductive cycle of this turtle, also allowing reproductive management while in captivity. Information about these hormones must be gathered from wild populations during different periods of the year for better clarification of the reproductive physiology of this species.
Edwards, Taylor; Karl, Alice E.; Vaughn, Mercy; Rosen, Philip C.; Torres, Cristina Meléndez; Murphy, Robert W.
2016-01-01
Abstract Desert tortoises (Testudines; Testudinidae; Gopherus agassizii group) have an extensive distribution throughout the Mojave, Colorado, and Sonoran desert regions. Not surprisingly, they exhibit a tremendous amount of ecological, behavioral, morphological and genetic variation. Gopherus agassizii was considered a single species for almost 150 years but recently the species was split into the nominate form and Morafka’s desert tortoise, Gopherus morafkai, the latter occurring south and east of the Colorado River. Whereas a large body of literature focuses on tortoises in the United States, a dearth of investigations exists for Mexican animals. Notwithstanding, Mexican populations of desert tortoises in the southern part of the range of Gopherus morafkai are distinct, particularly where the tortoises occur in tropical thornscrub and tropical deciduous forest. Recent studies have shed light on the ecology, morphology and genetics of these southern ‘desert’ tortoises. All evidence warrants recognition of this clade as a distinctive taxon and herein we describe it as Gopherus evgoodei sp. n. The description of the new species significantly reduces and limits the distribution of Gopherus morafkai to desertscrub habitat only. By contrast, Gopherus evgoodei sp. n. occurs in thornscrub and tropical deciduous forests only and this leaves it with the smallest range of the three sister species. We present conservation implications for the newly described Gopherus evgoodei, which already faces impending threats. PMID:27006625
Murphy, Robert W.; Berry, Kristin H.; Edwards, Taylor; Leviton, Alan E.; Lathrop, Amy; Riedle, J. Daren
2011-01-01
Abstract We investigate a cornucopia of problems associated with the identity of the desert tortoise, Gopherus agassizii (Cooper). The date of publication is found to be 1861, rather than 1863. Only one of the three original cotypes exists, and it is designated as the lectotype of the species. Another cotype is found to have been destroyed in the 1906 San Francisco earthquake and subsequent fire. The third is lost. The lectotype is genetically confirmed to be from California, and not Arizona, USA as sometimes reported. Maternally, the holotype of Gopherus lepidocephalus (Ottley & Velázques Solis. 1989) from the Cape Region of Baja California Sur, Mexico is also from the Mojavian population of the desert tortoise, and not from Tiburon Island, Sonora, Mexico as previously proposed. A suite of characters serve to diagnose tortoises west and north of the Colorado River, the Mojavian population, from those east and south of the river in Arizona, USA, and Sonora and Sinaloa, Mexico, the Sonoran population. Species recognition is warranted and because Gopherus lepidocephalus is from the Mojavian population, no names are available for the Sonoran species. Thus, a new species, Gopherus morafkai sp. n., is named and this action reduces the distribution of Gopherus agassizii to only 30% of its former range. This reduction has important implications for the conservation and protection of Gopherus agassizii, which may deserve a higher level of protection. PMID:21976992
Development of the turtle plastron, the order-defining skeletal structure.
Rice, Ritva; Kallonen, Aki; Cebra-Thomas, Judith; Gilbert, Scott F
2016-05-10
The dorsal and ventral aspects of the turtle shell, the carapace and the plastron, are developmentally different entities. The carapace contains axial endochondral skeletal elements and exoskeletal dermal bones. The exoskeletal plastron is found in all extant and extinct species of crown turtles found to date and is synaptomorphic of the order Testudines. However, paleontological reconstructed transition forms lack a fully developed carapace and show a progression of bony elements ancestral to the plastron. To understand the evolutionary development of the plastron, it is essential to know how it has formed. Here we studied the molecular development and patterning of plastron bones in a cryptodire turtle Trachemys scripta We show that plastron development begins at developmental stage 15 when osteochondrogenic mesenchyme forms condensates for each plastron bone at the lateral edges of the ventral mesenchyme. These condensations commit to an osteogenic identity and suppress chondrogenesis. Their development overlaps with that of sternal cartilage development in chicks and mice. Thus, we suggest that in turtles, the sternal morphogenesis is prevented in the ventral mesenchyme by the concomitant induction of osteogenesis and the suppression of chondrogenesis. The osteogenic subroutines later direct the growth and patterning of plastron bones in an autonomous manner. The initiation of plastron bone development coincides with that of carapacial ridge formation, suggesting that the development of dorsal and ventral shells are coordinated from the start and that adopting an osteogenesis-inducing and chondrogenesis-suppressing cell fate in the ventral mesenchyme has permitted turtles to develop their order-specific ventral morphology.
Lacey, Elizabeth A; Collado-Vides, Ligia; Fourqurean, James W
2014-12-01
Green sea turtles, Chelonia mydas, are grazers influencing the distribution of seagrass within shallow coastal ecosystems, yet the drivers behind C. mydas patch use within seagrass beds are largely unknown. Current theories center on food quality (nutrient content) as the plant responds to grazing disturbances; however, no study has monitored these parameters in a natural setting without grazer manipulation. To determine the morphological and physiological responses potentially influencing seagrass recovery from grazing disturbances, seagrasses were monitored for one year under three different grazing scenarios (turtle grazed, fish grazed and ungrazed) in a tropical ecosystem in Akumal Bay, Quintana Roo, Mexico. Significantly less soluble carbohydrates and increased nitrogen and phosphorus content in Thalassia testudinum were indicative of the stresses placed on seagrasses during herbivory. To determine if these physiological responses were the drivers of the heterogeneous grazing behavior by C. mydas recorded in Akumal Bay, patches were mapped and monitored over a six-month interval. The abandoned patches had the lowest standing crop rather than leaf nutrient or rhi- zome soluble carbohydrate content. This suggests a modified Giving Up Density (GUD) behavior: the critical threshold where cost of continued grazing does not provide minimum nutrients, therefore, new patches must be utilized, explains resource abandonment and mechanism behind C. mydas grazing. This study is the first to apply GUD theory, often applied in terrestrial literature, to explain marine herbivore grazing behavior.
The girdles of the oldest fossil turtle, Proterochersis robusta, and the age of the turtle crown
2013-01-01
Background Proterochersis robusta from the Late Triassic (Middle Norian) of Germany is the oldest known fossil turtle (i.e. amniote with a fully formed turtle shell), but little is known about its anatomy. A newly prepared, historic specimen provides novel insights into the morphology of the girdles and vertebral column of this taxon and the opportunity to reassess its phylogenetic position. Results The anatomy of the pectoral girdle of P. robusta is similar to that of other primitive turtles, including the Late Triassic (Carnian) Proganochelys quenstedti, in having a vertically oriented scapula, a large coracoid foramen, a short acromion process, and bony ridges that connect the acromion process with the dorsal process, glenoid, and coracoid, and by being able to rotate along a vertical axis. The pelvic elements are expanded distally and suturally attached to the shell, but in contrast to modern pleurodiran turtles the pelvis is associated with the sacral ribs. Conclusions The primary homology of the character “sutured pelvis” is unproblematic between P. robusta and extant pleurodires. However, integration of all new observations into the most complete phylogenetic analysis that support the pleurodiran nature of P. robusta reveals that this taxon is more parsimoniously placed along the phylogenetic stem of crown Testudines. All current phylogenetic hypotheses therefore support the basal placement of this taxon, imply that the sutured pelvis of this taxon developed independently from that of pleurodires, and conclude that the age of the turtle crown is Middle Jurassic. PMID:24314094
Alves-Júnior, J R F; Lustosa, A P G; Bosso, A C S; Balestra, R A M; Bastos, L F; Miranda, L B; Santos, A L Q
2012-02-01
A count was made of unhatched eggs and hatchling live and dead Podocnemis expansa turtles in 327 natural nests located on the beaches of the Environmental Protection Area (EPA) Meanders of the Araguaia River, to determine the percentage of hatching (94.63%), non-hatching (5.37%), survival (94.24%) and hatchling mortality (5.76%), and the average percentage of dead hatchlings during the 15 days in the nursery (0.97%). The mean number of hatchlings per nest was determined from the sum of the number of live and dead hatchlings divided by the total number of nests, while the mean number of eggs per nest was determined from the sum of live and dead hatchlings and unhatched eggs divided by the number of nests. These calculations yielded the following mean values: live hatchlings (88.98 ± 23.94), dead hatchlings (0.37 ± 0.93), unhatched eggs (5.07 ± 9.57), and total number of eggs (94.42 ± 21.30). The reproductive efficiency of the wild population of P. expansa can be affected by many environmental factors such as temperature, humidity and rainfall. In addition, man-made factors like the presence of chemicals in the water and the potential for infectious disease also have significant impact. The reproductive indices data obtained from this study are indispensable for future investigations of hatching anomalies.
Murphy, R.W.; Berry, K.H.; Edwards, T.; Leviton, A.E.; Lathrop, A.; Riedle, J.D.
2011-01-01
We investigate a cornucopia of problems associated with the identity of the desert tortoise, Gopherus agassizii (Cooper). The date of publication is found to be 1861, rather than 1863. Only one of the three original cotypes exists, and it is designated as the lectotype of the species. Another cotype is found to have been destroyed in the 1906 San Francisco earthquake and subsequent fire. The third is lost. The lectotype is genetically confirmed to be from California, and not Arizona, USA as sometimes reported. Maternally, the holotype of G. lepidocephalus (Ottley & Vel??zques Solis. 1989) from the Cape Region of Baja California Sur, Mexico is also from the Mojavian population of the desert tortoise, and not from Tiburon Island, Sonora, Mexico as previously proposed. A suite of characters serve to diagnose tortoises west and north of the Colorado River, the Mojavian population, from those east and south of the river in Arizona, USA, and Sonora and Sinaloa, Mexico, the Sonoran population. Species recognition is warranted and because G. lepidocephalus is from the Mojavian population, no names are available for the Sonoran species. Thus, a new species, Gopherus morafkai sp. n., is named and this action reduces the distribution of G. agassizii to only 30% of its former range. This reduction has important implications for the conservation and protection of G. agassizii, which may deserve a higher level of protection. ?? Robert W. Murphy et al.
Murphy, Robert K.; Berry, Kristin; Edwards, Taylor; Leviton, Alan E.; Lathrop, Amy; Riedle, J. Daren
2011-01-01
We investigate a cornucopia of problems associated with the identity of the desert tortoise, Gopherus agassizii Cooper. The date of publication is found to be 1861, rather than 1863. Only one of the three original cotypes exists, and it is designated as the lectotype of the species. Another cotype is found to have been destroyed in the 1906 San Francisco earthquake and subsequent fire. The third is lost. The lectotype is genetically confirmed to be from California, and not Arizona, USA as sometimes reported. Maternally, the holotype of G. lepidocephalus Ottley et Velázques Solis, 1989 from the Cape Region of Baja California Sur, Mexico is also from the Mojavian population of the desert tortoise, and not from Tiburon Island, Sonora, Mexico as previously proposed. A suite of characters serve to diagnose tortoises west and north of the Colorado River, the Mojavian population, from those east and south of the river in Arizona, USA and Sonora and Sinaloa, Mexico, the Sonoran population. Species recognition is warranted and because G. lepidocephalus is from the Mojavian population no names are available for the Sonoran species. Thus, a new species, Gopherus morafkai sp. n., is named and this action reduces the distribution of G. agassizii to only 30% of its former range. This reduction has important implications for the conservation and protection of G. agassizii, which may deserve a higher level of protection.
Distribution of RPTLN Genes Across Reptilia: Hypothesized Role for RPTLN in the Evolution of SVMPs.
Sanz-Soler, Raquel; Sanz, Libia; Calvete, Juan J
2016-11-01
We report the cloning, full-length sequencing, and broad distribution of reptile-specific RPTLN genes across a number of Anapsida (Testudines), Diapsida (Serpentes, Sauria), and Archosauria (Crocodylia) taxa. The remarkable structural conservation of RPTLN genes in species that had a common ancestor more than 250 million years ago, their low transcriptional level, and the lack of evidence for RPTLN translation in any reptile organ investigated, suggest for this ancient gene family a yet elusive function as long noncoding RNAs. The high conservation in extant snake venom metalloproteinases (SVMPs) of the signal peptide sequence coded for by RPTLN genes strongly suggests that this region may have played a key role in the recruitment and restricted expression of SVMP genes in the venom gland of Caenophidian snakes, some 60-50 Mya. More recently, 23-16 Mya, the neofunctionalization of an RPTLN copy in the venom gland of snakes of the genera Macrovipera and Daboia marked the beginning of the evolutionary history of a new family of disintegrins, the α 1 β 1 -collagen binding antagonists, short-RTS/KTS disintegrins. This evolutionary scenario predicts that venom gland RPTLN and SVMP genes may share tissue-specific regulatory elements. Future genomic studies should support or refute this hypothesis. © The Author 2016. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.
Archelosaurian Color Vision, Parietal Eye Loss, and the Crocodylian Nocturnal Bottleneck.
Emerling, Christopher A
2017-03-01
Vertebrate color vision has evolved partly through the modification of five ancestral visual opsin proteins via gene duplication, loss, and shifts in spectral sensitivity. While many vertebrates, particularly mammals, birds, and fishes, have had their visual opsin repertoires studied in great detail, testudines (turtles) and crocodylians have largely been neglected. Here I examine the genomic basis for color vision in four species of turtles and four species of crocodylians, and demonstrate that while turtles appear to vary in their number of visual opsins, crocodylians experienced a reduction in their color discrimination capacity after their divergence from Aves. Based on the opsin sequences present in their genomes and previous measurements of crocodylian cones, I provide evidence that crocodylians have co-opted the rod opsin (RH1) for cone function. This suggests that some crocodylians might have reinvented trichromatic color vision in a novel way, analogous to several primate lineages. The loss of visual opsins in crocodylians paralleled the loss of various anatomical features associated with photoreception, attributed to a "nocturnal bottleneck" similar to that hypothesized for Mesozoic mammals. I further queried crocodylian genomes for nonvisual opsins and genes associated with protection from ultraviolet light, and found evidence for gene inactivation or loss for several of these genes. Two genes, encoding parietopsin and parapinopsin, were additionally inactivated in birds and turtles, likely co-occurring with the loss of the parietal eye in these lineages. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
The head and neck anatomy of sea turtles (Cryptodira: Chelonioidea) and skull shape in Testudines.
Jones, Marc E H; Werneburg, Ingmar; Curtis, Neil; Penrose, Rod; O'Higgins, Paul; Fagan, Michael J; Evans, Susan E
2012-01-01
Sea turtles (Chelonoidea) are a charismatic group of marine reptiles that occupy a range of important ecological roles. However, the diversity and evolution of their feeding anatomy remain incompletely known. Using computed tomography and classical comparative anatomy we describe the cranial anatomy in two sea turtles, the loggerhead (Caretta caretta) and Kemp's ridley (Lepidochelys kempii), for a better understanding of sea turtle functional anatomy and morphological variation. In both taxa the temporal region of the skull is enclosed by bone and the jaw joint structure and muscle arrangement indicate that palinal jaw movement is possible. The tongue is relatively small, and the hyoid apparatus is not as conspicuous as in some freshwater aquatic turtles. We find several similarities between the muscles of C. caretta and L. kempii, but comparison with other turtles suggests only one of these characters may be derived: connection of the m. adductor mandibulae internus into the Pars intramandibularis via the Zwischensehne. The large fleshy origin of the m. adductor mandibulae externus Pars superficialis from the jugal seems to be a characteristic feature of sea turtles. In C. caretta and L. kempii the ability to suction feed does not seem to be as well developed as that found in some freshwater aquatic turtles. Instead both have skulls suited to forceful biting. This is consistent with the observation that both taxa tend to feed on relatively slow moving but sometimes armoured prey. The broad fleshy origin of the m. adductor mandibulae externus Pars superficialis may be linked to thecheek region being almost fully enclosed in bone but the relationship is complex.
Camarata, Troy; Howard, Alexis; Elsey, Ruth M; Raza, Sarah; O'Connor, Alice; Beatty, Brian; Conrad, Jack; Solounias, Nikos; Chow, Priscilla; Mukta, Saima; Vasilyev, Aleksandr
2016-01-01
New nephron formation (nephrogenesis) ceases in mammals around birth and is completely absent in adults. In contrast, postembryonic nephrogenesis is well documented in the mesonephric kidneys of fishes and amphibians. The transient mesonephros in reptiles (including birds) and mammals is replaced by the metanephros during embryogenesis. Thus, one may speculate that postembryonic nephrogenesis is restricted to the mesonephric kidney. Previous reports have suggested the metanephros of non-avian reptiles (hereafter reptiles) may continually form nephrons throughout life. We investigated the presence of adult nephrogenesis in reptiles by examining adult kidneys from several species including Trachemys scripta, Chrysemys picta, Boa constrictor, Tupinambis tegu, Anolis carolinensis, and Alligator mississipiensis among others. We found that all major reptilian groups (Testudines, Crocodylia, and Squamates) showed the presence of adult nephrogenesis. The total amount of nephrogenesis varied greatly between species with turtles displaying the highest density of nephrogenesis. In contrast, we were unable to detect adult nephrogenesis in monotremes, and in the iguanid A. carolinensis. Nephron progenitor cells express the transcription factor Six2, which in mammals, becomes downregulated as the progenitor cell population is exhausted and nephrogenesis ends. Using the alligator as a model, we were able to detect Six2-positive cap mesenchyme cells in the adult kidney, which spatially correlated with areas of nephrogenesis. These results suggest that the metanephric kidney of reptiles has maintained the ability to continually grow new nephrons during postembryonic life, a process lost early in mammalian evolution, likely due to the persistence of a Six2-expressing progenitor cell population.
Biogeographic Dating of Speciation Times Using Paleogeographically Informed Processes.
Landis, Michael J
2017-03-01
Standard models of molecular evolution cannot estimate absolute speciation times alone, and require external calibrations to do so, such as fossils. Because fossil calibration methods rely on the incomplete fossil record, a great number of nodes in the tree of life cannot be dated precisely. However, many major paleogeographical events are dated, and since biogeographic processes depend on paleogeographical conditions, biogeographic dating may be used as an alternative or complementary method to fossil dating. I demonstrate how a time-stratified biogeographic stochastic process may be used to estimate absolute divergence times by conditioning on dated paleogeographical events. Informed by the current paleogeographical literature, I construct an empirical dispersal graph using 25 areas and 26 epochs for the past 540 Ma of Earth's history. Simulations indicate biogeographic dating performs well so long as paleogeography imposes constraint on biogeographic character evolution. To gauge whether biogeographic dating may be of practical use, I analyzed the well-studied turtle clade (Testudines) to assess how well biogeographic dating fares when compared to fossil-calibrated dating estimates reported in the literature. Fossil-free biogeographic dating estimated the age of the most recent common ancestor of extant turtles to be from the Late Triassic, which is consistent with fossil-based estimates. Dating precision improves further when including a root node fossil calibration. The described model, paleogeographical dispersal graph, and analysis scripts are available for use with RevBayes. © The Author(s) 2016. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Comparing and combining distance-based and character-based approaches for barcoding turtles.
Reid, B N; LE, M; McCord, W P; Iverson, J B; Georges, A; Bergmann, T; Amato, G; Desalle, R; Naro-Maciel, E
2011-11-01
Molecular barcoding can serve as a powerful tool in wildlife forensics and may prove to be a vital aid in conserving organisms that are threatened by illegal wildlife trade, such as turtles (Order Testudines). We produced cytochrome oxidase subunit one (COI) sequences (650 bp) for 174 turtle species and combined these with publicly available sequences for 50 species to produce a data set representative of the breadth of the order. Variability within the barcode region was assessed, and the utility of both distance-based and character-based methods for species identification was evaluated. For species in which genetic material from more than one individual was available (n = 69), intraspecific divergences were 1.3% on average, although divergences greater than the customary 2% barcode threshold occurred within 15 species. High intraspecific divergences could indicate species with a high degree of internal genetic structure or possibly even cryptic species, although introgression is also probable in some of these taxa. Divergences between species of the same genus were 6.4% on average; however, 49 species were <2% divergent from congeners. Low levels of interspecific divergence could be caused by recent evolutionary radiations coupled with the low rates of mtDNA evolution previously observed in turtles. Complementing distance-based barcoding with character-based methods for identifying diagnostic sets of nucleotides provided better resolution in several cases where distance-based methods failed to distinguish species. An online identification engine was created to provide character-based identifications. This study constitutes the first comprehensive barcoding effort for this seriously threatened order. © 2011 Blackwell Publishing Ltd.
Volonterio, Odile
2010-12-01
Temnocephala brevicornis Monticelli, 1889 is the only species of the genus Temnocephala Blanchard, 1849 reported from chelonians to date. During a survey of the species of Temnocephala extant in southern Uruguay, two new species were found on the chelonian Hydromedusa tectifera Cope, 1869. They are described here as Temnocephala pereirai n. sp. and Temnocephala cuocoloi n. sp. Both resemble T. brevicornis, but differ in the morphometry of the penial stylet, and in qualitative details of the reproductive complex. Temnocephala pereirai n. sp. differs from T. brevicornis by having a massive, cylindrical sphincter in the distal portion of the vagina, and a seminal vesicle that opens into the subpolar to equatorial portion of the contractile vesicle. In addition, the penial stylet in Temnocephala pereirai n. sp. is large in relation to body size, straight and more slender, having the distal portion of its shaft slightly sinuous, and a smaller introvert equipped with about 16 distal crowns of smaller spines. Temnocephala cuocoloi n. sp. is most similar to T. brevicornis, but differs by having a smaller, curved penial stylet that has a smaller introvert in relation to stylet size, with about 10 distal crowns of smaller spines. A key to the species of the Temnocephala from chelonians is provided. This study supports the validity of the following characters previously proposed for the taxonomy of the genus Temnocephala: the shape of the sphincters in the female reproductive system, the shape of the penial stylet, and the number, size, and position of spines in the introvert.
Development of the turtle plastron, the order-defining skeletal structure
Rice, Ritva; Kallonen, Aki; Cebra-Thomas, Judith; Gilbert, Scott F.
2016-01-01
The dorsal and ventral aspects of the turtle shell, the carapace and the plastron, are developmentally different entities. The carapace contains axial endochondral skeletal elements and exoskeletal dermal bones. The exoskeletal plastron is found in all extant and extinct species of crown turtles found to date and is synaptomorphic of the order Testudines. However, paleontological reconstructed transition forms lack a fully developed carapace and show a progression of bony elements ancestral to the plastron. To understand the evolutionary development of the plastron, it is essential to know how it has formed. Here we studied the molecular development and patterning of plastron bones in a cryptodire turtle Trachemys scripta. We show that plastron development begins at developmental stage 15 when osteochondrogenic mesenchyme forms condensates for each plastron bone at the lateral edges of the ventral mesenchyme. These condensations commit to an osteogenic identity and suppress chondrogenesis. Their development overlaps with that of sternal cartilage development in chicks and mice. Thus, we suggest that in turtles, the sternal morphogenesis is prevented in the ventral mesenchyme by the concomitant induction of osteogenesis and the suppression of chondrogenesis. The osteogenic subroutines later direct the growth and patterning of plastron bones in an autonomous manner. The initiation of plastron bone development coincides with that of carapacial ridge formation, suggesting that the development of dorsal and ventral shells are coordinated from the start and that adopting an osteogenesis-inducing and chondrogenesis-suppressing cell fate in the ventral mesenchyme has permitted turtles to develop their order-specific ventral morphology. PMID:27114549
Molina, Francisco J; Leynaud, Gerardo C
2017-10-01
Ectotherm species are not capable of generating metabolic heat; therefore, they present different strategies for regulating their body temperatures, ranging from a precise degree of thermoregulation to a passive thermoconformity with ambient temperatures. In reptiles, aerial basking is the most common mechanism for gaining heat. However, among aquatic reptiles, such as freshwater turtles, aquatic basking is also frequent. Hydromedusa tectifera is a turtle of exclusively aquatic and nocturnal habits widely distributed in South America. We studied the relationship between body temperature (Tb) of H. tectifera and its habitat, and explored the effects of sex, life stage and body size and mass on Tb. Fieldwork was conducted in two streams of a mountain area of central Argentina. We recorded cloacal temperature, size and mass of 84 turtles. We also determined individuals' sex and life stage (adult/juvenile). Regarding ambient temperatures, we measured water temperature on the surface (Tsurf) and at depth of turtle capture (Tdepth) and air temperature. Mean Tb was 18.58°C (Min = 10.20°C; Max = 25.70°C). Tsurf and Tdepth were highly correlated. Multi-model analysis using Akaike criterion indicated that Tb was strongly associated with water temperature, whereas air temperature and body size and mass did not show a significant effect. There was also no effect of turtle sex or life stage on Tb. Our results indicate that H. tectifera is a thermoconformer and eurythermal species. A nocturnal pattern of activity and a fully aquatic lifestyle are suggested as determinant factors. Copyright © 2017 Elsevier Ltd. All rights reserved.
Ennen, J.R.; Kreiser, B.R.; Qualls, C.P.; Lovich, J.E.
2010-01-01
The turtle genus Graptemys consists of 15 recognized taxa, distinguished largely on the basis of pigmentation pattern (i.e., soft tissue and shell), head size, and shell morphology. However, phylogenetic studies have shown limited sequence divergence within the genus and between Graptemys oculifera and Graptemys flavimaculata relative to most other members of the Emydidae. Graptemys oculifera of the Pearl River drainage and G. flavimaculata of the Pascagoula River drainage have been recognized as species since 1890 and 1954, respectively. However, the description of G. flavimaculata was based on a limited number of morphological characters. Several of these characters overlap between G. flavimaculata and G. oculifera, and no attempt was made to test for significant morphological differentiation. In this study, we reevaluated the morphological and genetic distinctiveness of G. flavimaculata and G. oculifera with (1) multivariate statistical analyses of 44 morphological characters and (2) 1,560 bp of sequence data from two mitochondrial genes (control region and ND4). The morphological and molecular analyses produced incongruent results. The principal components analysis ordinations separated the two species along a pigmentation gradient with G. flavimaculata having more yellow pigmentation than G. oculifera. Likewise, clustering analyses separated the specimens into two distinct groups with little overlap between the species. Our mitochondrial data supported previous findings of limited genetic differentiation between the two species. However, the results of our morphological analyses, in conjunction with recently published nuclear gene sequence data, support the continued recognition of the two species. Copyright 2010 Society for the Study of Amphibians and Reptiles.
Camarata, Troy; Howard, Alexis; Elsey, Ruth M.; Raza, Sarah; O’Connor, Alice; Beatty, Brian; Conrad, Jack; Solounias, Nikos; Chow, Priscilla; Mukta, Saima; Vasilyev, Aleksandr
2016-01-01
New nephron formation (nephrogenesis) ceases in mammals around birth and is completely absent in adults. In contrast, postembryonic nephrogenesis is well documented in the mesonephric kidneys of fishes and amphibians. The transient mesonephros in reptiles (including birds) and mammals is replaced by the metanephros during embryogenesis. Thus, one may speculate that postembryonic nephrogenesis is restricted to the mesonephric kidney. Previous reports have suggested the metanephros of non-avian reptiles (hereafter reptiles) may continually form nephrons throughout life. We investigated the presence of adult nephrogenesis in reptiles by examining adult kidneys from several species including Trachemys scripta, Chrysemys picta, Boa constrictor, Tupinambis tegu, Anolis carolinensis, and Alligator mississipiensis among others. We found that all major reptilian groups (Testudines, Crocodylia, and Squamates) showed the presence of adult nephrogenesis. The total amount of nephrogenesis varied greatly between species with turtles displaying the highest density of nephrogenesis. In contrast, we were unable to detect adult nephrogenesis in monotremes, and in the iguanid A. carolinensis. Nephron progenitor cells express the transcription factor Six2, which in mammals, becomes downregulated as the progenitor cell population is exhausted and nephrogenesis ends. Using the alligator as a model, we were able to detect Six2-positive cap mesenchyme cells in the adult kidney, which spatially correlated with areas of nephrogenesis. These results suggest that the metanephric kidney of reptiles has maintained the ability to continually grow new nephrons during postembryonic life, a process lost early in mammalian evolution, likely due to the persistence of a Six2-expressing progenitor cell population. PMID:27144443
Hutchison, J. Howard; Townsend, K. E. Beth; Adrian, Brent; Jager, Daniel
2017-01-01
We described newly discovered baenid specimens from the Uintan North American Land Mammal Age (NALMA), in the Uinta Formation, Uinta Basin, Utah. These specimens include a partial skull and several previously undescribed postcranial elements of Baena arenosa, and numerous well-preserved shells of B. arenosa and Chisternon undatum. Baenids from the Uintan NALMA (46.5–40 Ma) are critical in that they provide valuable insight into the morphology and evolution of the diverse and speciose baenid family near the end of its extensive radiation, just prior to the disappearance of this clade from the fossil record. These Uintan specimens greatly increase the known variation in these late-surviving taxa and indicate that several characters thought to define these species should be reassessed. The partial cranium of B. arenosa, including portions of the basicranium, neurocranium, face, and lower jaw, was recently recovered from Uinta B sediments. While its morphology is consistent with known specimens of B. arenosa, we observed several distinct differences: a crescent-shaped condylus occipitalis that is concave dorsally, tuberculum basioccipitale that flare out laterally, and a distinct frontal-nasal suture. The current sample of plastral and carapacial morphology considerably expands the documented variation in the hypodigms of B. arenosa and C. undatum. Novel shell characters observed include sigmoidal extragular-humeral sulci, and small, subtriangular gular scutes. Subadult specimens reveal ontogenetic processes in both taxa, and demonstrate that diagnostic morphological differences between them were present from an early developmental age. PMID:28686718
Smith, Heather F; Hutchison, J Howard; Townsend, K E Beth; Adrian, Brent; Jager, Daniel
2017-01-01
We described newly discovered baenid specimens from the Uintan North American Land Mammal Age (NALMA), in the Uinta Formation, Uinta Basin, Utah. These specimens include a partial skull and several previously undescribed postcranial elements of Baena arenosa, and numerous well-preserved shells of B. arenosa and Chisternon undatum. Baenids from the Uintan NALMA (46.5-40 Ma) are critical in that they provide valuable insight into the morphology and evolution of the diverse and speciose baenid family near the end of its extensive radiation, just prior to the disappearance of this clade from the fossil record. These Uintan specimens greatly increase the known variation in these late-surviving taxa and indicate that several characters thought to define these species should be reassessed. The partial cranium of B. arenosa, including portions of the basicranium, neurocranium, face, and lower jaw, was recently recovered from Uinta B sediments. While its morphology is consistent with known specimens of B. arenosa, we observed several distinct differences: a crescent-shaped condylus occipitalis that is concave dorsally, tuberculum basioccipitale that flare out laterally, and a distinct frontal-nasal suture. The current sample of plastral and carapacial morphology considerably expands the documented variation in the hypodigms of B. arenosa and C. undatum. Novel shell characters observed include sigmoidal extragular-humeral sulci, and small, subtriangular gular scutes. Subadult specimens reveal ontogenetic processes in both taxa, and demonstrate that diagnostic morphological differences between them were present from an early developmental age.
García-Varela, Martín; García-Prieto, Luís; Rodríguez, Rodolfo Pérez
2011-12-01
The morphology of the males of Neoechinorhynchus schmidti (Acanthocephala: Neoechinorhynchidae) is unknown, because this species was described based exclusively on females. However, recently we collected 2 common slider turtles Trachemys scripta in Centla swamps, Tabasco, Mexico, parasitized by 27 specimens of an acanthocephalan whose females were morphologically identical to N. schmidti. The domains D2 and D3 of the large subunit of the nuclear ribosomal RNA (LSU) of 3 males and 2 females of this material were sequenced. The sequences of both sexes were identical, and based on this result, we described for the first time the morphology of the males of N. schmidti. In addition, 6 sequences of a congeneric species, also parasite of turtles (Neoechinorhynchus emyditoides) were generated in the current research. The 11 sequences of these 2 species were aligned with 13 sequences of another 4 species of the same genus, producing a data set of 24 taxa with 674 nucleotides. The genetic divergence between N. schmidti and N. emyditoides was 4% and intraspecific differences ranged from 0.01 to 0.02%. Pairwise differences between either of these species and 4 other congeners parasitic in fresh and brackish water fishes (Neoechinorhynchus golvani, Neoechinorhynchus roseum, Neoechinorhynchus saginatus, and Neoechinorhynchus sp.) varied from 9.5 to 33%. Maximum likelihood and maximum parsimony analyses show that N. schmidti and N. emyditoides are sister taxa. Bootstrap analysis also indicates that the sister relationship is reliably supported. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Daza-Criado, L; Hernández-Fernández, J
2014-02-21
Hawksbill sea turtles Eretmochelys imbricata are found extensively around the world, including the Atlantic, Pacific, and Indian Oceans; the Persian Gulf, and the Red and Mediterranean Seas. Populations of this species are affected by international trafficking of their shields, meat, and eggs, making it a critically endangered animal. We determined the haplotypes of 17 hawksbill foraging turtles of Islas del Rosario (Bolivar) and of the nesting beach Don Diego (Magdalena) in the Colombian Caribbean based on amplification and sequencing of the mitochondrial gene cytochrome oxidase c subunit I (COI). We identified 5 haplotypes, including EI-A1 previously reported in Puerto Rico, which was similar to 10 of the study samples. To our knowledge, the remaining 4 haplotypes have not been described. Samples EICOI11 and EICOI3 showed 0.2% divergence from EI-A1, by a single nucleotide change, and were classified as the EI-A2 haplotype. EICOI6, EICOI14, and EICOI12 samples showed 0.2% divergence from EI-A1 and 0.3% divergence from EI-A2 and were classified as EI-A3 haplotype. Samples EICOI16 and EICOI15 presented 5 nucleotide changes each and were classified as 2 different haplotypes, EI-A4 and EI-A5, respectively. The last 2 haplotypes had higher nucleotide diversity (K2P=1.7%) than that by the first 3 haplotypes. EI-A1 and EI-A2 occurred in nesting individuals, and EI-A2, EI-A3, EI-A4, and EI-A5 occurred in foraging individuals. The description of the haplotypes may be associated with reproductive migrations or foraging and could support the hypothesis of natal homing. Furthermore, they can be used in phylogeographic studies.
2012-01-01
Background Extant sauropsids (reptiles and birds) are divided into two major lineages, the lineage of Testudines (turtles) and Archosauria (crocodilians and birds) and the lineage of Lepidosauria (tuatara, lizards, worm lizards and snakes). Karyotypes of these sauropsidan groups generally consist of macrochromosomes and microchromosomes. In chicken, microchromosomes exhibit a higher GC-content than macrochromosomes. To examine the pattern of intra-genomic GC heterogeneity in lepidosaurian genomes, we constructed a cytogenetic map of the Japanese four-striped rat snake (Elaphe quadrivirgata) with 183 cDNA clones by fluorescence in situ hybridization, and examined the correlation between the GC-content of exonic third codon positions (GC3) of the genes and the size of chromosomes on which the genes were localized. Results Although GC3 distribution of snake genes was relatively homogeneous compared with those of the other amniotes, microchromosomal genes showed significantly higher GC3 than macrochromosomal genes as in chicken. Our snake cytogenetic map also identified several conserved segments between the snake macrochromosomes and the chicken microchromosomes. Cross-species comparisons revealed that GC3 of most snake orthologs in such macrochromosomal segments were GC-poor (GC3 < 50%) whereas those of chicken orthologs in microchromosomes were relatively GC-rich (GC3 ≥ 50%). Conclusion Our results suggest that the chromosome size-dependent GC heterogeneity had already occurred before the lepidosaur-archosaur split, 275 million years ago. This character was probably present in the common ancestor of lepidosaurs and but lost in the lineage leading to Anolis during the diversification of lepidosaurs. We also identified several genes whose GC-content might have been influenced by the size of the chromosomes on which they were harbored over the course of sauropsid evolution. PMID:23140509
Saka, Masahiro; Tada, Noriko; Kamata, Yoichi
2008-09-01
Vitellogenin (VTG), a yolk-precursor protein in oviparous vertebrates, is a useful biomarker for reproductive physiology and environmental estrogenic pollution. To examine interspecific applicability of an enzyme-linked immunosorbent assay (ELISA) for quantifying Chinemys reevesii VTG, we observed cross-reactivity between a polyclonal antibody against Chinemys reevesii VTG and the VTGs from other turtle species: Chelydra serpentina (Chelydridae), Macrochelys temminckii (Chelydridae), and Pelodiscus sinensis (Trionychidae), which are phylogenetically distant from Chinemys reevesii (Geoemydidae). The VTGs of the three species were induced by injecting estradiol 17beta into the turtles and purified by using the EDTA-MgCl(2) precipitation method. The purified VTG appeared as a 200-kDa protein in sodium dodecylsulfate polyacrylamide gel electrophoresis, indicating that the molecular mass of the VTGs of the three species was similar to that of Chinemys reevesii VTG. The purified VTGs were serially diluted (0.004-2 mug/ml) and applied to the ELISA. Although the VTGs of the two chelydrid turtles showed cross-reactivity in a concentration-dependent manner, the degree of cross-reactivity was only 22.8-41.2% (mean=30.0%) and 19.7-53.0% (mean=33.2%) for Chelydra serpentina VTG and Macrochelys temminckii VTG, respectively. The ELISA may therefore be theoretically applicable to measure relative levels of the VTGs of these two species, but the absolute concentration values may be inaccurate. Pelodiscus sinensis VTG showed almost no cross-reactivity (8.0-9.7%, mean=8.9%) at any concentration tested, thus indicating the inapplicability of the ELISA to quantify Pelodiscus sinensis VTG. There are thus limitations in extending the applicability of the ELISA across species, even within the order Testudines.
Schachner, E R; Sedlmayr, J C; Schott, R; Lyson, T R; Sanders, R K; Lambertz, M
2017-12-01
The common snapping turtle (Chelydra serpentina) is a well studied and broadly distributed member of Testudines; however, very little is known concerning developmental anomalies and soft tissue pathologies of turtles and other reptiles. Here, we present an unusual case of unilateral pulmonary aplasia, asymmetrical carapacial kyphosis, and mild scoliosis in a live adult C. serpentina. The detailed three-dimensional (3D) anatomy of the respiratory system in both the pathological and normal adult C. serpentina, and a hatchling are visualized using computed tomography (CT), microCT, and 3D digital anatomical models. In the pathological turtle, the right lung consists of an extrapulmonary bronchus that terminates in a blind stump with no lung present. The left lung is hyperinflated relative to the normal adult, occupying the extra coelomic space facilitated by the unusual mid-carapacial kyphotic bulge. The bronchial tree of the left lung retains the overall bauplan of the normal specimens, with some minor downstream variation in the number of secondary airways. The primary difference between the internal pulmonary structure of the pathological individual and that of a normal adult is a marked increase in the surface area and density of the parenchymal tissue originating from the secondary airways, a 14.3% increase in the surface area to volume ratio. Despite this, the aplasia has not had an impact upon the ability of the turtle to survive; however, it did interfere with aquatic locomotion and buoyancy control under water. This turtle represents a striking example of a non-fatal congenital defect and compensatory visceral hypertrophy. © 2017 Anatomical Society.
Vera, Vicente; Buitrago, Joaquín
2012-06-01
The second major nesting-site for green turtles in the Caribbean is Isla de Aves, an island protected as a wildlife refuge since 1972, located at 650km Northeast from La Guaira, Venezuela. In this island, the nesting population monitoring started in 1972 and in a more continuous way after 1978, when a Scientific-Naval Station was established and scientific observations started. Since historical data show that female captures had severely affected population levels in this island before 1978, this study aim to describe recent reproductive activities. For this, during the nesting seasons of 2001-2002 and 2005-2008, nesting females were measured and tagged using metal flipper tags. A total of 458 nights were sampled observing 5 154 female emergences, with a maximum of 53 in a single night. Non-observed emergences were calculated fitting the temporal distribution of observed emergences to a normal curve. Total emergences estimated varied from X=637.1+/-106.6 in 2001 to X =2 853+/-42.5 in 2008 (ANOVA F(6.5df)=60.37, p<0.0001). Internesting interval in the same season was estimated in X=10.71+/-1.32 days. Clutch frequency in a nesting season was calculated as X=1.71+/-1.6 times per female and season. Estimated number of nesting females per year varied from X=373+/-12.5 females in 2001 to X=l 669+/-56.1 females in 2008 (ANOVA F 55.6df)=89.42, p<0.0001); with a positive and significant trend (r=0.842, p=0.036). Results show that nesting females numbers are increasing. We suggest that the protection of the nesting area for more than 30 years, has contributed with this population increase.
Ferreira Júnior, P D; Castro, P T A
2010-02-01
Nest site has influence on incubation duration and hatching success of two Neotropical turtles, the giant Amazon River turtle (Podocnemis expansa) and yellow-spotted side-neck turtle (Podocnemis unifilis--'Tracajá'). The 2000 and 2001 nesting seasons have been monitored at the Javaés River in Bananal Island, Brazil. Although they nest on the same beaches, there is a separation of the nesting areas of P unifilis and P. expansa nests on the upper parts of the beach. The incubation duration for P. expansa is influenced by the nesting period, the height of the nest from the river, the clutch size, and the grain size in the site of the nest. Nests of Podocnemis expansa placed in coarse sediments have shorter incubation duration than those placed in finer sediments. The hatching success in P. expansa is influenced by grain size, incubation duration, and nesting period. The grain size is negatively correlated with hatching success, indicating that the nests situated in finer-grained sand have better chances of successful egg hatching than those in coarser-grained sand. Nests of the end of the reproductive season have lower hatching success and incubation duration than those at the start of the season. For P. unifilis, the nesting period and nest depth influence the incubation duration; moreover, the river dynamics significantly affect the hatching success. The oscillation of the river level and the moment of initial increase, the height of the nest from the river level, and the nesting period are all decisive components for hatching success. The results of this research show the importance of protecting areas with great geological diversity, wherein the features of the environment can affect the microenvironment of nests, with consequences on incubation duration and hatching success.
Ennen, Joshua R.; Kalis, Marley E.; Patterson, Adam L.; Kreiser, Brian R.; Lovich, Jeffrey E.; Godwin, James; Qualls, Carl P.
2014-01-01
Widely distributed species often display intraspecific morphological variation due to the abiotic and biotic gradients experienced across their ranges. Historically, in many vertebrate taxa, such as birds and reptiles, these morphological differences within a species were used to delimit subspecies. Graptemys nigrinoda is an aquatic turtle species endemic to the Mobile Bay Basin. Colour pattern and morphological variability were used to describe a subspecies (G. n. delticola) from the lower reaches of the system, although it and the nominate subspecies also reportedly intergrade over a large portion of the range. Other researchers have suggested that these morphological differences merely reflect clinal variation. Our molecular data (mtDNA) did not support the existence of the subspecies, as the haplotypes were differentiated by only a few base pairs and one haplotype was shared between the putative subspecies. While there were significant morphological and pattern differences among putative specimens of G. n. nigrinoda, G. n. delticola and G. n. nigrinoda × delticola, these differences probably represent clinal variation as they were also related to environmental variables [i.e. cumulative drainage area and drainage (categorical)]. Specimens occupying slow-current, high-turbidity river reaches (e.g. the Tensaw River) exhibited greater relative carapace heights and more dark pigmentation, while specimens occupying fast-current, clearer rivers (e.g. the upper Alabama, Cahaba and Tallapoosa rivers) exhibited lower carapace heights and more yellow pigmentation. Given the absence of clear molecular and morphological differences that are related to drainage characteristics, we suggest that there is not sufficient evidence for the recognition of G. n. delticola as a distinct subspecies.
Rabi, Márton; Zhou, Chang-Fu; Wings, Oliver; Ge, Sun; Joyce, Walter G
2013-09-22
Most turtles from the Middle and Late Jurassic of Asia are referred to the newly defined clade Xinjiangchelyidae, a group of mostly shell-based, generalized, small to mid-sized aquatic froms that are widely considered to represent the stem lineage of Cryptodira. Xinjiangchelyids provide us with great insights into the plesiomorphic anatomy of crown-cryptodires, the most diverse group of living turtles, and they are particularly relevant for understanding the origin and early divergence of the primary clades of extant turtles. Exceptionally complete new xinjiangchelyid material from the ?Qigu Formation of the Turpan Basin (Xinjiang Autonomous Province, China) provides new insights into the anatomy of this group and is assigned to Xinjiangchelys wusu n. sp. A phylogenetic analysis places Xinjiangchelys wusu n. sp. in a monophyletic polytomy with other xinjiangchelyids, including Xinjiangchelys junggarensis, X. radiplicatoides, X. levensis and X. latiens. However, the analysis supports the unorthodox, though tentative placement of xinjiangchelyids and sinemydids outside of crown-group Testudines. A particularly interesting new observation is that the skull of this xinjiangchelyid retains such primitive features as a reduced interpterygoid vacuity and basipterygoid processes. The homology of basipterygoid processes is confidently demonstrated based on a comprehensive review of the basicranial anatomy of Mesozoic turtles and a new nomenclatural system is introduced for the carotid canal system of turtles. The loss of the basipterygoid process and the bony enclosure of the carotid circulation system occurred a number of times independently during turtle evolution suggesting that the reinforcement of the basicranial region was essential for developing a rigid skull, thus paralleling the evolution of other amniote groups with massive skulls.
The Head and Neck Anatomy of Sea Turtles (Cryptodira: Chelonioidea) and Skull Shape in Testudines
Jones, Marc E. H.; Werneburg, Ingmar; Curtis, Neil; Penrose, Rod; O’Higgins, Paul; Fagan, Michael J.; Evans, Susan E.
2012-01-01
Background Sea turtles (Chelonoidea) are a charismatic group of marine reptiles that occupy a range of important ecological roles. However, the diversity and evolution of their feeding anatomy remain incompletely known. Methodology/Principal Findings Using computed tomography and classical comparative anatomy we describe the cranial anatomy in two sea turtles, the loggerhead (Caretta caretta) and Kemp’s ridley (Lepidochelys kempii), for a better understanding of sea turtle functional anatomy and morphological variation. In both taxa the temporal region of the skull is enclosed by bone and the jaw joint structure and muscle arrangement indicate that palinal jaw movement is possible. The tongue is relatively small, and the hyoid apparatus is not as conspicuous as in some freshwater aquatic turtles. We find several similarities between the muscles of C. caretta and L. kempii, but comparison with other turtles suggests only one of these characters may be derived: connection of the m. adductor mandibulae internus into the Pars intramandibularis via the Zwischensehne. The large fleshy origin of the m. adductor mandibulae externus Pars superficialis from the jugal seems to be a characteristic feature of sea turtles. Conclusions/Significance In C. caretta and L. kempii the ability to suction feed does not seem to be as well developed as that found in some freshwater aquatic turtles. Instead both have skulls suited to forceful biting. This is consistent with the observation that both taxa tend to feed on relatively slow moving but sometimes armoured prey. The broad fleshy origin of the m. adductor mandibulae externus Pars superficialis may be linked to thecheek region being almost fully enclosed in bone but the relationship is complex. PMID:23144831
Roberts, Jackson R; Halanych, Kenneth M; Arias, Cova R; Folt, Brian; Goessling, Jeffrey M; Bullard, Stephen A
2017-12-01
Hapalorhynchus Stunkard, 1922 is emended based on morphological study of existing museum specimens (type and voucher specimens) and newly-collected specimens infecting musk turtles (Testudines: Kinosternidae: Sternotherus spp.) from rivers in Alabama and Florida (USA). Hapalorhynchus conecuhensis n. sp. is described from an innominate musk turtle, Sternotherus cf. minor, (type host) from Blue Spring (31°5'27.64″N, 86°30'53.21″W; Pensacola Bay Basin, Alabama) and the loggerhead musk turtle, Sternotherus minor (Agassiz, 1857) from the Wacissa River (30°20'24.73″N, 83°59'27.56″W; Apalachee Bay Basin, Florida). It differs from congeners by lacking a body constriction at level of the ventral sucker, paired anterior caeca, and a transverse ovary as well as by having a small ventral sucker, proportionally short posterior caeca, nearly equally-sized anterior and posterior testes, a small cirrus sac, and a uterus extending dorsal to the ovary and the anterior testis. Specimens of Hapalorhynchus reelfooti Byrd, 1939 infected loggerhead musk turtles, stripe-necked musk turtles (Sternotherus peltifer Smith and Glass, 1947), Eastern musk turtles (Sternotherus odoratus [Latreille in Sonnini and Latreille, 1801]), and S. cf. minor. Those of Hapalorhynchus cf. stunkardi infected S. minor and S. odoratus. Sternothorus minor, S. peltifer, and S. cf. minor plus S. minor and S. odoratus are new host records for H. reelfooti and H. cf. stunkardi, respectively. This is the first report of an infected musk turtle from the Coosa and Tallapoosa Rivers (Mobile-Tensaw River Basin), Pensacola Bay Basin, or Apalachee Bay Basin. Sequence analysis of the large subunit rDNA (28S) showed a strongly-supported clade for Hapalorhynchus. Copyright © 2017 Elsevier B.V. All rights reserved.
2013-01-01
Background Most turtles from the Middle and Late Jurassic of Asia are referred to the newly defined clade Xinjiangchelyidae, a group of mostly shell-based, generalized, small to mid-sized aquatic froms that are widely considered to represent the stem lineage of Cryptodira. Xinjiangchelyids provide us with great insights into the plesiomorphic anatomy of crown-cryptodires, the most diverse group of living turtles, and they are particularly relevant for understanding the origin and early divergence of the primary clades of extant turtles. Results Exceptionally complete new xinjiangchelyid material from the ?Qigu Formation of the Turpan Basin (Xinjiang Autonomous Province, China) provides new insights into the anatomy of this group and is assigned to Xinjiangchelys wusu n. sp. A phylogenetic analysis places Xinjiangchelys wusu n. sp. in a monophyletic polytomy with other xinjiangchelyids, including Xinjiangchelys junggarensis, X. radiplicatoides, X. levensis and X. latiens. However, the analysis supports the unorthodox, though tentative placement of xinjiangchelyids and sinemydids outside of crown-group Testudines. A particularly interesting new observation is that the skull of this xinjiangchelyid retains such primitive features as a reduced interpterygoid vacuity and basipterygoid processes. Conclusions The homology of basipterygoid processes is confidently demonstrated based on a comprehensive review of the basicranial anatomy of Mesozoic turtles and a new nomenclatural system is introduced for the carotid canal system of turtles. The loss of the basipterygoid process and the bony enclosure of the carotid circulation system occurred a number of times independently during turtle evolution suggesting that the reinforcement of the basicranial region was essential for developing a rigid skull, thus paralleling the evolution of other amniote groups with massive skulls. PMID:24053145
Parham, James F.; Ehret, Dana J.; Ebersole, Jun A.
2018-01-01
Late Cretaceous members of Peritresius belong to a diverse clade of marine adapted turtles currently thought to be some of the earliest representatives of the lineage leading to modern hard-shelled sea turtles (Pan-Cheloniidae). Prior studies have suggested that Peritresius was monospecific, with a distribution restricted to Maastrichtian deposits in North America. However, new Peritresius specimens identified from Alabama and Mississippi, USA, show that the genus contains two taxa, Peritresius ornatus, and a new species Peritresius martini sp. nov. These two taxa are characterized by the presence of a generally cordiform carapace with moderately serrated peripherals, well-developed ventral flanges beginning at the third peripheral, squarish umbilical and lateral plastral fontanelles, and a narrow bridge formed by the contact between the hyoplastron and hypoplastron. Peritresius martini sp. nov. can be distinguished by its lack of dermal ornamentation and the presence of a ‘rib-free’ 10th peripheral. These new specimens represent the first occurrences of Peritresius from the Late Cretaceous Mississippi Embayment and extend the temporal range of this genus back to the early Campanian. When tested within a global phylogenetic context, Peritresius is placed on the stem of Cheloniidae (Pan-Cheloniidae) along with Ctenochelys and Allopleuron hofmanni. The heavily vascularized and uniquely sculptured dermal elements of P. ornatus are interpreted here as potentially relating to thermoregulation and therefore may have been one of the key factors contributing to the survival of Peritresius into the Maastrichtian, a period of cooling when other lineages of Campanian marine turtles (e.g., Protostegids, Toxochelys, and Ctenochelys) went extinct. PMID:29668704
Zenteno Ruiz, Claudia Elena; Barba Macias, Everardo; Bello-Gutiérrez, Joaquín; Ochoa-Gaona, Susana
2010-12-01
The Central American River Turtle (Dermatemys mawii) is an endangered species that has been poorly studied. There are no reports on their population status, habitat condition, and the species distribution area is still unknown. This study analyzes the seasonal and spatial variations of their habitat and the presence/absence of D. mawii in three rivers within the Pantanos de Centla Biosphere Reserve (Tabasco, Mexico). For habitat characterization, natural segmentation of rivers was used and three sites per segment were identified, 9 in each rivers (Grijalva and Usumacinta) and 6 in Tabasquillo. Additionally, the evaluation of 11 environmental variables such as water hydrological, physicochemical characteristics and riparian and hydrophytic vegetation were carried out during two different seasons (dry and rainy). The presence/absence of species was assessed with eight fike nets that were set per segment, with a capture effort of 384 hours per trap. The capture per unit effort (CPUE) was used as an indicator of relative abundance. The results indicated spatio-temporal variations in habitat characteristics and the presence of environmental gradients. The principal components analysis (PCA) applied allowed us to determine that the first three components explained 67.8% of the environmental variability. The species presence was confirmed in all rivers, however significant differences exists in their relative abundance: the highest was registered in the Tabasquillo River where the species was present in both seasons and in all segments. Of the 11 environmental variables analyzed, the gradient, shelter and depth were the most indicative of species presence. The obtained results evidenced the importance of riparian vegetation as habitat for Dermatemys. This represents the first approach towards an action plan for a species and its habitat protection within the Pantanos de Centla Biosphere Reserve.
Pantoja-Lima, Jackson; Aride, Paulo H R; de Oliveira, Adriano T; Félix-Silva, Daniely; Pezzuti, Juarez C B; Rebêlo, George H
2014-01-27
Consumption of turtles by natives and settlers in the Amazon and Orinoco has been widely studied in scientific communities. Accepted cultural customs and the local dietary and monetary needs need to be taken into account in conservation programs, and when implementing federal laws related to consumption and fishing methods. This study was conducted around the Purus River, a region known for the consumption and illegal trade of turtles. The objective of this study was to quantify the illegal turtle trade in Tapauá and to understand its effect on the local economy. This study was conducted in the municipality of Tapauá in the state of Amazonas, Brazil. To estimate turtle consumption, interviews were conducted over 2 consecutive years (2006 and 2007) in urban areas and isolated communities. The experimental design was randomized with respect to type of household. To study the turtle fishery and trade chain, we used snowball sampling methodology. During our study period, 100% of respondents reported consuming at least three species of turtles (Podocnemis spp.). Our estimates indicate that about 34 tons of animals are consumed annually in Tapauá along the margins of a major fishing river in the Amazon. At least five components related to the chain of commercialization of turtles on the Purus River are identified: Indigenous Apurinã and (2) residents of bordering villages (communities); (3) of local smugglers buy and sell turtles to the community in exchange for manufactured goods, and (4) regional smugglers buy in Tapauá, Lábrea, and Beruri to sell in Manaus and Manacapuru; Finally, (5) there are professional fishermen. We quantify the full impact of turtle consumption and advocate the conservation of the region's turtle populations. The Brazilian government should initiate a new turtle consumption management program which involves the opinions of consumers. With these measures the conservation of freshwater turtles in the Brazilian Amazon, is possible.
Di Ianni, Francesco; Merli, Elisa; Burtini, Francesca; Conti, Virna; Pelizzone, Igor; Di Lecce, Rosanna; Parmigiani, Enrico; Squassino, Gian Paolo; Del Bue, Maurizio; Lucarelli, Enrico; Ramoni, Roberto; Grolli, Stefano
2015-01-01
Platelet concentrates are widely used in mammalian regenerative medicine to improve tissue healing. Chelonians (Testudines) would benefit from the application of thrombocyte preparations to regenerate damaged tissues, since traumatic injuries are leading causes of morbidity and mortality for both wild-living and domesticated animals. The aim of this study was to establish a protocol that optimized the recovery of the thrombocytes from blood samples and to show the efficacy of thrombocyte-enriched plasma in chelonians. Peripheral blood samples were obtained from Testudo spp. (n = 12) and Trachemys scripta elegans (n = 10). Blood cells were fractionated by sodium diatrizoate-sodium polysucrose density gradient using a two-step centrifugation protocol. Thrombocytes and leukocytes were isolated and resuspended to obtain thrombocyte-leucocyte rich plasma (TLRP). The mean recovery of leukocytes and thrombocytes was 48.9% (±4.0 SEM, n = 22) of the whole blood cell content. No statistically significant difference was observed between blood samples collected from different turtle species. The ability of TLRP to form a gel was evaluated by adding variable concentrations of calcium gluconate at room temperature and at 37°C. A reliable and consistent clotting of the TLRP was obtained in glass tubes and dishes by adding 5-20% v/v of a 100 mg/ml solution of calcium gluconate. Furthermore, in order to test the clinical efficacy of TLRP, a preliminary evaluation was performed on four turtles (Testudo spp.) with traumatic injuries. In all the four animals, a successful clinical outcome was observed. The results demonstrated that a thrombocyte-enriched plasma, comparable to mammalian platelet rich plasma, can be prepared from chelonian blood samples. Furthermore, although the low number of cases presented does not allow definitive conclusions from a clinical point of view, their outcome suggests that TLRP application could be further investigated to improve the healing process of both soft and hard tissue injuries in chelonians. PMID:25901960
Reptilia: Testudines: Emydidae Graptemys gibbonsi - Pascagoula Map Turtle
Lovich, Jeffrey E.; Ennen, Joshua R.
2014-01-01
The Pascagoula Map Turtle, Graptemys gibbonsi, is a large riverine species that exhibits pronounced sexual dimorphism, where females attain a maximum carapace length (CL) of 295 mm and males a maximum of 141 mm (Lovich et al. 2009). Mean adult female CL (248 mm) can be well over twice the mean CL of adult males (104 mm; Gibbons and Lovich 1990, Lovich et al. 2009). In addition, females have conspicuously enlarged heads (37.9 mm, SD = 14.0 mm) with broad alveolar surfaces (12.1 mm, SD = 4.9) compared to males (head width – 16.4 mm, SD = 1.1 mm; alveolar width – 4.3 mm, SD = 0.40 mm; Lindeman, unpublished data). Males have longer tails with the vent posterior to the edge of the carapace. Both sexes have relatively flat plastrons. Similar to other species within the pulchra clade, Graptemys gibbonsi possess a high-domed shell with a median keel. The median carapace keel is composed of prominent spines on the posterior portions of the second and third vertebrals. A broken black stripe, most pronounced anteriorly, marks the median keel of the vertebrals, and pleural scutes 1– 3 have a network of intersecting yellow lines or circular yellow markings on the distal parts. The plastron is pale yellow with dark pigment on some seams. Ground color of the head and limbs is brown to olive with light yellow or yellowish-green stripes and blotches. The yellow pigment on the upper marginal scutes is wide in comparison to other members of the pulchra clade.Hatchling pigmentation patterns resemble those of adults, but with more conspicuous patterns on the pleural scutes. Similarly, the plastron of hatchlings commonly has more dark pigmentation along the seams than adults. The shell is highly serrated along the edge of the carapace and the vertebral keel is more pronounced than in adults.
Nesting ecology of Chelonia mydas (Testudines: Cheloniidae) on the Guanahacabibes Peninsula, Cuba.
Azanza Ricardo, Julia; Ibarra Martín, Maria E; González Sansón, Gaspar; Abreu Grobois, F Alberto; Eckert, Karen L; Espinosa López, Georgina; Oyama, Ken
2013-12-01
The nesting colony of green sea turtles (Chelonia mydas) at Guanahacabibes Peninsula Biosphere Reserve and National Park is one of the largest in the Cuban archipelago; however, little information about its nesting ecology is available. Temporal and spatial variation in nesting and reproductive success as well as morphometric characteristics of gravid females were used to ecologically characterize this colony. Nine beaches of the Southernmost coast of Guanahacabibes Peninsula were monitored for 14 years (1998-2012) to determine green turtle nesting activity, from May to September (peak nesting season in this area). Beach dimensions were measured to determine nest density using the length and the area. Afterward the beaches were divided in two categories, index and secondary. Females were measured and tagged to compare new tagged females (823) with returning tagged females (140). Remigration interval was also determined. Temporal variation was identified as the annual number of nesting emergences and oviposits per female, with apparent peaks in reproductive activity on a biennial cycle in the first six years followed by periods of annual increase in nest number (2003-2008) and periods of decreasing number of nests (2010-2012). We also found intra-seasonal variation with the highest nesting activity in July, particularly in the second half of the month. The peak emergence time was 22:00-02:00 hr. In terms of spatial variation, smaller beaches had the highest nest density and nesting was more frequent 6-9m from the high tide line, where hatchling production was maximized although hatchling success was high on average, above 80%. Morphometric analysis of females was made and newly tagged turtles were smaller on average than remigrants. Our results are only a first attempt at characterizing Guanahacabibes' populations but have great value for establishing conservation priorities within the context of national management plans, and for efficient monitoring and protection of nesting beaches.
2014-01-01
Background Consumption of turtles by natives and settlers in the Amazon and Orinoco has been widely studied in scientific communities. Accepted cultural customs and the local dietary and monetary needs need to be taken into account in conservation programs, and when implementing federal laws related to consumption and fishing methods. This study was conducted around the Purus River, a region known for the consumption and illegal trade of turtles. The objective of this study was to quantify the illegal turtle trade in Tapauá and to understand its effect on the local economy. Methods This study was conducted in the municipality of Tapauá in the state of Amazonas, Brazil. To estimate turtle consumption, interviews were conducted over 2 consecutive years (2006 and 2007) in urban areas and isolated communities. The experimental design was randomized with respect to type of household. To study the turtle fishery and trade chain, we used snowball sampling methodology. Results During our study period, 100% of respondents reported consuming at least three species of turtles (Podocnemis spp.). Our estimates indicate that about 34 tons of animals are consumed annually in Tapauá along the margins of a major fishing river in the Amazon. At least five components related to the chain of commercialization of turtles on the Purus River are identified: Indigenous Apurinã and (2) residents of bordering villages (communities); (3) of local smugglers buy and sell turtles to the community in exchange for manufactured goods, and (4) regional smugglers buy in Tapauá, Lábrea, and Beruri to sell in Manaus and Manacapuru; Finally, (5) there are professional fishermen. Conclusions We quantify the full impact of turtle consumption and advocate the conservation of the region’s turtle populations. The Brazilian government should initiate a new turtle consumption management program which involves the opinions of consumers. With these measures the conservation of freshwater turtles in the Brazilian Amazon, is possible. PMID:24467796
Zheng, Chenfei; Nie, Liuwang; Wang, Jue; Zhou, Huaxing; Hou, Huazhen; Wang, Hao; Liu, Juanjuan
2013-01-01
Complete mitochondrial (mt) genome sequences with duplicate control regions (CRs) have been detected in various animal species. In Testudines, duplicate mtCRs have been reported in the mtDNA of the Asian big-headed turtle, Platysternon megacephalum, which has three living subspecies. However, the evolutionary pattern of these CRs remains unclear. In this study, we report the completed sequences of duplicate CRs from 20 individuals belonging to three subspecies of this turtle and discuss the micro-evolutionary analysis of the evolution of duplicate CRs. Genetic distances calculated with MEGA 4.1 using the complete duplicate CR sequences revealed that within turtle subspecies, genetic distances between orthologous copies from different individuals were 0.63% for CR1 and 1.2% for CR2app:addword:respectively, and the average distance between paralogous copies of CR1 and CR2 was 4.8%. Phylogenetic relationships were reconstructed from the CR sequences, excluding the variable number of tandem repeats (VNTRs) at the 3' end using three methods: neighbor-joining, maximum likelihood algorithm, and Bayesian inference. These data show that any two CRs within individuals were more genetically distant from orthologous genes in different individuals within the same subspecies. This suggests independent evolution of the two mtCRs within each P. megacephalum subspecies. Reconstruction of separate phylogenetic trees using different CR components (TAS, CD, CSB, and VNTRs) suggested the role of recombination in the evolution of duplicate CRs. Consequently, recombination events were detected using RDP software with break points at ≈290 bp and ≈1,080 bp. Based on these results, we hypothesize that duplicate CRs in P. megacephalum originated from heterological ancestral recombination of mtDNA. Subsequent recombination could have resulted in homogenization during independent evolutionary events, thus maintaining the functions of duplicate CRs in the mtDNA of P. megacephalum.
Zheng, Chenfei; Nie, Liuwang; Wang, Jue; Zhou, Huaxing; Hou, Huazhen; Wang, Hao; Liu, Juanjuan
2013-01-01
Complete mitochondrial (mt) genome sequences with duplicate control regions (CRs) have been detected in various animal species. In Testudines, duplicate mtCRs have been reported in the mtDNA of the Asian big-headed turtle, Platysternon megacephalum, which has three living subspecies. However, the evolutionary pattern of these CRs remains unclear. In this study, we report the completed sequences of duplicate CRs from 20 individuals belonging to three subspecies of this turtle and discuss the micro-evolutionary analysis of the evolution of duplicate CRs. Genetic distances calculated with MEGA 4.1 using the complete duplicate CR sequences revealed that within turtle subspecies, genetic distances between orthologous copies from different individuals were 0.63% for CR1 and 1.2% for CR2app:addword:respectively, and the average distance between paralogous copies of CR1 and CR2 was 4.8%. Phylogenetic relationships were reconstructed from the CR sequences, excluding the variable number of tandem repeats (VNTRs) at the 3′ end using three methods: neighbor-joining, maximum likelihood algorithm, and Bayesian inference. These data show that any two CRs within individuals were more genetically distant from orthologous genes in different individuals within the same subspecies. This suggests independent evolution of the two mtCRs within each P. megacephalum subspecies. Reconstruction of separate phylogenetic trees using different CR components (TAS, CD, CSB, and VNTRs) suggested the role of recombination in the evolution of duplicate CRs. Consequently, recombination events were detected using RDP software with break points at ≈290 bp and ≈1,080 bp. Based on these results, we hypothesize that duplicate CRs in P. megacephalum originated from heterological ancestral recombination of mtDNA. Subsequent recombination could have resulted in homogenization during independent evolutionary events, thus maintaining the functions of duplicate CRs in the mtDNA of P. megacephalum. PMID:24367563
Nagy, Zoltán T; Sonet, Gontran; Glaw, Frank; Vences, Miguel
2012-01-01
DNA barcoding of non-avian reptiles based on the cytochrome oxidase subunit I (COI) gene is still in a very early stage, mainly due to technical problems. Using a newly developed set of reptile-specific primers for COI we present the first comprehensive study targeting the entire reptile fauna of the fourth-largest island in the world, the biodiversity hotspot of Madagascar. Representatives of the majority of Madagascan non-avian reptile species (including Squamata and Testudines) were sampled and successfully DNA barcoded. The new primer pair achieved a constantly high success rate (72.7-100%) for most squamates. More than 250 species of reptiles (out of the 393 described ones; representing around 64% of the known diversity of species) were barcoded. The average interspecific genetic distance within families ranged from a low of 13.4% in the Boidae to a high of 29.8% in the Gekkonidae. Using the average genetic divergence between sister species as a threshold, 41-48 new candidate (undescribed) species were identified. Simulations were used to evaluate the performance of DNA barcoding as a function of completeness of taxon sampling and fragment length. Compared with available multi-gene phylogenies, DNA barcoding correctly assigned most samples to species, genus and family with high confidence and the analysis of fewer taxa resulted in an increased number of well supported lineages. Shorter marker-lengths generally decreased the number of well supported nodes, but even mini-barcodes of 100 bp correctly assigned many samples to genus and family. The new protocols might help to promote DNA barcoding of reptiles and the established library of reference DNA barcodes will facilitate the molecular identification of Madagascan reptiles. Our results might be useful to easily recognize undescribed diversity (i.e. novel taxa), to resolve taxonomic problems, and to monitor the international pet trade without specialized expert knowledge.
Nagy, Zoltán T.; Sonet, Gontran; Glaw, Frank; Vences, Miguel
2012-01-01
Background DNA barcoding of non-avian reptiles based on the cytochrome oxidase subunit I (COI) gene is still in a very early stage, mainly due to technical problems. Using a newly developed set of reptile-specific primers for COI we present the first comprehensive study targeting the entire reptile fauna of the fourth-largest island in the world, the biodiversity hotspot of Madagascar. Methodology/Principal Findings Representatives of the majority of Madagascan non-avian reptile species (including Squamata and Testudines) were sampled and successfully DNA barcoded. The new primer pair achieved a constantly high success rate (72.7–100%) for most squamates. More than 250 species of reptiles (out of the 393 described ones; representing around 64% of the known diversity of species) were barcoded. The average interspecific genetic distance within families ranged from a low of 13.4% in the Boidae to a high of 29.8% in the Gekkonidae. Using the average genetic divergence between sister species as a threshold, 41–48 new candidate (undescribed) species were identified. Simulations were used to evaluate the performance of DNA barcoding as a function of completeness of taxon sampling and fragment length. Compared with available multi-gene phylogenies, DNA barcoding correctly assigned most samples to species, genus and family with high confidence and the analysis of fewer taxa resulted in an increased number of well supported lineages. Shorter marker-lengths generally decreased the number of well supported nodes, but even mini-barcodes of 100 bp correctly assigned many samples to genus and family. Conclusions/Significance The new protocols might help to promote DNA barcoding of reptiles and the established library of reference DNA barcodes will facilitate the molecular identification of Madagascan reptiles. Our results might be useful to easily recognize undescribed diversity (i.e. novel taxa), to resolve taxonomic problems, and to monitor the international pet trade without specialized expert knowledge. PMID:22479636
Spanier, Matthew J
2010-12-01
Leatherback sea turtles (Dermochelys coriacea) nest on dynamic, erosion-prone beaches. Erosive processes and resulting nest loss have long been presumed to be a hindrance to clutch survival. In order to better understand how leatherbacks cope with unstable nesting beaches, I investigated the role of beach erosion in leatherback nest site selection at Playa Gandoca, Costa Rica. I also examined the potential effect of nest relocation, a conservation strategy in place at Playa Gandoca to prevent nest loss to erosion, on the temperature of incubating clutches. I monitored changes in beach structure as a result of erosion at natural nest sites during the time the nest was laid, as well as in subsequent weeks. To investigate slope as a cue for nest site selection, I measured the slope of the beach where turtles ascended from the sea to nest, as well as the slopes at other random locations on the beach for comparison. I examined temperature differences between natural and relocated nest sites with thermocouples placed in the sand at depths typical of leatherback nests. Nests were distributed non-randomly in a clumped distribution along the length of the beach and laid at locations that were not undergoing erosion. The slope at nest sites was significantly different than at randomly chosen locations on the beach. The sand temperature at nest depths was significantly warmer at natural nest sites than at locations of relocated nests. The findings of this study suggest leatherbacks actively select nest sites that are not undergoing erosive processes, with slope potentially being used as a cue for site selection. The relocation of nests appears to be inadvertently cooling the nest environment. Due to the fact that leatherback clutches undergo temperature-dependent sex determination, the relocation of nests may be producing an unnatural male biasing of hatchlings. The results of this study suggest that the necessity of relocation practices, largely in place to protect nests from erosion, should be reevaluated to ensure the proper conservation of this critically endangered species.
Alves, Rômulo RN; Santana, Gindomar G
2008-01-01
Background Throughout Brazil a large number of people seek out reptiles for their meat, leather, ornamental value and supposed medicinal importance. However, there is a dearth of information on the use of reptiles in folk medicine. In North Brazil, the freshwater turtle, Podocnemis expansa, is one of the most frequently used species in traditional medicines. Many products derived from P. expansa are utilized in rural areas and also commercialized in outdoor markets as a cure or treatment for different diseases. Here we document the use and commercialization of P. expansa for medicinal purposes in the state of Pará, Northern Brazil. Methods Data were gathered through interview-questionnaires, with some questions left open-ended. Information was collected in two localities in Pará State, North of Brazil. In the City of Belém, data was collected through interviews with 23 herbs or root sellers (13 men and 10 women). Attempts were made to interview all animal merchants in the markets visited. In fishing community of the Pesqueiro Beach, interviews were done with 41 inhabitants (23 men and 18 women) and during the first contacts with the local population, we attempted to identify local people with a specialized knowledge of medicinal animal usage. Results P. expansa was traded for use in traditional medicines and cosmetics. Fat and egg shells were used to treat 16 different diseases. Turtle fat was the main product sold. The demand for these products is unknown. However, the use of this species in folk medicine might have a considerable impact on wild population, and this must be taken into account for the conservation and management of this species. Conclusion Our results indicated that the use and commercialization of P. expansa products for medicinal purposes is common in North of Brazil. More studies regarding the use and commerce of Brazilian turtles are urgently needed in order to evaluate the real impact of such activities on natural populations. We hope that our findings about the trade and use of P. expansa in folk medicine will motivate further studies on the use of animals in folk medicine and its implications for conservation. PMID:18208597
A toothed turtle from the Late Jurassic of China and the global biogeographic history of turtles.
Joyce, Walter G; Rabi, Márton; Clark, James M; Xu, Xing
2016-10-28
Turtles (Testudinata) are a successful lineage of vertebrates with about 350 extant species that inhabit all major oceans and landmasses with tropical to temperate climates. The rich fossil record of turtles documents the adaptation of various sub-lineages to a broad range of habitat preferences, but a synthetic biogeographic model is still lacking for the group. We herein describe a new species of fossil turtle from the Late Jurassic of Xinjiang, China, Sichuanchelys palatodentata sp. nov., that is highly unusual by plesiomorphically exhibiting palatal teeth. Phylogenetic analysis places the Late Jurassic Sichuanchelys palatodentata in a clade with the Late Cretaceous Mongolochelys efremovi outside crown group Testudines thereby establishing the prolonged presence of a previously unrecognized clade of turtles in Asia, herein named Sichuanchelyidae. In contrast to previous hypotheses, M. efremovi and Kallokibotion bajazidi are not found within Meiolaniformes, a clade that is here reinterpreted as being restricted to Gondwana. A revision of the global distribution of fossil and recent turtle reveals that the three primary lineages of derived, aquatic turtles, including the crown, Paracryptodira, Pan-Pleurodira, and Pan-Cryptodira can be traced back to the Middle Jurassic of Euramerica, Gondwana, and Asia, respectively, which resulted from the primary break up of Pangaea at that time. The two primary lineages of Pleurodira, Pan-Pelomedusoides and Pan-Chelidae, can similarly be traced back to the Cretaceous of northern and southern Gondwana, respectively, which were separated from one another by a large desert zone during that time. The primary divergence of crown turtles was therefore driven by vicariance to the primary freshwater aquatic habitat of these lineages. The temporally persistent lineages of basal turtles, Helochelydridae, Meiolaniformes, Sichuanchelyidae, can similarly be traced back to the Late Mesozoic of Euramerica, southern Gondwana, and Asia. Given the ambiguous phylogenetic relationships of these three lineages, it is unclear if their diversification was driven by vicariance as well, or if they display a vicariance-like pattern. The clean, primary signal apparent among early turtles is secondarily obliterated throughout the Late Cretaceous to Recent by extensive dispersal of continental turtles and by multiple invasions of marine habitats.
Li, H; Liu, J; Xiong, L; Zhang, H; Zhou, H; Yin, H; Jing, W; Li, J; Shi, Q; Wang, Y; Liu, J; Nie, L
2017-05-01
The softshell turtles (Trionychidae) are one of the most widely distributed reptile groups in the world, and fossils have been found on all continents except Antarctica. The phylogenetic relationships among members of this group have been previously studied; however, disagreements regarding its taxonomy, its phylogeography and divergence times are still poorly understood as well. Here, we present a comprehensive mitogenomic study of softshell turtles. We sequenced the complete mitochondrial genomes of 10 softshell turtles, in addition to the GenBank sequence of Dogania subplana, Lissemys punctata, Trionyx triunguis, which cover all extant genera within Trionychidae except for Cyclanorbis and Cycloderma. These data were combined with other mitogenomes of turtles for phylogenetic analyses. Divergence time calibration and ancestral reconstruction were calculated using BEAST and RASP software, respectively. Our phylogenetic analyses indicate that Trionychidae is the sister taxon of Carettochelyidae, and support the monophyly of Trionychinae and Cyclanorbinae, which is consistent with morphological data and molecular analysis. Our phylogenetic analyses have established a sister taxon relationship between the Asian Rafetus and the Asian Palea + Pelodiscus + Dogania + Nilssonia + Amyda, whereas a previous study grouped the Asian Rafetus with the American Apalone. The results of divergence time estimates and area ancestral reconstruction show that extant Trionychidae originated in Asia at around 108 million years ago (MA), and radiations mainly occurred during two warm periods, namely Late Cretaceous-Early Eocene and Oligocene. By combining the estimated divergence time and the reconstructed ancestral area of softshell turtles, we determined that the dispersal of softshell turtles out of Asia may have taken three routes. Furthermore, the times of dispersal seem to be in agreement with the time of the India-Asia collision and opening of the Bering Strait, which provide evidence for the accuracy of our estimation of divergence time. Overall, the mitogenomes of this group were used to explore the origin and dispersal route of Trionychidae and have provided new insights on the evolution of this group. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.
Alves, Rômulo R N; Santana, Gindomar G
2008-01-21
Throughout Brazil a large number of people seek out reptiles for their meat, leather, ornamental value and supposed medicinal importance. However, there is a dearth of information on the use of reptiles in folk medicine. In North Brazil, the freshwater turtle, Podocnemis expansa, is one of the most frequently used species in traditional medicines. Many products derived from P. expansa are utilized in rural areas and also commercialized in outdoor markets as a cure or treatment for different diseases. Here we document the use and commercialization of P. expansa for medicinal purposes in the state of Pará, Northern Brazil. Data were gathered through interview-questionnaires, with some questions left open-ended. Information was collected in two localities in Pará State, North of Brazil. In the City of Belém, data was collected through interviews with 23 herbs or root sellers (13 men and 10 women). Attempts were made to interview all animal merchants in the markets visited. In fishing community of the Pesqueiro Beach, interviews were done with 41 inhabitants (23 men and 18 women) and during the first contacts with the local population, we attempted to identify local people with a specialized knowledge of medicinal animal usage. P. expansa was traded for use in traditional medicines and cosmetics. Fat and egg shells were used to treat 16 different diseases. Turtle fat was the main product sold. The demand for these products is unknown. However, the use of this species in folk medicine might have a considerable impact on wild population, and this must be taken into account for the conservation and management of this species. Our results indicated that the use and commercialization of P. expansa products for medicinal purposes is common in North of Brazil. More studies regarding the use and commerce of Brazilian turtles are urgently needed in order to evaluate the real impact of such activities on natural populations. We hope that our findings about the trade and use of P. expansa in folk medicine will motivate further studies on the use of animals in folk medicine and its implications for conservation.
2013-01-01
Background The use of ethnoecological tools to evaluate possible damage and loss of biodiversity related to the populations of species under some degree of threat may represent a first step towards integrating the political management of natural resources and conservation strategies. From this perspective, this study investigates fishermen’s ecological knowledge about sea turtles and attitudes towards the conservation and bycatch in Ilhéus, Southern Bahia, Brazil. Methods Fishermen experts semi-structured interviews were performed using snowball sampling method. The interviews consisted of a series of questions relating to the fishermen’s profile, structure and work equipment, the local ecological knowledge of fishermen about sea turtles and bycatch, a projective test, attitudes towards turtle conservation and beliefs and taboos regarding turtles. Indicators for quantitative comparisons of respondents in terms of their broad knowledge and attitudes towards turtle conservation were created. Correlation analyses were made between indicators of knowledge and attitude as well as the relationship between education level and knowledge and attitudes. Results Thirty experts were interviewed for the study. The local ecological knowledge and attitudes of fishermen towards the conservation of sea turtles were respectively medium (0.43) and moderate (0.69) according to experts (based on Likert scale and Cronbach’s Alpha). Potential areas of spawning were reported from Barra Grande to Una covering the entire coast of Ilhéus. Methods for identifying the animal, behavior, and popular names were described by fishermen. The most recent captures of turtles were attributed to fishing line, but according to the respondents, lobster nets and shrimp traps are more likely to capture turtles. Knowledge and attitudes were weakly inversely correlated (r = −0.38, p = 0.04), and the education level of the respondent showed a positive correlation with positive attitudes towards turtle conservation (H = 8.33; p = 0.04). Life history, habitat, specific and exogenous taboos, beliefs and the use of hawksbill turtle to make glasses and other handcrafts are also reported in the study. Conclusions Monitoring of spawning areas, preservation of traditional practices, strategies to moderate the use of fishery resources and the local ecological knowledge/attitudes can provide data to improve the conservation practices and management of sea turtles. PMID:23448503
Zazhigin, Vladimir S.
2017-01-01
Background The present-day amphibian and reptile fauna of Western Siberia are the least diverse of the Palaearctic Realm, as a consequence of the unfavourable climatic conditions that predominate in this region. The origin and emergence of these herpetofaunal groups are poorly understood. Aside from the better-explored European Neogene localities yielding amphibian and reptile fossil remains, the Neogene herpetofauna of Western Asia is understudied. The few available data need critical reviews and new interpretations, taking into account the more recent records of the European herpetofauna. The comparison of this previous data with that of European fossil records would provide data on palaeobiogeographic affiliations of the region as well as on the origin and emergence of the present-day fauna of Western Siberia. An overview of the earliest occurrences of certain amphibian lineages is still needed. In addition, studies that address such knowledge gaps can be useful for molecular biologists in their calibration of molecular clocks. Methods and Results In this study, we considered critically reviewed available data from amphibian and reptile fauna from over 40 Western Siberian, Russian and Northeastern Kazakhstan localities, ranging from the Middle Miocene to Early Pleistocene. Herein, we provided new interpretations that arose from our assessment of the previously published and new data. More than 50 amphibians and reptile taxa were identified belonging to families Hynobiidae, Cryptobranchidae, Salamandridae, Palaeobatrachidae, Bombinatoridae, Pelobatidae, Hylidae, Bufonidae, Ranidae, Gekkonidae, Lacertidae, and Emydidae. Palaeobiogeographic analyses were performed for these groups and palaeoprecipitation values were estimated for 12 localities, using the bioclimatic analysis of herpetofaunal assemblages. Conclusion The Neogene assemblage of Western Siberia was found to be dominated by groups of European affinities, such as Palaeobatrachidae, Bombina, Hyla, Bufo bufo, and a small part of this assemblage included Eastern Palaearctic taxa (e.g. Salamandrella, Tylototriton, Bufotes viridis). For several taxa (e.g. Mioproteus, Hyla, Bombina, Rana temporaria), the Western Siberian occurrences represented their most eastern Eurasian records. The most diverse collection of fossil remains was found in the Middle Miocene. Less diversity has been registered towards the Early Pleistocene, potentially due to the progressive cooling of the climate in the Northern Hemisphere. The results of our study showed higher-amplitude changes of precipitation development in Western Siberia from the Early Miocene to the Pliocene, than previously assumed. PMID:28348925
Vasilyan, Davit; Zazhigin, Vladimir S; Böhme, Madelaine
2017-01-01
The present-day amphibian and reptile fauna of Western Siberia are the least diverse of the Palaearctic Realm, as a consequence of the unfavourable climatic conditions that predominate in this region. The origin and emergence of these herpetofaunal groups are poorly understood. Aside from the better-explored European Neogene localities yielding amphibian and reptile fossil remains, the Neogene herpetofauna of Western Asia is understudied. The few available data need critical reviews and new interpretations, taking into account the more recent records of the European herpetofauna. The comparison of this previous data with that of European fossil records would provide data on palaeobiogeographic affiliations of the region as well as on the origin and emergence of the present-day fauna of Western Siberia. An overview of the earliest occurrences of certain amphibian lineages is still needed. In addition, studies that address such knowledge gaps can be useful for molecular biologists in their calibration of molecular clocks. In this study, we considered critically reviewed available data from amphibian and reptile fauna from over 40 Western Siberian, Russian and Northeastern Kazakhstan localities, ranging from the Middle Miocene to Early Pleistocene. Herein, we provided new interpretations that arose from our assessment of the previously published and new data. More than 50 amphibians and reptile taxa were identified belonging to families Hynobiidae, Cryptobranchidae, Salamandridae, Palaeobatrachidae, Bombinatoridae, Pelobatidae, Hylidae, Bufonidae, Ranidae, Gekkonidae, Lacertidae, and Emydidae. Palaeobiogeographic analyses were performed for these groups and palaeoprecipitation values were estimated for 12 localities, using the bioclimatic analysis of herpetofaunal assemblages. The Neogene assemblage of Western Siberia was found to be dominated by groups of European affinities, such as Palaeobatrachidae, Bombina, Hyla , Bufo bufo , and a small part of this assemblage included Eastern Palaearctic taxa (e.g. Salamandrella , Tylototriton , Bufotes viridis ). For several taxa (e.g. Mioproteus, Hyla, Bombina , Rana temporaria ), the Western Siberian occurrences represented their most eastern Eurasian records. The most diverse collection of fossil remains was found in the Middle Miocene. Less diversity has been registered towards the Early Pleistocene, potentially due to the progressive cooling of the climate in the Northern Hemisphere. The results of our study showed higher-amplitude changes of precipitation development in Western Siberia from the Early Miocene to the Pliocene, than previously assumed.
Braga, Heitor de Oliveira; Schiavetti, Alexandre
2013-03-01
The use of ethnoecological tools to evaluate possible damage and loss of biodiversity related to the populations of species under some degree of threat may represent a first step towards integrating the political management of natural resources and conservation strategies. From this perspective, this study investigates fishermen's ecological knowledge about sea turtles and attitudes towards the conservation and bycatch in Ilhéus, Southern Bahia, Brazil. Fishermen experts semi-structured interviews were performed using snowball sampling method. The interviews consisted of a series of questions relating to the fishermen's profile, structure and work equipment, the local ecological knowledge of fishermen about sea turtles and bycatch, a projective test, attitudes towards turtle conservation and beliefs and taboos regarding turtles. Indicators for quantitative comparisons of respondents in terms of their broad knowledge and attitudes towards turtle conservation were created. Correlation analyses were made between indicators of knowledge and attitude as well as the relationship between education level and knowledge and attitudes. Thirty experts were interviewed for the study. The local ecological knowledge and attitudes of fishermen towards the conservation of sea turtles were respectively medium (0.43) and moderate (0.69) according to experts (based on Likert scale and Cronbach's Alpha). Potential areas of spawning were reported from Barra Grande to Una covering the entire coast of Ilhéus. Methods for identifying the animal, behavior, and popular names were described by fishermen. The most recent captures of turtles were attributed to fishing line, but according to the respondents, lobster nets and shrimp traps are more likely to capture turtles. Knowledge and attitudes were weakly inversely correlated (r = -0.38, p = 0.04), and the education level of the respondent showed a positive correlation with positive attitudes towards turtle conservation (H = 8.33; p = 0.04). Life history, habitat, specific and exogenous taboos, beliefs and the use of hawksbill turtle to make glasses and other handcrafts are also reported in the study. Monitoring of spawning areas, preservation of traditional practices, strategies to moderate the use of fishery resources and the local ecological knowledge/attitudes can provide data to improve the conservation practices and management of sea turtles.