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Sample records for amphisbaenidae squamata amphisbaenia

  1. The homology of the pelvic elements of Zygaspis quadrifrons (Squamata: Amphisbaenia).

    PubMed

    Urben, Carling C; Daza, Juan D; Cadena, Cristhian; Lewis, Patrick J; Thies, Monte L

    2014-08-01

    Limb attenuation with element loss has occurred multiple times among the Squamata (lizards, snakes, and amphisbaenians). Although most of the attention has been focused on the appendicular bones, we found that the pelvic rudiments have been studied less thoroughly and recurring disagreement is common among different authors studying the same species. We studied the osteology of the pelvic region of female and male Zygaspis quadrifrons with high-resolution X-ray computed tomography data. We report an osteological landmark (acetabulum) not previously detected in this taxon, the presence of which has repercussions that call for a reconsideration of the primary homology hypothesis for the identity of these bones in amphisbaenians and other squamates. Finally, we observed that the acetabulum and limb rudiments in amphisbaenians (i.e., the stylopodium when present) are situated medial to the pelvic girdle, contrasting with the large majority of tetrapods where these structures are laterally oriented.

  2. A new species of Leposternon Wagler, 1824 (Squamata, Amphisbaenia) from northeastern Argentina.

    PubMed

    Ribeiro, Siria; Santos-Jr, Alfredo P; Zaher, Hussam

    2015-10-29

    A new species of Leposternon is described from the Humid Chaco biome in Argentina. The species is known only from its type locality, at El Bagual Ecological Reserve, a conservation unit located in the province of Formosa. The new species can be distinguished from all its congeners by the presence of rostral processes in the maxillae and nasals that contact each other on the facial portion of the skull. Additionally, we present a key for the species of Leposternon.

  3. Karyological study of Amphisbaena ridleyi (Squamata, Amphisbaenidae), an endemic species of the Archipelago of Fernando de Noronha, Pernambuco, Brazil

    PubMed Central

    2010-01-01

    The karyotype of Amphisbaena ridleyi, an endemic species of the archipelago of Fernando de Noronha, in State of Pernambuco, Brazil, is described after conventional staining, Ag-NOR impregnation and fluorescence in situ hybridization (FISH) with a telomeric probe. The diploid number is 46, with nine pairs of macrochromosomes (three metacentrics, four subtelocentrics and two acrocentrics) and 14 pairs of microchromosomes. The Ag-NOR is located in the telomeric region of the long arm of metacentric chromosome 2 and FISH revealed signals only in the telomeric region of all chromosomes. Further cytogenetic data on other amphisbaenians as well as a robust phylogenetic hypothesis of this clade is needed in order to understand the evolutionary changes on amphisbaenian karyotypes. PMID:21637605

  4. Relict endemism of extant Rhineuridae (Amphisbaenia): testing for phylogenetic niche conservatism in the fossil record.

    PubMed

    Hipsley, Christy A; Müller, Johannes

    2014-03-01

    Rhineurid amphisbaenians are represented by a rich Cenozoic fossil record in North America, but today conisist of a single living species restricted to the Florida Peninsula. Such relict endemism may be the result of phylogenetic niche conservatism (PNC), the retention of ancestral traits preventing expansion into new environments. Most tests of PNC derive ancestral niche preferences from species' extant ecologies, while ignoring valuable paleontological information. To test if PNC contributes to the restricted distribution of modern Rhineura floridana, we compare the species' current environmental preferences (temperature, precipitation and soil) to paleoenvironmental data from the rhineurid fossil record. We find no evidence of PNC in modern R. floridana, as it also occurred in Florida during drier glacial periods. Ancient rhineurids also exhibit tolerance to changing climates, having undergone a shift from subtropical-humid to semi-arid savanna conditions during the Eocene-Oligocene transition. However, rhineurids nearly disappear from North America after the middle Miocene, potentially due to the onset of prolonged freezing temperatures following the mid-Miocene Climatic Optimum. This physiological limit of environmental tolerances could be interpreted as PNC for the entire family, but also characterizes much of Amphisbaenia, emphasizing the relevance of the temporal as well as phylogenetic scale at which PNC is investigated.

  5. Biogeography of worm lizards (Amphisbaenia) driven by end-Cretaceous mass extinction

    PubMed Central

    Longrich, Nicholas R.; Vinther, Jakob; Pyron, R. Alexander; Pisani, Davide; Gauthier, Jacques A.

    2015-01-01

    Worm lizards (Amphisbaenia) are burrowing squamates that live as subterranean predators. Their underground existence should limit dispersal, yet they are widespread throughout the Americas, Europe and Africa. This pattern was traditionally explained by continental drift, but molecular clocks suggest a Cenozoic diversification, long after the break-up of Pangaea, implying dispersal. Here, we describe primitive amphisbaenians from the North American Palaeocene, including the oldest known amphisbaenian, and provide new and older molecular divergence estimates for the clade, showing that worm lizards originated in North America, then radiated and dispersed in the Palaeogene following the Cretaceous-Palaeogene (K-Pg) extinction. This scenario implies at least three trans-oceanic dispersals: from North America to Europe, from North America to Africa and from Africa to South America. Amphisbaenians provide a striking case study in biogeography, suggesting that the role of continental drift in biogeography may be overstated. Instead, these patterns support Darwin and Wallace's hypothesis that the geographical ranges of modern clades result from dispersal, including oceanic rafting. Mass extinctions may facilitate dispersal events by eliminating competitors and predators that would otherwise hinder establishment of dispersing populations, removing biotic barriers to dispersal. PMID:25833855

  6. Biogeography of worm lizards (Amphisbaenia) driven by end-Cretaceous mass extinction.

    PubMed

    Longrich, Nicholas R; Vinther, Jakob; Pyron, R Alexander; Pisani, Davide; Gauthier, Jacques A

    2015-05-07

    Worm lizards (Amphisbaenia) are burrowing squamates that live as subterranean predators. Their underground existence should limit dispersal, yet they are widespread throughout the Americas, Europe and Africa. This pattern was traditionally explained by continental drift, but molecular clocks suggest a Cenozoic diversification, long after the break-up of Pangaea, implying dispersal. Here, we describe primitive amphisbaenians from the North American Palaeocene, including the oldest known amphisbaenian, and provide new and older molecular divergence estimates for the clade, showing that worm lizards originated in North America, then radiated and dispersed in the Palaeogene following the Cretaceous-Palaeogene (K-Pg) extinction. This scenario implies at least three trans-oceanic dispersals: from North America to Europe, from North America to Africa and from Africa to South America. Amphisbaenians provide a striking case study in biogeography, suggesting that the role of continental drift in biogeography may be overstated. Instead, these patterns support Darwin and Wallace's hypothesis that the geographical ranges of modern clades result from dispersal, including oceanic rafting. Mass extinctions may facilitate dispersal events by eliminating competitors and predators that would otherwise hinder establishment of dispersing populations, removing biotic barriers to dispersal.

  7. Genomic structure and expression of immunoglobulins in Squamata.

    PubMed

    Olivieri, David N; Garet, Elina; Estevez, Olivia; Sánchez-Espinel, Christian; Gambón-Deza, Francisco

    2016-04-01

    The Squamata order represents a major evolutionary reptile lineage, yet the structure and expression of immunoglobulins in this order has been scarcely studied in detail. From the genome sequences of four Squamata species (Gekko japonicus, Ophisaurus gracilis, Pogona vitticeps and Ophiophagus hannah) and RNA-seq datasets from 18 other Squamata species, we identified the immunoglobulins present in these animals as well as the tissues in which they are found. All Squamata have at least three immunoglobulin classes; namely, the immunoglobulins M, D, and Y. Unlike mammals, however, we provide evidence that some Squamata lineages possess more than one Cμ gene which is located downstream from the Cδ gene. The existence of two evolutionary lineages of immunoglobulin Y is shown. Additionally, it is demonstrated that while all Squamata species possess the λ light chain, only Iguanidae species possess the κ light chain.

  8. A new two-pored species of Amphisbaena (Squamata, Amphisbaenidae) from the Brazilian Cerrado, with a key to the two-pored species of Amphisbaena.

    PubMed

    Ribeiro, Síria; Gomes, Jerriane O; Silva, Helder Lúcio Rodrigues Da; Cintra, Carlos Eduardo D; Silva, Nelson Jorge Da Jr

    2016-08-03

    A new species of Amphisbaena is described from municipalities of Babaçulândia, State of Tocantins, and Estreito, State of Maranhão, northern Brazilian Cerrado. The new species differs from other two-pored species of the genus, by presenting mainly slender body shape; snout rounded in profile and dorsal view; high number of body annuli (328-342); 12-14 dorsal segments and 14-16 ventral in midbody half-annulus; autotomic site between 9-10th caudal annuli; absence of chevron-shaped anterior dorsal half-annuli; 20-23 caudal annuli; postmalar row absent; and precloacals pores arranged in a continuous series of the precloacal half-annuli. Additionally, we present a key for two-pored species of Amphisbaena.

  9. Morphological similarities between Amphisbaena mitchelli Procter, 1923 and A. miringoera Vanzolini, 1971 (Squamata: Amphisbaenidae): phylogenetic relatedness or morphological convergence?

    PubMed

    Almeida, João Paulo Felix Augusto De; Vechio, Francisco Dal; Teixeira, Mauro Jr; Rodrigues, Miguel Trefaut; Mott, Tamí

    2016-09-16

    To date, 22 species of amphisbaenids have been recorded at Brazilian Amazon (Ribeiro et al. 2008), six of them are small and have two pre-cloacal pores (Hoogmoed & Ávila-Pires 1991; Teixeira Jr. et al. 2014). Most of these species have narrow distributions, and its biology and phylogenetic relationships are poorly understood (Hoogmoed & Ávila-Pires 1991). Amphisbaena mitchelli Procter, 1923 and A. miringoera Vanzolini, 1971 share several morphological similarities that could reflect phylogenetic relatedness (Vanzolini 1971). Both have two pre-cloacal pores and a similar pattern of head scutelation, but whereas the first has 193-220 and 26-29 body and tail annuli, respectively, the latter has 250-264 and 22-24 (Vanzolini 1971).

  10. [Specific organization of ribosomal DNA arrays in Squamata].

    PubMed

    Voronov, A S; Shibalev, D V; Kupriianova, N S

    2008-11-01

    A first report on structural organization of ribosomal DNA arrays in some members of the order Squamata is presented. The data obtained point to unusually small (for vertebrates) size of the rDNA repetitive unit (approximately, 10 to 15 kb) in the lizard species examined. Analysis of BAC library of Uta stansburiana (Iguania) showed that haploid genome of this lizard contained a single cluster, consisting of about ten rDNA repeats. Determination of the extent of rDNA unit repetition in some other representatives of the order Squamata, using the method of comparative real-time PCR, showed that the number of rDNA units varied from one or several dozens in Iguanina to several hundred repeats in Scincomorpha and Varonoidea. The results are discussed in terms of an ambiguous position of the family Iguania on the evolutionary trees constructed based on morphological and molecular data.

  11. The complete mitochondrial genome of Eremias przewalskii (Squamata: Lacertidae).

    PubMed

    Du, Yu; Qiu, Qing-Bo; Tong, Qing-Lin; Lin, Long-Hui

    2016-05-01

    In this paper, the complete mitochondrial genome of Eremias przewalskii (Squamata: Lacertidae) is reported, which is a circular molecule of 18,225 bp in size. The base composition of mtDNA is as follows: 30.3% A, 27.9% T, 27.9% C and 13.9% G. The genome consists of 13 protein coding genes, 22 transfer RNAs, 2 ribosomal RNA genes and one putative control region.

  12. Habitat structural effect on squamata fauna of the restinga ecosystem in northeastern Brazil.

    PubMed

    Dias, Eduardo J R; Rocha, Carlos F D

    2014-03-01

    In this work, we surveyed data on richness and composition of squamatan reptiles and habitat structural effect in nine areas of restinga ecosystem in the State of Bahia, northeastern Brazil. The "restinga" ecosystems are coastal sand dune habitats on the coast of Brazil. Our main hypothesis is that the Squamata fauna composition along these restinga areas would be modulated by habitat structural. After 90 days of field sampling we recorded approximately 5% of reptile species known in Brazil. The composition of Squamata assemblages varied mainly based on the presence or absence of lizards of the genera Ameivula and Tropidurus. Our data showed that habitat structure consistently affected the composition of local Squamata fauna, especially lizards.

  13. The complete mitochondrial genome of Acanthosaura lepidogaster (Squamata: Agamidae).

    PubMed

    Yu, Xiu-Li; Du, Yu; Yao, Yun-Tao; Lin, Chi-Xian; Lin, Long-Hui

    2017-03-01

    In this paper, we report the complete mitochondrial genome of Acanthosaura lepidogaster (Squamata, Agamidae), which is a circular molecule of 16 899 bp in size and consists of 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs, and a control region. The overall base composition is as follows: T (22.8%), C (30.5%), A (32.3%), and G (14.4%). We constructed a phylogeny that included for 10 species of Leiolepidinae lizards and one outgroup Leiocephalus personatus constructed in BEAST, based on 15 mitochondrial genes (12S, 16S, ND1, ND2, COI, COII, ATP8, ATP6, COIII, ND3, ND4L, ND4, ND5, ND6, and cytochrome b). The topology of the phylogenetic tree is broadly similar to that mentioned by Pyron et al.

  14. A new species of Falcaustra (Nematoda: Kathlaniidae) in Nactus pelagicus (Squamata: Gekkonidae) from Tanna Island, Vanuatu.

    PubMed

    Bursey, Charles R; Goldberg, Stephen R; Hamilton, Alison M; Austin, Christopher C

    2010-10-01

    Falcaustra tannaensis n. sp. (Ascaridida: Kathlaniidae) from the large intestine of Nactus pelagicus (Squamata: Gekkonidae) is described and illustrated. Falcaustra tannaensis represents the first species from Oceanica to be assigned to the genus and is distinguished from other species of Falcaustra by the distribution pattern of caudal papillae (8 precloacal, 2 adcloacal, 10 postcloacal, and 1 median), length of spicules (2.43-2.68 mm), and presence of a pseudosucker.

  15. Development and characterization of 47 novel microsatellite markers for Vellozia squamata (Velloziaceae)1

    PubMed Central

    Duarte-Barbosa, Marcia; Bajay, Miklos M.; Zucchi, Maria I.; Pivello, Vânia R.

    2015-01-01

    • Premise of the study: We developed and validated microsatellite primers for Vellozia squamata (Velloziaceae), an endemic species of the cerrado (Brazilian savannas), to investigate the influence of different fire regimes on its genetic diversity and population structure. • Methods and Results: Using a selective hybridization method, we tested 51 SSR loci using a natural population of V. squamata and obtained 47 amplifiable loci. Among these, 26 loci were polymorphic and the average values of genetic diversity were: average number of alleles per locus (A¯) = 6.54, average number of alleles per polymorphic locus (A¯p) = 7.13, average observed heterozygosity (H¯o) = 0.22, average expected heterozygosity (H¯e) = 0.49, and average fixation index (F¯) = 0.55. • Conclusions: These 26 loci allowed us to assess the effects of distinct fire regimes on the genetic structure of V. squamata populations with the aim of establishing strategies for the conservation of this endemic species. The markers can also be useful for future pharmaceutical studies, as the species has great potential for medicinal and cosmetic applications. PMID:25699216

  16. Sclerotic Rings in Mosasaurs (Squamata: Mosasauridae): Structures and Taxonomic Diversity

    PubMed Central

    Yamashita, Momo; Konishi, Takuya; Sato, Tamaki

    2015-01-01

    Mosasaurs (Squamata: Mosasauridae) were a highly diverse, globally distributed group of aquatic lizards in the Late Cretaceous (98–66 million years ago) that exhibited a high degree of adaptation to life in water. To date, despite their rich fossil record, the anatomy of complete mosasaur sclerotic rings, embedded in the sclera of the eyeball, has not been thoroughly investigated. We here describe and compare sclerotic rings of four mosasaur genera, Tylosaurus, Platecarpus, Clidastes, and Mosasaurus, for the first time. Two specimens of Tylosaurus and Platecarpus share an exact scleral ossicle arrangement, excepting the missing portion in the specimen of Platecarpus. Furthermore, the exact arrangement and the total count of 14 ossicles per ring are shared between Tylosaurus and numerous living terrestrial lizard taxa, pertaining to both Iguania and Scleroglossa. In contrast, two species of Mosasaurus share the identical count of 12 ossicles and the arrangement with each other, while no living lizard taxa share exactly the same arrangement. Such a mosaic distribution of these traits both among squamates globally and among obligatorily aquatic mosasaurs specifically suggests that neither the ossicle count nor their arrangement played major roles in the aquatic adaptation in mosasaur eyes. All the mosasaur sclerotic rings examined consistently exhibit aperture eccentricity and the scleral ossicles with gently convex outer side. Hitherto unknown to any squamate taxa, one specimen of Platecarpus unexpectedly shows a raised, concentric band of roughened surface on the inner surface of the sclerotic ring. It is possible that one or both of these latter features may have related to adaptation towards aquatic vision in mosasaurs, but further quantitative study of extant reptilian clades containing both terrestrial and aquatic taxa is critical and necessary in order to understand possible adaptive significances of such osteological features. PMID:25692667

  17. Spermiogenesis in the imbricate alligator lizard, Barisia imbricata (Reptilia, Squamata, Anguidae).

    PubMed

    Gribbins, Kevin M; Rheubert, Justin L; Touzinsky, Katherine; Hanover, Jessica; Matchett, Caroline L; Granados-González, Gisela; Hernández-Gallegos, Oswaldo

    2013-06-01

    Although the events of spermiogenesis are commonly studied in amniotes, the amount of research available for Squamata is lacking. Many studies have described the morphological characteristics of mature spermatozoa in squamates, but few detail the ultrastructural changes that occur during spermiogenesis. This study's purpose is to gain a better understanding of the subcellular events of spermatid development within the Imbricate Alligator Lizard, Barisia imbricata. The morphological data presented here represent the first complete ultrastructural study of spermiogenesis within the family Anguidae. Samples of testes from four specimens collected on the northwest side of the Nevado de Toluca, México, were prepared using standard techniques for transmission electron microscopy. Many of the ultrastructural changes occurring during spermiogenesis within B. imbricata are similar to that of other squamates (i.e., early acrosome formation, chromatin condensation, flagella formation, annulus present, and a prominent manchette). However, there are a few unique characteristics within B. imbricata spermatids that to date have not been described during spermiogenesis in other squamates. For example, penetration of the acrosomal granule into the subacrosomal space to form the basal plate of the perforatorium during round spermatid development, the clover-shaped morphology of the developing nuclear fossa of the flagellum, and the bulbous shape to the perforatorium are all unique to the Imbricate Alligator Lizard. These anatomical character differences may be valuable nontraditional data that along with more traditional matrices (such as DNA sequences and gross morphological data) may help elucidate phylogenetic relationships, which are historically considered controversial within Squamata.

  18. Rate heterogeneity across Squamata, misleading ancestral state reconstruction and the importance of proper null model specification.

    PubMed

    Harrington, S; Reeder, T W

    2017-02-01

    The binary-state speciation and extinction (BiSSE) model has been used in many instances to identify state-dependent diversification and reconstruct ancestral states. However, recent studies have shown that the standard procedure of comparing the fit of the BiSSE model to constant-rate birth-death models often inappropriately favours the BiSSE model when diversification rates vary in a state-independent fashion. The newly developed HiSSE model enables researchers to identify state-dependent diversification rates while accounting for state-independent diversification at the same time. The HiSSE model also allows researchers to test state-dependent models against appropriate state-independent null models that have the same number of parameters as the state-dependent models being tested. We reanalyse two data sets that originally used BiSSE to reconstruct ancestral states within squamate reptiles and reached surprising conclusions regarding the evolution of toepads within Gekkota and viviparity across Squamata. We used this new method to demonstrate that there are many shifts in diversification rates across squamates. We then fit various HiSSE submodels and null models to the state and phylogenetic data and reconstructed states under these models. We found that there is no single, consistent signal for state-dependent diversification associated with toepads in gekkotans or viviparity across all squamates. Our reconstructions show limited support for the recently proposed hypotheses that toepads evolved multiple times independently in Gekkota and that transitions from viviparity to oviparity are common in Squamata. Our results highlight the importance of considering an adequate pool of models and null models when estimating diversification rate parameters and reconstructing ancestral states.

  19. Plasma lipid concentrations for some Brazilian lizards.

    PubMed

    Gillett, M P; Lima, V L; Costa, J C; Sibrian, A M

    1979-01-01

    1. Plasma concentrations of cholesterol, cholesteryl esters, phospholipids and triglycerides were determined for ten species of Brazilian lizards, Iguana iguana, Tropidurus torquatos and T. semitaeniatus (Iguanidae), Tupinambis teguixin, Ameiva ameiva and Cnemidophorus ocellifer (Teiidae), Mabuya maculata (Scincidae), Hemidactylus mabouia (Gekkonidae), Amphisbaenia vermicularis and Leposternon polystegum (Amphisbaenidae). 2. Considerable inter- and intra-species variations in plasma lipid concentrations were observed. 3. The percentage of total cholesterol esterified and the individual phospholipid composition of plasma were relatively constant for each species. 4. Over 60% of the cholesteryl esters present in plasma from three species each of iguanid and teiid lizards were polyenoic.

  20. Female heterogamety in Madagascar chameleons (Squamata: Chamaeleonidae: Furcifer): differentiation of sex and neo-sex chromosomes.

    PubMed

    Rovatsos, Michail; Johnson Pokorná, Martina; Altmanová, Marie; Kratochvíl, Lukáš

    2015-08-19

    Amniotes possess variability in sex determining mechanisms, however, this diversity is still only partially known throughout the clade and sex determining systems still remain unknown even in such a popular and distinctive lineage as chameleons (Squamata: Acrodonta: Chamaeleonidae). Here, we present evidence for female heterogamety in this group. The Malagasy giant chameleon (Furcifer oustaleti) (chromosome number 2n = 22) possesses heteromorphic Z and W sex chromosomes with heterochromatic W. The panther chameleon (Furcifer pardalis) (2n = 22 in males, 21 in females), the second most popular chameleon species in the world pet trade, exhibits a rather rare Z1Z1Z2Z2/Z1Z2W system of multiple sex chromosomes, which most likely evolved from W-autosome fusion. Notably, its neo-W chromosome is partially heterochromatic and its female-specific genetic content has expanded into the previously autosomal region. Showing clear evidence for genotypic sex determination in the panther chameleon, we resolve the long-standing question of whether or not environmental sex determination exists in this species. Together with recent findings in other reptile lineages, our work demonstrates that female heterogamety is widespread among amniotes, adding another important piece to the mosaic of knowledge on sex determination in amniotes needed to understand the evolution of this important trait.

  1. A reevaluation of the unusual abdominal musculature of squamate reptiles (Reptilia: Squamata).

    PubMed

    Bhullar, Bhart-Anjan S

    2009-08-01

    The abdominal muscles of lizards and snakes (Squamata) have been the subject of periodic attention from anatomists, embryologists, and systematists. Until now, the presence of a superficial portion of the m. rectus abdominis, named the m. rectus abdominis lateralis, has been considered a key synapomorphy of the clade Autarchoglossa, which includes all extant squamates save Gekkota and Iguania. However, the precise anatomical relations of the m. rectus abdominis lateralis have never been fully investigated. Here, I show that the m. rectus abdominis lateralis is present in Iguania. Its absence in Gekkota represents rare gross anatomical support for recent molecular-structure-based hypotheses of squamate relationships placing geckoes as sister to the remaining squamates. Where present, it is the most superficial trunk muscle, exterior to the m. obliquus externus. The separation of the m. rectus abdominis lateralis from the m. rectus abdominis occurs as the m. obliquus externus aponeurosis and part of the m. obliquus internus aponeurosis emerge superficially to form the outer portion of the rectus sheath. In Autarchoglossa, the contralateral mm. recti abdomines laterales meet at the midline and are attached to the imbricae of the transverse scale rows characteristic of the clade, suggesting developmental, functional, and evolutionary association. Because the m. rectus abdominis lateralis is sometimes continuous with the pectoralis, its exclusive association with the m. rectus abdominis is questionable. It may be a neomorphic layer that is part of the abaxial developmental system, comprising those muscles whose connective tissue is largely derived from lateral plate as opposed to somatic mesoderm.

  2. Female heterogamety in Madagascar chameleons (Squamata: Chamaeleonidae: Furcifer): differentiation of sex and neo-sex chromosomes

    PubMed Central

    Rovatsos, Michail; Pokorná, Martina Johnson; Altmanová, Marie; Kratochvíl, Lukáš

    2015-01-01

    Amniotes possess variability in sex determining mechanisms, however, this diversity is still only partially known throughout the clade and sex determining systems still remain unknown even in such a popular and distinctive lineage as chameleons (Squamata: Acrodonta: Chamaeleonidae). Here, we present evidence for female heterogamety in this group. The Malagasy giant chameleon (Furcifer oustaleti) (chromosome number 2n = 22) possesses heteromorphic Z and W sex chromosomes with heterochromatic W. The panther chameleon (Furcifer pardalis) (2n = 22 in males, 21 in females), the second most popular chameleon species in the world pet trade, exhibits a rather rare Z1Z1Z2Z2/Z1Z2W system of multiple sex chromosomes, which most likely evolved from W-autosome fusion. Notably, its neo-W chromosome is partially heterochromatic and its female-specific genetic content has expanded into the previously autosomal region. Showing clear evidence for genotypic sex determination in the panther chameleon, we resolve the long-standing question of whether or not environmental sex determination exists in this species. Together with recent findings in other reptile lineages, our work demonstrates that female heterogamety is widespread among amniotes, adding another important piece to the mosaic of knowledge on sex determination in amniotes needed to understand the evolution of this important trait. PMID:26286647

  3. Molecular phylogenetic and dating analyses using mitochondrial DNA sequences of eyelid geckos (Squamata: Eublepharidae).

    PubMed

    Jonniaux, Pierre; Kumazawa, Yoshinori

    2008-01-15

    Mitochondrial DNA sequences of approximately 2.3 kbp including the complete NADH dehydrogenase subunit 2 gene and its flanking genes, as well as parts of 12S and 16S rRNA genes were determined from major species of the eyelid gecko family Eublepharidae sensu [Kluge, A.G. 1987. Cladistic relationships in the Gekkonoidea (Squamata, Sauria). Misc. Publ. Mus. Zool. Univ. Michigan 173, 1-54.]. In contrast to previous morphological studies, phylogenetic analyses based on these sequences supported that Eublepharidae and Gekkonidae form a sister group with Pygopodidae, raising the possibility of homoplasious character change in some key features of geckos, such as reduction of movable eyelids and innovation of climbing toe pads. The phylogenetic analyses also provided a well-resolved tree for relationships between the eublepharid species. The Bayesian estimation of divergence times without assuming the molecular clock suggested the Jurassic divergence of Eublepharidae from Gekkonidae and radiations of most eublepharid genera around the Cretaceous. These dating results appeared to be robust against some conditional changes for time estimation, such as gene regions used, taxon representation, and data partitioning. Taken together with geological evidence, these results support the vicariant divergence of Eublepharidae and Gekkonidae by the breakup of Pangea into Laurasia and Gondwanaland, and recent dispersal of two African eublepharid genera from Eurasia to Africa after these landmasses were connected in the Early Miocene.

  4. Type specimens of Crotalus scutulatus (Chordata: Reptilia: Squamata: Viperidae) re-examined, with new evidence after more than a century of confusion

    USGS Publications Warehouse

    Cardwell, Michael D.; Gotte, Steve W.; McDiarmid, Roy W.; Gilmore, Ned; Poindexter, James A.

    2013-01-01

    The original description of Crotalus scutulatus (Chordata: Reptilia: Squamata: Viperidae) was published in 1861 by Robert Kennicott, who did not identify a type specimen or a type locality. We review the history of specimens purported to be the type(s) and various designations of type locality. We provide evidence that ANSP 7069 (formerly one of two specimens of USNM 5027) is the holotype and that the appropriate type locality is Fort Buchanan, near present-day Sonoita, in Santa Cruz County, Arizona.

  5. Atypical reproductive cycles in a population of Sceloporus grammicus (Squamata: Phrynosomatidae) from the Mexican Plateau

    PubMed Central

    Ramírez-Bautista, Aurelio; Stephenson, Barry P; Lozano, Abraham; Uribe-Rodríguez, Héctor; Leyte Manrique, Adrian

    2012-01-01

    The spiny lizard Sceloporus grammicus (Squamata: Phrynosomatidae) is a small reptile from central México and the southern United States, occurring in a wide geographic area characterized by extensive variation in topographic and climatic regimes. Genetic variation among lineages from central México is substantial, though the extent to which this variation corresponds with life-history traits remains obscure. To address part of this puzzle, we studied a population of S. grammicus from Tepeapulco, Hidalgo, México. Male-biased sexual dimorphism was extensive in this population; males were larger than females overall, and expressed proportionately larger heads and longer limbs. Minimum size at sexual maturity was similar in the sexes (males: 43 mm; females: 42 mm). In contrast to other populations from the Central Plateau, reproductive activity of males and females was synchronous. Testicular recrudescence of adult males was initiated in October–November, and maximum testis size maintained from December to July. Female reproductive activity showed no clear seasonal pattern: females had vitellogenic follicles from October to July, and pregnant females were found throughout the year. Female body size was not related to litter size. Neither male nor female gonadal mass was correlated with any abiotic environmental variable examined. Differences in reproductive characteristics among populations of S. grammicus might be indicative of plasticity in response to local environmental conditions, local adaptation, or complex gene × environment interactions. We consider these results in the context of previously studied populations of S. grammicus from the Central Plateau and elsewhere, and propose directions for future research. PMID:22957191

  6. Cytochemical study of spermiogenesis and mature spermatozoa in the lizard Tropidurus itambere (Reptilia, Squamata).

    PubMed

    Ferreira, Adelina; Dolder, Heidi

    2003-01-01

    The present study was undertaken to detect essential components of spermatozoa by ultrastructural and cytochemical analyses of testis and epididymis of the lizard Tropidurus itambere at different points of its annual reproductive cycle. Cytochemical investigations of spermiogenesis have not been performed so far in Squamata and are scarce for lower vertebrates. Essential components are: 1) polysaccharides, identified by PAS staining, abundantly present in Sertoli cell elongations, acrosomal vesicles and the acrosome of sperm cells; 2) glycoconjugate variations, labeled by different lectins and used to investigate cell modifications during spermiogenesis and found in mature spermatozoa in the female's seminal receptacle; 3) basic proteins, present in large quantities in spermatozoa in the subacrosomal cone, the pericentriolar material, the midpiece dense bodies, the peripheral fibers of the axoneme, and the fibrous sheath of the flagellum; 4) the final reaction product of acid phosphatase activity in several stages of acrosome development, specifically in the clear zone and epinuclear electron-lucent region of spermatozoal acrosomes, as well as in very active lysosomes found during the quiescent period of the reproductive cycle; 5) lipids, abundantly present in the cytoplasm of Leydig cells during the quiescent period. The cytochemical methods show that the ultrastructurally complex acrosome is also biochemically heterogeneous, with specific layers rich in glycoproteins, basic proteins or acid phosphatase. These different components may play a role during sperm penetration into the ovule. Basic proteins are largely responsible for structures surrounding the axoneme to provide resistance to the flagellum. In the quiescent period, acid phosphatase activity is involved in the elimination of superfluous sperm cells, whereas lipids in Leydig cells are used for hormone synthesis which starts at this time point to initiate a new reproductive cycle. Variations in lectin

  7. A phylogeny and revised classification of Squamata, including 4161 species of lizards and snakes

    PubMed Central

    2013-01-01

    Background The extant squamates (>9400 known species of lizards and snakes) are one of the most diverse and conspicuous radiations of terrestrial vertebrates, but no studies have attempted to reconstruct a phylogeny for the group with large-scale taxon sampling. Such an estimate is invaluable for comparative evolutionary studies, and to address their classification. Here, we present the first large-scale phylogenetic estimate for Squamata. Results The estimated phylogeny contains 4161 species, representing all currently recognized families and subfamilies. The analysis is based on up to 12896 base pairs of sequence data per species (average = 2497 bp) from 12 genes, including seven nuclear loci (BDNF, c-mos, NT3, PDC, R35, RAG-1, and RAG-2), and five mitochondrial genes (12S, 16S, cytochrome b, ND2, and ND4). The tree provides important confirmation for recent estimates of higher-level squamate phylogeny based on molecular data (but with more limited taxon sampling), estimates that are very different from previous morphology-based hypotheses. The tree also includes many relationships that differ from previous molecular estimates and many that differ from traditional taxonomy. Conclusions We present a new large-scale phylogeny of squamate reptiles that should be a valuable resource for future comparative studies. We also present a revised classification of squamates at the family and subfamily level to bring the taxonomy more in line with the new phylogenetic hypothesis. This classification includes new, resurrected, and modified subfamilies within gymnophthalmid and scincid lizards, and boid, colubrid, and lamprophiid snakes. PMID:23627680

  8. Liolaemus lizards (Squamata: Liolaemidae) as hosts for the nymph of Amblyomma parvitarsum (Acari: Ixodidae), with notes on Rickettsia infection.

    PubMed

    Muñoz-Leal, Sebastián; Tarragona, Evelina L; Martins, Thiago F; Martín, Claudia M; Burgos-Gallardo, Freddy; Nava, Santiago; Labruna, Marcelo B; González-Acuña, Daniel

    2016-10-01

    Adults of Amblyomma parvitarsum are common ectoparasites of South American camelids of the genera Lama and Vicugna, occuring in highlands of Argentina, Bolivia, Chile, Peru and also in Argentinean Patagonia. Whereas larval stages of this tick are known to feed on small lizards, host records for the nymphal instar have remained unreported. Supported by morphological and molecular analyses, herein we report A. parvitarsum nymphs parasitizing two Liolaemus species (Reptilia: Squamata) in the Andean Plateau of Argentina and Chile. Additionally, by a PCR screening targetting gltA and ompA genes, DNA of Rickettsia was detected in one of the collected nymphs. Obtained sequences of this agent were identical to a recent Rickettsia sp. described infecting adults of this tick species in Chile and Argentina.

  9. Record length, mass, and clutch size in the nonindigenous Burmese Python, Python bivittatus Kuhl 1820 (Squamata: Pythonidae), in Florida

    USGS Publications Warehouse

    Krysko, Kenneth L.; Hart, Kristen M.; Smith, Brian J.; Selby, Thomas H.; Cherkiss, Michael S.; Coutu, Nicholas T.; Reichart, Rebecca M.; Nuñez, Leroy P.; Mazzotti, Frank J.; Snow, Ray W.

    2012-01-01

    The Burmese Python, Python bivittatus Kuhl 1820 (Squamata: Pythonidae), is indigenous to northern India,east to southern China, and south to Vietnam and a few islands in Indonesia (Barker and Barker 2008, Reed and Rodda 2009). This species has been introduced since at least 1979 in southern Florida, USA, where it likely began reproducing and became established during the 1980s (Meshaka et al. 2000, Snowet al. 2007b,Kraus 2009, Krysko et al. 2011, Willson et al. 2011). Python bivittatus has been documented in Florida consuming a variety of mammals and birds, and the American Alligator(Alligator mississippiensis) (Snowet al. 2007a, 2007b; Harvey et al. 2008; Rochford et al. 2010b; Holbrook and Chesnes 2011), many of which are protected species. Herein, we provide details on two of the largest known wild P. bivittatus in Florida to date, including current records on length,mass,clutch size, and diet.

  10. A new species of Hepatozoon Miller, 1908 (Apicomplexa: Adelerina) from the snake Philodryas nattereri Steindachner (Squamata: Dipsadidae) in northeastern Brazil.

    PubMed

    Borges-Nojosa, Diva M; Borges-Leite, M Juliana; Maia, João P; Zanchi-Silva, Djan; da Rocha Braga, Roberta; Harris, D James

    2017-01-01

    Based on both unique morphological characteristics of the gamont, distinct changes caused to the host erythrocyte and analysis of partial 18S rRNA gene sequences, a new parasite of the genus Hepatozoon Miller, 1908 is described from the snake Philodryas nattereri Steindachner (Squamata: Dipsadidae) in northeastern Brazil. The new species, Hepatozoon musa n. sp., is characterized by large and curved mature gamonts (18.9 ± 0.9 μm in length and 3.8 ± 0.3 μm in width) that considerably engorge infected host erythrocytes and displace the nucleus laterally, which become longer and thinner. Phylogenetic estimates indicate the new species is more closely related to the recently described Hepatozoon cuestensis O'Dwyer, Moço, Paduan, Spenassatto, Silva & Ribolla, 2013, from Brazilian rattlesnakes. These recent findings highlight the need for further studies of Hepatozoon to better determine the biodiversity of this common but poorly-studied parasite group.

  11. Autocrine and paracrine Shh signaling are necessary for tooth morphogenesis, but not tooth replacement in snakes and lizards (Squamata).

    PubMed

    Handrigan, Gregory R; Richman, Joy M

    2010-01-01

    Here we study the role of Shh signaling in tooth morphogenesis and successional tooth initiation in snakes and lizards (Squamata). By characterizing the expression of Shh pathway receptor Ptc1 in the developing dentitions of three species (Eublepharis macularius, Python regius, and Pogona vitticeps) and by performing gain- and loss-of-function experiments, we demonstrate that Shh signaling is active in the squamate tooth bud and is required for its normal morphogenesis. Shh apparently mediates tooth morphogenesis by separate paracrine- and autocrine-mediated functions. According to this model, paracrine Shh signaling induces cell proliferation in the cervical loop, outer enamel epithelium, and dental papilla. Autocrine signaling within the stellate reticulum instead appears to regulate cell survival. By treating squamate dental explants with Hh antagonist cyclopamine, we induced tooth phenotypes that closely resemble the morphological and differentiation defects of vestigial, first-generation teeth in the bearded dragon P. vitticeps. Our finding that these vestigial teeth are deficient in epithelial Shh signaling further corroborates that Shh is needed for the normal development of teeth in snakes and lizards. Finally, in this study, we definitively refute a role for Shh signaling in successional dental lamina formation and conclude that other pathways regulate tooth replacement in squamates.

  12. Nomenclature of Vertebral Laminae in Lizards, with Comments on Ontogenetic and Serial Variation in Lacertini (Squamata, Lacertidae)

    PubMed Central

    Tschopp, Emanuel

    2016-01-01

    Vertebral laminae are bony ridges or sheets that connect important morphological landmarks on the vertebrae, like diapophyses or zygapophyses. They usually exhibit some serial variation throughout the column. A consistent terminology facilitates the morphological description of this variation, and the recognition of patterns that could be taxonomically significant and could serve as phylogenetic characters. Such a terminology was designed for saurischian dinosaurs, and has also been applied to other members of Archosauriformes. Herein, this terminology is applied for the first time to lizards (Squamata). Probably due to their generally smaller size compared to saurischian dinosaurs, lizards have less developed vertebral laminae. Some laminae could not be recognized in this group and others require new names to account for differences in basic vertebral morphology. For instance, the fusion of diapophysis and parapophysis in lacertids into a structure called synapophysis necessitates the creation of the new term synapophyseal laminae for both diapophyseal and parapophyseal laminae. An assessment of occurrence and serial variation in a number of lacertid species shows that some laminae develop throughout ontogeny or only occur in large-sized species, whereas the distribution of other laminae might prove to be taxonomically significant in future. PMID:26907769

  13. Nomenclature of Vertebral Laminae in Lizards, with Comments on Ontogenetic and Serial Variation in Lacertini (Squamata, Lacertidae).

    PubMed

    Tschopp, Emanuel

    2016-01-01

    Vertebral laminae are bony ridges or sheets that connect important morphological landmarks on the vertebrae, like diapophyses or zygapophyses. They usually exhibit some serial variation throughout the column. A consistent terminology facilitates the morphological description of this variation, and the recognition of patterns that could be taxonomically significant and could serve as phylogenetic characters. Such a terminology was designed for saurischian dinosaurs, and has also been applied to other members of Archosauriformes. Herein, this terminology is applied for the first time to lizards (Squamata). Probably due to their generally smaller size compared to saurischian dinosaurs, lizards have less developed vertebral laminae. Some laminae could not be recognized in this group and others require new names to account for differences in basic vertebral morphology. For instance, the fusion of diapophysis and parapophysis in lacertids into a structure called synapophysis necessitates the creation of the new term synapophyseal laminae for both diapophyseal and parapophyseal laminae. An assessment of occurrence and serial variation in a number of lacertid species shows that some laminae develop throughout ontogeny or only occur in large-sized species, whereas the distribution of other laminae might prove to be taxonomically significant in future.

  14. Static osteogenesis does not precede dynamic osteogenesis in periosteal ossification of Pleurodeles (Caudata, Amphibia) and Pogona (Squamata, Lepidosauria).

    PubMed

    Cubo, Jorge; Hui, Mylaine; Clarac, François; Quilhac, Alexandra

    2017-02-01

    Two successive mechanisms have been described in perichondral ossification: (1) in static osteogenesis, mesenchymal cells differentiate into stationary osteoblasts oriented randomly, which differentiate into osteocytes in the same site; (2) in dynamic osteogenesis, mesenchymal cells differentiate into osteoblasts that are all oriented in the same direction and move back as they secrete collagen fibers. This study is aimed at testing the hypothesis that the ontogenetic sequence static then dynamic osteogenesis observed in the chicken and in the rabbit is homologous and was acquired by the last common ancestor of amniotes or at a more inclusive node. For this we analyze the developmental patterns of Pleurodeles (Caudata, Amphibia) and those of the lizard Pogona (Squamata, Lepidosauria). We processed Pleurodeles larvae and Pogona embryos, prepared thin and ultrathin sections of appendicular bones, and analyzed them using light and transmission electron microscopy. We show that static osteogenesis does not precede dynamic osteogenesis in periosteal ossification of Pleurodeles and Pogona. Therefore, the null hypothesis is rejected and according to the parsimony method the ontogenetic sequence observed in the chicken and in the rabbit are convergent. In Pleurodeles and Pogona dynamic osteogenesis occur without a previous rigid mineralized framework, whereas in the chicken and in the rabbit dynamic osteogenesis seems to take place over a mineralized support whether bone (in perichondral ossification) or calcified cartilage (in endochondral ossification). Interestingly, in typical dynamic osteogenesis, osteoblasts show an axis (basal nucleus-distal endoplasmic reticulum) perpendicular to the front of secreted unmineralized bone matrix, whereas in Pleurodeles and Pogona this axis is parallel to the bone matrix.

  15. The ultrastructure of the spermatozoon of the lizard Iguana iguana (Reptilia, Squamata, Iguanidae) and the variability of sperm morphology among iguanian lizards

    PubMed Central

    Vieira, Gustavo H C; Colli, Guarino R; Báo, Sônia N

    2004-01-01

    The spermatozoon of Iguana iguana is filiform and resembles that of other iguanian lizards, being most similar to Tropidurus. All sperm synapomorphies of Tetrapoda, Amniota and Squamata are present in the sperm of Iguana iguana. By reconstructing the evolution of 30 sperm characters we identified a novel synapomorphy of Iguania: the presence of a well-developed acrosomal ridge at the level of the epinuclear lucent zone. Because of the poor topological resolution among iguanian clades we could not discount the possibility of convergence or neutral selection as determinant of the variability in characteristics of the sperm cell. In agreement with previous studies, we identified heterogeneous rates of evolution among the three main regions of the sperm cell, namely the head, midpiece and tail. PMID:15198687

  16. The ultrastructure of the spermatozoon of the lizard Iguana iguana (Reptilia, Squamata, Iguanidae) and the variability of sperm morphology among iguanian lizards.

    PubMed

    Vieira, Gustavo H C; Colli, Guarino R; Báo, Sônia N

    2004-06-01

    The spermatozoon of Iguana iguana is filiform and resembles that of other iguanian lizards, being most similar to Tropidurus. All sperm synapomorphies of Tetrapoda, Amniota and Squamata are present in the sperm of Iguana iguana. By reconstructing the evolution of 30 sperm characters we identified a novel synapomorphy of Iguania: the presence of a well-developed acrosomal ridge at the level of the epinuclear lucent zone. Because of the poor topological resolution among iguanian clades we could not discount the possibility of convergence or neutral selection as determinant of the variability in characteristics of the sperm cell. In agreement with previous studies, we identified heterogeneous rates of evolution among the three main regions of the sperm cell, namely the head, midpiece and tail.

  17. Physaloptera bainae n. sp. (Nematoda: Physalopteridae) parasitic in Salvator merianae (Squamata: Teiidae), with a key to Physaloptera species parasitizing reptiles from Brazil.

    PubMed

    Pereira, Felipe B; Alves, Philippe V; Rocha, Bárbara M; de Souza Lima, Sueli; Luque, José L

    2014-04-01

    Physaloptera bainae n. sp. (Nematoda: Physalopteridae) from stomach of the large "tegú" lizard Salvator merianae (Squamata: Teiidae), collected in an ecological park that is part of the Atlantic Rainforest biome in Juiz de Fora, Minas Gerais, Brazil, is described. The new species which has females with didelphic uterus, is the only species of the genus exhibiting external teeth in the form of 4 spines that are organized in a cross-shaped pattern at the anterior apical end, with 2 minute adcloacal papillae on the anterior part of cloacal aperture in males and a large cuticular expansion at the anterior end of females. Moreover, P. bainae n. sp. can be differentiated from the other congeners by the combination of other features, e.g., number (23) and pattern of caudal papillae, spicule size (left 554-600; right 589-617) and vulval position (on the first third of body), and because the specimens are particularly large and robust. Physaloptera monodens is considered a junior synonym of P. obtusissima. In addition, a key to Physaloptera species parasitizing reptiles from Brazil is provided.

  18. Understanding the life of a sandy beach polychaete of functional importance - Scolelepis squamata (Polychaeta: Spionidae) on Belgian sandy beaches (northeastern Atlantic, North Sea)

    NASA Astrophysics Data System (ADS)

    Speybroeck, Jeroen; Alsteens, Lotte; Vincx, Magda; Degraer, Steven

    2007-08-01

    The cosmopolitan sandy beach polychaete Scolelepis squamata constitutes an important food resource for juvenile flatfish and wading birds in the northeastern Atlantic, thus playing an important role in sandy beach ecosystem functioning. However, its population dynamics and life history in this part of the world have gone widely uninvestigated. Eight beach transects on Belgian sandy beaches were sampled monthly from October 2003 until October 2004, in order to investigate seasonal trends in the species' abundance, biomass, secondary production, and patterns in reproduction and zonation. Average density, modal density and modal biomass (ash-free dry weight) (mean average density = 169 ± 9 SE ind/m 2; mean modal density = 505 ± 38 SE ind/m 2; mean modal biomass = 0.25 ± 0.02 SE g/m 2) did not exhibit major seasonal changes, whereas average biomass (0.081 ± 0.005 SE g/m 2) and individuals and biomass per strip transect (IST = 16286 ± 1330 SE ind/m; BMST = 7.8 + 0.7 SE g/m) did, peaking in May 2004. Production was calculated at 1.9 g/(m 2*year) (size-frequency method, SFM) and 0.88 g/(m 2*year) (mass specific growth rate method, MSGR) and mean annual biomass was 0.797 g/m 2; resulting in a P/B ratio of 2.40/year (SFM) and 1.11/year (MSGR), which is intermediate to moderately low compared to other polychaete species. Gravid individuals were found from February until August and a single recruitment period was observed from July until September. An average sex ratio of 1.41 ± 0.08 SE was calculated, with a female predominance. Highest densities (>200 ind/m 2) were mostly found above 3 m above MLLWS and at a median grain size from 190 to 320 μm. Average modal or peak density along each transect was situated from 3.95 m up to 4.40 m above MLLWS, in contrast to some other studies where the species was restricted to mid-tidal levels. Significant differences in elevation of peak density were found between non-gravid (411 ± 4 SE cm) and gravid (402 ± 5 SE cm) animals

  19. Phylogenetic relationships among amphisbaenian reptiles based on complete mitochondrial genomic sequences

    SciTech Connect

    Macey, J. Robert; Papenfuss, Theodore J.; Kuehl, Jennifer V.; Fourcade, H. Matthew; Boore, Jeffrey L.

    2004-05-19

    Complete mitochondrial genomic sequences are reported from 12 members in the four families of the reptile group Amphisbaenia. Analysis of 11,946 aligned nucleotide positions (5,797 informative) produces a robust phylogenetic hypothesis. The family Rhineuridae is basal and Bipedidae is the sister taxon to the Amphisbaenidae plus Trogonophidae. Amphisbaenian reptiles are surprisingly old, predating the breakup of Pangaea 200 million years before present, because successive basal taxa (Rhineuridae and Bipedidae) are situated in tectonic regions of Laurasia and nested taxa (Amphisbaenidae and Trogonophidae) are found in Gondwanan regions. Thorough sampling within the Bipedidae shows that it is not tectonic movement of Baja California away from the Mexican mainland that is primary in isolating Bipes species, but rather that primary vicariance occurred between northern and southern groups. Amphisbaenian families show parallel reduction in number of limbs and Bipes species exhibit parallel reduction in number of digits. A measure is developed for comparing the phylogenetic information content of various genes. A synapomorphic trait defining the Bipedidae is a shift from the typical vertebrate mitochondrial gene arrangement to the derived state of trnE and nad6. In addition, a tandem duplication of trnT and trnP is observed in B. biporus with a pattern of pseudogene formation that varies among populations. The first case of convergent rearrangement of the mitochondrial genome among animals demonstrated by complete genomic sequences is reported. Relative to most vertebrates, the Rhineuridae has the block nad6, trnE switched in order with cob, trnT, trnP, as they are in birds.

  20. On the taxonomic status of the European Scolelepis (Scolelepis) squamata

    (Polychaeta: Spionidae), with description of a new species from southern Europe

    .

    PubMed

    Surugiu, Victor

    2016-09-05

    In order to clarify taxonomic problems relating to the identity of Scolelepis (Scolelepis) specimens from the Black Sea, the identified material was compared with specimens of Scolelepis cirratulus (Delle Chiaje, 1829) from the Mediterranean, of S. squamata (Abildgaard, in O.F. Müller, 1806) from the North Sea and the Atlantic coast of Spain, and with the syntypes of S. mesnili (Bellan & Lagardère, 1971) from the Atlantic coast of France. The examination of a large number of specimens (both juveniles and adults) reveals that the currently accepted morphological differences distinguishing all species show size-related patterns, suggesting that they all belong to one species. Therefore, this study supports the view that Scolelepis cirratulus and Scolelepis mesnili are junior synonyms of Scolelepis (Scolelepis) squamata. As a result of the re-assessment of the species limits of Scolelepis (Scolelepis) squamata, a new species, Scolelepis (Scolelepis) neglecta sp. nov., is distinguished and described from the Cantabrian coast of Spain. It inhabits shallow sublittoral fine sands and was earlier misidentified and reported from the Atlantic coast of Europe and the Mediterranean Sea as Scolelepis squamata, Scolelepis mesnili, Scolelepis cantabra (Rioja, 1918), or Dispio uncinata Hartman, 1951. The new species is characterized by having a trilobate prostomium with an acuminate medial portion, a short peristomium with well-developed dorso-lateral wings, short palps with two longitudinal bands of elevated lobes, neuropodial postchaetal lamellae notched from chaetigers 14-41, and strongly curved bidentate neuropodial hooded hooks with a slight constriction on the shaft starting from chaetigers 19-49. The morphology, diagnostic characters and ecology of both Scolelepis (Scolelepis) squamata and Scolelepis (Scolelepis) neglecta sp. nov. are discussed.

  1. Phylogeny of Neotropical Cercosaura (Squamata: Gymnophthalmidae) lizards.

    PubMed

    Torres-Carvajal, Omar; Lobos, Simón E; Venegas, Pablo J

    2015-12-01

    Among Neotropical lizards, the geographically widespread gymnophthalmid Cercosaura as currently defined includes lowland and highland taxa from Panama to Argentina, with some species occurring in the northern Andes. In this study we analyze three mitochondrial (12S, 16S, ND4) and one nuclear (c-mos) gene using Bayesian methods to clarify the phylogenetic relationships among most species of Cercosaura based on a well-supported phylogenetic hypothesis that also includes a large sample of other taxa within Cercosaurini. The phylogenetic tree obtained in this paper shows that Cercosaura as currently defined is not monophyletic. Two species from the northern Andes (C. dicra and C. vertebralis) are nested within Pholidobolus, which has been formerly recognized as a major radiation along the Andes of Ecuador and Colombia. Therefore, Cercosaura has probably not diversified in the northern Andes, although the phylogenetic position of C. hypnoides from the Andes of Colombia remains unknown. Tree topology and genetic distances support both recognition of C. ocellata bassleri as a distinct species, C. bassleri, and recognition of C. argula and C. oshaughnessyi as two different species. In the interest of promoting clarity and precision regarding the names of clades of gymnophthalmid lizards, we propose a phylogenetic definition of Cercosaura.

  2. Cytogenetic studies on Gonatodes (Reptilia, Squamata, Sphaerodactylidae).

    PubMed

    Schmid, Michael; Steinlein, Claus; Feichtinger, Wolfgang; Haaf, Thomas; Mijares-Urrutia, Abraham; Schargel, Walter E; Hedges, S Blair

    2014-01-01

    Mitotic and meiotic chromosomes of 5 species of the reptile genus Gonatodes are described by means of conventional staining, banding analyses and in situ hybridization using a synthetic telomeric DNA probe. The amount, location and fluorochrome affinities of constitutive heterochromatin, the number and positions of nucleolus organizer regions, and the patterns of telomeric DNA sequences were determined for most of the species. The karyotypes of G. falconensis and G. taniae from northern Venezuela are distinguished by their extraordinarily reduced diploid chromosome number of 2n = 16, which is the lowest value found so far in reptiles. In contrast to most other reptiles, both species have exclusively large biarmed (meta- and submetacentric) chromosomes. Comparison of the karyotypes of G. falconensis and G. taniae with those of other Gonatodes species indicates that the exceptional 2n = 16 karyotype originated by a series of 8 centric fusions. The karyotypes of G. falconensis and G. taniae are further characterized by the presence of considerable amounts of (TTAGGG)n telomeric sequences in the centromeric regions of all chromosomes. These are probably not only relics of the centric fusion events, but a component of the highly repetitive DNA in the constitutive heterochromatin of the chromosomes. The genome sizes of 4 Gonatodes species were determined using flow cytometry. For comparative purposes, all previously published cytogenetic data on Gonatodes and other sphaerodactylids are included and discussed.

  3. Random Sampling of Squamate Reptiles in Spanish Natural Reserves Reveals the Presence of Novel Adenoviruses in Lacertids (Family Lacertidae) and Worm Lizards (Amphisbaenia)

    PubMed Central

    Szirovicza, Leonóra; López, Pilar; Kopena, Renáta; Benkő, Mária; Martín, José; Pénzes, Judit J.

    2016-01-01

    Here, we report the results of a large-scale PCR survey on the prevalence and diversity of adenoviruses (AdVs) in samples collected randomly from free-living reptiles. On the territories of the Guadarrama Mountains National Park in Central Spain and of the Chafarinas Islands in North Africa, cloacal swabs were taken from 318 specimens of eight native species representing five squamate reptilian families. The healthy-looking animals had been captured temporarily for physiological and ethological examinations, after which they were released. We found 22 AdV-positive samples in representatives of three species, all from Central Spain. Sequence analysis of the PCR products revealed the existence of three hitherto unknown AdVs in 11 Carpetane rock lizards (Iberolacerta cyreni), nine Iberian worm lizards (Blanus cinereus), and two Iberian green lizards (Lacerta schreiberi), respectively. Phylogeny inference showed every novel putative virus to be a member of the genus Atadenovirus. This is the very first description of the occurrence of AdVs in amphisbaenian and lacertid hosts. Unlike all squamate atadenoviruses examined previously, two of the novel putative AdVs had A+T rich DNA, a feature generally deemed to mirror previous host switch events. Our results shed new light on the diversity and evolution of atadenoviruses. PMID:27399970

  4. The complete mitochondrial genome of a gecko and the phylogeneticposition of the Middle Eastern teratoscincus keyserlingii

    SciTech Connect

    Macey, J. Robert; Fong, Jonathan J.; Kuehl, Jennifer V.; Shafiei,Soheila; Ananjeva, Natalia B.; Papenfuss, Theodore J.; Boore, Jeffrey L.

    2005-04-22

    Sqamate reptiles are traditionally divided into six groups: Iguania, Anguimorpha, Scincomorpha, Gekkota (these four are lizards), Serpentes (snakes), and Amphisbaenia (the so-called worm lizards). Currently there are complete mitochondrial genomes from two representatives of the Iguania (Janke et al., 2001; Kumazawa, 2004), three from the Anguimorpha (Kumazawa, 2004; Kumazawa and Endo, 2004), two from the Scincomorpha (Kumazawa and Nishida, 1999; Kumazawa, 2004), two from Serpentes (Kumazawa et al., 1998; Kumazawa, 2004) and 12 from Amphisbaenia (Macey et al., 2004). The only traditional group of Squamata from which a complete mitochondrial genome has not been sequenced is the Gekkota. Here we report the complete mitochondrial genome of Teratoscincus keyserlingii, a Middle Eastern representative of the Gekkota. The gekkonid lizard genus Teratoscincus is distributed throughout the deserts of central and southwest Asia as shown in figure 1, with five species currently recognized (Macey et al. 1997a, 1999b). Included in this figure are the positions of mountain ranges discussed in the text; see also figure 1 in Macey et al. (1999b). Two species, T. bedriagai and T. microlepis, are restricted to Southwest Asia south of the Kopet Dagh and Hindu Kush in Iran, Afghanistan, and Pakistan (Anderson, 1999). Two species are found in the deserts of western China and Mongolia, with T. przewalskii occurring in the Taklimakan and lowland Gobi deserts, and T. roborowskii restricted to the Turpan Depression. The fifth species, T. scincus, is sometimes considered to be restricted to the Caspian Basin in Kazakhstan, Kyrgyzistan, Tadjikistan, Turkmenistan and Uzbekistan. Alternatively, Teratoscincus populations in Southwest Asia, primarily on the Iranian Plateau, situated directly north of the Arabian Plate, are sometimes considered to be a subspecies of T. scincus or, otherwise, to constitute a sixth species, T. keyserlingii. Macey et al. (1999b) assessed the phylogenetic

  5. The phylogeny of squamate reptiles (lizards, snakes, and amphisbaenians) inferred from nine nuclear protein-coding genes.

    PubMed

    Vidal, Nicolas; Hedges, S Blair

    2005-01-01

    Squamate reptiles number approximately 8000 living species and are a major component of the world's terrestrial vertebrate diversity. However, the established relationships of the higher-level groups have been questioned in recent molecular analyses. Here we expand the molecular data to include DNA sequences, totaling 6192 base pairs (bp), from nine nuclear protein-coding genes (C-mos, RAG1, RAG2, R35, HOXA13, JUN, alpha-enolase, amelogenin and MAFB) for 19 taxa representing all major lineages. Our phylogenetic analyses yield a largely resolved phylogeny that challenges previous morphological analyses and requires a new classification. The limbless dibamids are the most basal squamates. Of the remaining taxa (Bifurcata), the gekkonids form a basal lineage. The Unidentata, squamates that are neither dibamids nor gekkonids, are divided into the Scinciformata (scincids, xantusiids, and cordylids) and the Episquamata (remaining taxa). Episquamata includes Laterata (Teiformata, Lacertiformata, and Amphisbaenia, with the latter two joined in Lacertibaenia) and Toxicofera (iguanians, anguimorphs and snakes). Our results reject several previous hypotheses that identified either the varanids, or a burrowing lineage such as amphisbaenians or dibamids, as the closest relative of snakes. Our study also rejects the monophyly of both Scleroglossa and Autarchoglossa, because Iguania, a species-rich lineage (ca. 1440 sp.), is in a highly nested position rather than being basal among Squamata. Thus iguanians should not be viewed as representing a primitive state of squamate evolution but rather a specialized and successful clade combining lingual prehension, dependence on visual cues, and ambush foraging mode, and which feeds mainly on prey avoided by other squamates. Molecular time estimates show that the Triassic and Jurassic (from 250 to 150 Myr) were important times for squamate evolution and diversification.

  6. Polydactyly in the central pacific gecko, Lepidodactylus sp. (Squamata: Gekkonidae)

    USGS Publications Warehouse

    Bauer, A.M.; Hathaway, S.A.; Fisher, R.N.

    2009-01-01

    We report the first known case of naturally occurring polydactyly in a gekkotan lizard. A single individual from Palmyra Atoll exhibited a triplication of digit III of the m hand. No obvious teratogenic sources are present on the atoll and the causal factors of polydactyly in Lepidodactylus sp. remain unknown.

  7. Dentition and tooth replacement pattern in Chalcides (Squamata; Scincidae).

    PubMed

    Delgado, Sidney; Davit-Beal, Tiphaine; Sire, Jean-Yves

    2003-05-01

    This study was undertaken as a prerequisite to investigations on tooth differentiation in a squamate, the Canarian scincid Chalcides. Our main goal was to determine whether the pattern of tooth replacement, known to be regular in lizards, could be helpful to predict accurately any stage of tooth development. A growth series of 20 laboratory-reared specimens, aged from 0.5 month after birth to about 6 years, was used. The dentition (functional and replacement teeth) was studied from radiographs of jaw quadrants. The number of tooth positions, the tooth number in relation to age and to seasons, and the size of the replacement teeth were recorded. In Chalcides, a single row of pleurodont functional teeth lies at the labial margin of the dentary, premaxillary, and maxillary. Whatever the age of the specimens, 16 tooth positions were recorded, on average, in each quadrant, suggesting that positions are maintained throughout life. Replacement teeth were numerous whatever the age and season, while the number of functional teeth was subject to variation. Symmetry of tooth development was evaluated by comparing teeth two by two from the opposite side in the four jaw quadrants of several specimens. Although the relative size of some replacement teeth fitted perfectly, the symmetry criterion was not reliable to predict the developmental stage of the opposite tooth, whether the pair of teeth compared was left-right or upper-lower. The best fit was found when comparing the size of successive replacement teeth from the front to the back of the jaw. Every replacement tooth that is 40-80% of its definitive size is followed, in the next position on the arcade, by a tooth that is, on average, 20% less developed. Considering teeth in alternate positions (even and odd series), each replacement tooth was a little more developed than the previous, more anterior, one (0.5-20% when the teeth are from 10-40% of their final size). The latter pattern showed that tooth replacement occurred in alternate positions from back to front, forming more or less regular rows (i.e., "Zahnreihen"). In Chalcides, the developmental stage of a replacement tooth in a position p can be accurately predicted provided the developmental stage of the replacement tooth in position p-1 or, to a lesser degree, in position p-2 is known. This finding will be particularly helpful when starting our structural and ultrastructural studies of tooth differentiation in this lizard.

  8. Gekko aaronbaueri, a new gecko (Squamata: Gekkonidae) from central Laos.

    PubMed

    Tri, Ngo Van; Thai, Pham Hong; Phimvohan, Anorath; David, Patrick; Teynié, Alexandre

    2015-01-27

    A new species of the genus Gekko Laurenti is described from central Laos. The species is distinguished from its congeners by its moderate size, i.e. maximum SVL 80.0 mm, dorsal pattern of five to six dirty white vertebral spots alternating with yellowish-edged, W-shaped blotches between nape and sacrum and six to seven pairs of dirty white spots interspersed with yellowish-edged dark blotches on the flanks between limb insertions, 0-1 internasal, 39-43 ventral scale rows between the weakly developed ventrolateral folds, 3-4 precloacal pores in males, sometimes separated by one poreless scale, 98-104 smooth dorsal scale rows around the body, 16 broad lamellae beneath digit I of pes, 15-16 broad lamellae beneath digit IV of pes, and enlarged subcaudal scales. 

  9. Skull anatomy of the miniaturized gecko Sphaerodactylus roosevelti (Squamata: Gekkota).

    PubMed

    Daza, Juan D; Abdala, Virginia; Thomas, Richard; Bauer, Aaron M

    2008-11-01

    A detailed description of the skull and jaw of the gecko Sphaerodactylus roosevelti is presented. The bones are described articulated and isolated with special consideration given to the type of suture among joining elements. S. roosevelti was compared with 109 gekkotan species to evaluate the osteological variation and to find characters for cladistic analysis. Changes in the skull associated with the miniaturization process are discussed within the sphaerodactylid geckos. A noticeable increase of overlapping sutures was observed in the snout of the smallest sphaerodactylids compared to other gekkotans. This pattern is convergent with that in miniaturized pygopodids and may be attributed to adaptations for decreasing mechanical resistance of the cranium during feeding or burrowing. New cranial characters support Sphaerodactylinae as a monophyletic group and should be useful for resolving questions such as their relationship with other gekkotans.

  10. Complete mitochondrial genome of Sinovipera sichuanensis (Reptilia: Squamata: Viperidae).

    PubMed

    Zhu, Fei; Liu, Qin; Zhong, Guanghui; Xiao, Rong; Fang, Min; Guo, Peng

    2016-09-01

    Sinovipera sichuanensis is one of the Asian green pit vipers with less concern. It is endemic to China and only known in Hejiang, Sichuan Province and Jiangkou, Guizhou Province. In this study, we report the complete mitochondrial genome and characterize each partition. The complete mitochondrial genome is 17 225 bp in length containing 2 rRNAs, 13 protein-coding genes, 2 control regions and 22 tRNAs. We use Bayesian Inference (BI) and Maximum Likelihood (ML) methods to infer the phylogenetic relationship of S. sichuanensis. Both BI and ML analyses strongly support that S. sichuanensis is independent from the other two Asian green pit vipers.

  11. Pythons in Burma: Short-tailed python (Reptilia: Squamata)

    USGS Publications Warehouse

    Zug, George R.; Gotte, Steve W.; Jacobs, Jeremy F.

    2011-01-01

    Short-tailed pythons, Python curtus species group, occur predominantly in the Malayan Peninsula, Sumatra, and Borneo. The discovery of an adult female in Mon State, Myanmar, led to a review of the distribution of all group members (spot-mapping of all localities of confirmed occurrence) and an examination of morphological variation in P. brongersmai. The resulting maps demonstrate a limited occurrence of these pythons within peninsular Malaya, Sumatra, and Borneo with broad absences in these regions. Our small samples limit the recognition of regional differentiation in the morphology of P. brongersmai populations; however, the presence of unique traits in the Myanmar python and its strong allopatry indicate that it is a unique genetic lineage, and it is described as Python kyaiktiyo new species.

  12. A Review of Sex Determining Mechanisms in Geckos (Gekkota: Squamata)

    PubMed Central

    Gamble, T.

    2010-01-01

    Geckos are a species-rich clade of reptiles possessing diverse sex determining mechanisms. Some species possess genetic sex determination, with both male and female heterogamety, while other species have temperature-dependent sex determination. I compiled information from the literature on the taxonomic distribution of these sex determining mechanisms in geckos. Using phylogenetic data from the literature, I reconstructed the minimum number of transitions among these sex determining mechanisms with parsimony-based ancestral state reconstruction. While only a small number of gecko species have been characterized, numerous changes among sex determining mechanisms were inferred. This diversity, coupled with the high frequency of transitions, makes geckos excellent candidates as a model clade for the study of vertebrate sex determination and evolution. PMID:20234154

  13. Earliest Example of a Giant Monitor Lizard (Varanus, Varanidae, Squamata)

    PubMed Central

    Conrad, Jack L.; Balcarcel, Ana M.; Mehling, Carl M.

    2012-01-01

    Background Varanidae is a clade of tiny (<20 mm pre-caudal length [PCL]) to giant (>600 mm PCL) lizards first appearing in the Cretaceous. True monitor lizards (Varanus) are known from diagnostic remains beginning in the early Miocene (Varanus rusingensis), although extremely fragmentary remains have been suggested as indicating earlier Varanus. The paleobiogeographic history of Varanus and timing for origin of its gigantism remain uncertain. Methodology/Principal Findings A new Varanus from the Mytilini Formation (Turolian, Miocene) of Samos, Greece is described. The holotype consists of a partial skull roof, right side of a braincase, partial posterior mandible, fragment of clavicle, and parts of six vertebrae. A cladistic analysis including 83 taxa coded for 5733 molecular and 489 morphological characters (71 previously unincluded) demonstrates that the new fossil is a nested member of an otherwise exclusively East Asian Varanus clade. The new species is the earliest-known giant (>600 mm PCL) terrestrial lizard. Importantly, this species co-existed with a diverse continental mammalian fauna. Conclusions/Significance The new monitor is larger (longer) than 99% of known fossil and living lizards. Varanus includes, by far, the largest limbed squamates today. The only extant non-snake squamates that approach monitors in maximum size are the glass-snake Pseudopus and the worm-lizard Amphisbaena. Mosasauroids were larger, but exclusively marine, and occurred only during the Late Cretaceous. Large, extant, non-Varanus, lizards are limbless and/or largely isolated from mammalian competitors. By contrast, our new Varanus achieved gigantism in a continental environment populated by diverse eutherian mammal competitors. PMID:22900001

  14. Complete mitochondrial genome of Goniurosaurus luii (Squamata, Eublepharidae).

    PubMed

    Li, Hui-Min; Hou, Li-Xia; Zhang, Yu; Guo, Dan-Ni; Liu, Yu-Jie; Qin, Xin-Min

    2016-05-01

    The complete mitochondrial genome sequence of Goniurosaurus luii has been determined in the present paper. The genome was 16,519 bp in length and contained 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and 1 control region (CR). Its gene composition and order was similar to most other Squamate reptiles. The overall base composition of the genome in descending order was 34.11% A, 26. 01% C, 27.43% T, and 12.45% G, with a slight AT bias of 61.54%. CR was located between the tRNA-Pro and tRNA-Phe genes and was 1147 bp in length, some tandem repeat sequences and conserved elements (CSB2-3) were found in the control region.

  15. Acanthocephala Larvae parasitizing Ameiva ameiva ameiva (Linnaeus, 1758) (Squamata: Teiidae).

    PubMed

    Macedo, Lilian Cristina; Melo, Francisco Tiago de Vasconcelos; Ávila-Pires, Teresa Cristina Sauer; Giese, Elane Guerreiro; Santos, Jeannie Nascimento Dos

    2016-03-11

    Knowledge concerning the taxonomy and biology of species of Acanthocephala, helminth parasites of the helminth species of the phylum Acanthocephala, parasites of lizards in Brazilian Amazonia, is still insufficient, but reports of Acanthocephala in reptiles are becoming increasingly common in the literature. Cystacanth-stage Acanthocephalan larvae have been found in the visceral peritoneum during necropsy of Ameiva ameiva ameivalizards from the "Osvaldo Rodrigues da Cunha" Herpetology Collection of the Emílio Goeldi Museum, Belém, Pará, Brazil. The aim of this study was to present the morphological study of the Acanthocephala larvae found in A. ameiva ameiva lizard.

  16. Acanthocephala Larvae parasitizing Ameiva ameiva ameiva (Linnaeus, 1758) (Squamata: Teiidae).

    PubMed

    Macedo, Lilian Cristina; Melo, Francisco Tiago de Vasconcelos; Ávila-Pires, Teresa Cristina Sauer; Giese, Elane Guerreiro; dos Santos, Jeannie Nascimento

    2016-01-01

    Knowledge concerning the taxonomy and biology of species of Acanthocephala, helminth parasites of the helminth species of the phylum Acanthocephala, parasites of lizards in Brazilian Amazonia, is still insufficient, but reports of Acanthocephala in reptiles are becoming increasingly common in the literature. Cystacanth-stage Acanthocephalan larvae have been found in the visceral peritoneum during necropsy of Ameiva ameiva ameivalizards from the "Osvaldo Rodrigues da Cunha" Herpetology Collection of the Emílio Goeldi Museum, Belém, Pará, Brazil. The aim of this study was to present the morphological study of the Acanthocephala larvae found in A. ameiva ameiva lizard.

  17. The taxonomic status of Tantilla marcovani Lema 2004 (Squamata: Colubridae).

    PubMed

    Mata-Silva, Vicente; Wilson, Larry David

    2016-03-16

    The colubrid snake genus Tantilla currently comprises 62 valid species distributed from the southern United States of America to southern Bolivia in the west, and Uruguay and northern Argentina in the east (Wilson & Mata-Silva 2014, 2015). Of these 62 species, 13 are found in South America (Wilson & Mata-Silva 2014, 2015). The most recently described of these Southamerican species is Tantilla marcovani Lema, 2004. While we were working on a checklist and key to the members of the Tantilla clade (sensu Holm 2008, including the genera Geagras Cope 1876, Scolecophis Fitzinger 1843, Tantilla Baird & Girard 1853, and Tantillita Smith 1941; Wilson & Mata-Silva 2015), it became apparent that the diagnosis of T. marcovani entirely falls to distinguish this nominal taxon from the widespread and extensively variable T. melanocephala Linnaeus 1758. Tantilla melanocephala, as presently envisioned, is the most broadly distributed member of its genus (Wilson & Mena 1980; Savage 2002; Greenbaum et al. 2004), occurring from Panama southward into the major portion of the South American continent, apart from Chile and southern Argentina.

  18. The circumorbital bones of the Gekkota (Reptilia: Squamata).

    PubMed

    Daza, Juan Diego; Bauer, Aaron Matthew

    2010-03-01

    The enormous variation of the orbit in lepidosaurs is better conceptualized in terms of composition and configuration. Broadly, the orbit varies from having totally closed rim to being open posteriorly. Two processes are responsible for changes in the components of the circumorbital series, element loss and fusion. The resulting contacts among elements are the main factors determining orbital configuration. Here, we present a revision of the gekkotan circumorbital bones in the general context of the Lepidosauria. From observations of a sample of 105 species of gekkotans prepared using different techniques, we describe the main changes in the orbit and corroborate the presence or absence of some of the ambiguous elements such as the lacrimal and the jugal. The supraorbital bones of squamates are reviewed and some problems of homology are evaluated using recent phylogenenetic hypothesis.

  19. Morphological variation in the tropical anole, Anolis casildae (Squamata: Polychrotidae).

    PubMed

    Nicholson, K E; Roberto Ibáñez, D; Jaramillo, C A; Lips, K R

    2001-06-01

    We describe morphological variation (scalation and coloration) observed among eight individuals of the Panamanian lizard species Anolis casildae. This variation was not observed in the holotype and aids in identification of this recently described species (originally described on the basis of a single, male specimen). This species occurs only in the Reserva Forestal Fortuna (Chiriquí Province) and the adjacent Bosque Protector Palo Seco (Bocas del Toro Province) in western Panama. Anolis casildae can be distinguished from all other Panamanian anole species via six features: (1) two enlarged superciliary scales (the first larger than the second); (2) an anterior nasal scale in contact with the rostral scale or separated from the rostral by one scale; (3) 6-8 sublabial scales to the center of the eye; (4) 3-4 scales between the supraobital semicircles; (5) unique coloration (4-6 oblique brown bands interspersed by blue-outlined yellow patches; dewlap is a dirty cream color with broad yellow scale rows irregularly interspersed with smaller emerald green scales) and (6) A. casildae occurs from 1,050 to 1,400 m in the Cordillera Central. We also compare our natural history observations of A. casildae to a similar large anole, A. frenatus, a species which we believe A. casildae to be closely related.

  20. Mature Erythrocytes of Iguana iguana (Squamata, Iguanidae) Possess Functional Mitochondria

    PubMed Central

    Di Giacomo, Giuseppina; Campello, Silvia; Corrado, Mauro; Di Giambattista, Livia; Cirotti, Claudia; Filomeni, Giuseppe; Gentile, Gabriele

    2015-01-01

    Electron microscopy analyses of Iguana iguana blood preparations revealed the presence of mitochondria within erythrocytes with well-structured cristae. Fluorescence microscopy analyses upon incubation with phalloidin-FITC, Hoechst 33342 and mitochondrial transmembrane potential (Δψm)-sensitive probe MitoTracker Red indicated that mitochondria i) widely occur in erythrocytes, ii) are polarized, and iii) seem to be preferentially confined at a "perinuclear" region, as confirmed by electron microscopy. The analysis of NADH-dependent oxygen consumption showed that red blood cells retain the capability to consume oxygen, thereby providing compelling evidence that mitochondria of Iguana erythrocytes are functional and capable to perform oxidative phosphorylation. PMID:26367118

  1. Mature Erythrocytes of Iguana iguana (Squamata, Iguanidae) Possess Functional Mitochondria.

    PubMed

    Di Giacomo, Giuseppina; Campello, Silvia; Corrado, Mauro; Di Giambattista, Livia; Cirotti, Claudia; Filomeni, Giuseppe; Gentile, Gabriele

    2015-01-01

    Electron microscopy analyses of Iguana iguana blood preparations revealed the presence of mitochondria within erythrocytes with well-structured cristae. Fluorescence microscopy analyses upon incubation with phalloidin-FITC, Hoechst 33342 and mitochondrial transmembrane potential (Δψm)-sensitive probe MitoTracker Red indicated that mitochondria i) widely occur in erythrocytes, ii) are polarized, and iii) seem to be preferentially confined at a "perinuclear" region, as confirmed by electron microscopy. The analysis of NADH-dependent oxygen consumption showed that red blood cells retain the capability to consume oxygen, thereby providing compelling evidence that mitochondria of Iguana erythrocytes are functional and capable to perform oxidative phosphorylation.

  2. Comparative study of sperm ultrastructure of five species of teiid lizards (Teiidae, Squamata), and Cercosaura ocellata (Gymnophthalmidae, Squamata).

    PubMed

    Colli, G R; Teixeira, R D; Scheltinga, D M; Mesquita, D O; Wiederhecker, H C; Báo, S N

    2007-02-01

    Sperm ultrastructure of five teiid lizards (Callopistes flavipunctatus, Crocodilurus amazonicus, Dicrodon guttulatum, Dracaena guianensis, and Teius oculatus), and the gymnophthalmid Cercosaura ocellata is described for the first time. Comparisons of sperm ultrastructure among these species and with those of previously examined teiids and gymnophthalmids revealed that the two groups of Teiioidea (Gymnophthalmidae and Teiidae), and the two subfamilies of Teiidae (Teiinae and Tupinambinae) could be distinguished on the basis of sperm ultrastructure data. Significant differences in sperm dimensions between Cnemidophorus and Aspidoscelis support the recent splitting of these two lineages into different genera. Our results revealed high levels of inter-generic variability in sperm ultrastructure within Teiidae, which produces a data set useful in analyzing relationships between genera and families. In phylogenetic analyses, however, sampling multiple species within teiid genera is essential and recording sperm measurements may profitably complement qualitative ultrastructural characters, maximizing the information content of these structures.

  3. Two new Liolaemus lizards from the Andean highlands of Southern Chile (Squamata, Iguania, Liolaemidae).

    PubMed

    Troncoso-Palacios, Jaime; Diaz, Hugo A; Puas, German I; Riveros-Riffo, Edvin; Elorza, Alvaro A

    2016-01-01

    Liolaemus is a diverse genus of lizards, subdivided into two subgenera: Liolaemus (sensu stricto) and Eulaemus, distributed mainly in Chile and Argentina. The Liolaemus elongatus-kriegi complex is the most diverse group within Liolaemus (sensu stricto), especially the species closely related to Liolaemus elongatus, which form a clade currently comprising nine species. Several Chilean species of this group have been recently described, mainly from volcanoes and poorly explored mountains. Here molecular and morphological evidence are provided for a new species of the Liolaemus elongatus clade, which is characterized by its small size and lack of dorsal pattern, unusual features for the species of this group of lizards. Additionally, the lack of precloacal pores in males of Liolaemus (sensu stricto) is a trait found in few species, which do not constitute a monophyletic group. A second new southern Chilean species is also described, without precloacal pores and supported by molecular phylogenetics to be related to Liolaemus villaricensis. Both new species were found in the same locality, near a lake located in a pre-Andean zone with Araucaria and Nothofagus forest. The two species are dedicated to prominent Lonkos (tribal chiefs) of the Mapuche and Pehuenche people: Janequeo and Leftraru. Additionally, the phylogenetic results suggest that Liolaemus lonquimayensis is a synonym of Liolaemus elongatus.

  4. Differential staining and microchromosomal variation in karyotypes of four Brazilian species of Tupinambinae lizards (Squamata: Teiidae).

    PubMed

    dos Santos, Rodrigo Marques Lima; Rodrigues, Miguel Trefaut; Yonenaga-Yassuda, Yatiyo; Pellegrino, Katia Cristina Machado

    2008-11-01

    Kayotypes of four neotropical teiid lizard species (Tupinambinae) were herein studied after conventional as well as silver staining and CBG-banding: Crocodilurus amazonicus (2n = 34), Tupinambis teguixin (2n = 36), Tupinambis merianae and Tupinambis quadrilineatus (2n = 38). The karyological data for T. quadrilineatus as well as those obtained using differential staining for all species were unknown until now. The karyotypes of all species presented 12 macrochromosomes identical in morphology, but differed in the number of microchromosomes: 22 in C. amazonicus, 24 in T. teguixin and 26 in T. quadrilineatus and T. merianae. The Ag-NOR located at the secondary constriction at the distal end of pair 2 is shared by all species, contrasting with the variability observed for this character in species of the related Teiinae. CBG-banding revealed a species-specific pattern in T. quadrilineatus with conspicuous interstitial C-blocks at the proximal region of the long arm of pair 4 and the whole heterochromatic short arm of pair 6. The karyological data reported here corroborates the relationship hypothesis obtained for Tupinambis based on molecular characters. T. teguixin presents the putative ancestral karyotype for the genus with 2n = 36 whereas T. merianae and T. quadrilineatus exhibit 2n = 38, due to an additional pair of microchromosomes.

  5. Microchromosome polymorphism in the sand lizard, Lacerta agilis Linnaeus, 1758 (Reptilia, Squamata)

    PubMed Central

    Lisachov, Artem P.; Borodin, Pavel M.

    2016-01-01

    Abstract Most true lizards (Lacertidae) share a conservative karyotype, consisting of 18 pairs of macrochromosomes and one microchromosome pair. Homeologues of the microchromosome are present in other squamates and even in chickens. No structural autosomal microchromosome polymorphisms have been described previously in lizards. We found homozygous and heterozygous carriers of a microchromosome variant in a Siberian population of the sand lizard, Lacerta agilis Linnaeus, 1758. The variant microchromosome was almost twice as long as the standard one. In heterozygotes at pachytene, the microchromosomes firstly pair in proximal regions and the central part of the longer axial element undergoes foldback synapsis, then its distal region pairs with the distal region of the standard partner. At metaphase-I, the heteromorphic microchromosome bivalents have a proximal chiasma. The content of the additional segment was Ag-NOR, C-like DAPI, CMA3 negative. FISH with telomere PNA probe did not detect interstitial (TTAGGG)n sequences in the heteromorphic and any other bivalents. Both homo- and heterozygous carriers were phenotypically normal. The presence of homozygotes shows that heterozygotes are fertile. Reduction in the number of microchromosomes is a clear trend in squamate evolution, as a result of microchromosomes fusing together or with macrochromosomes. Our findings indicate that gaining additional DNA may lead to a transformation of microchromosomes into small macrochromosomes without fusion. PMID:27830048

  6. Resolving the phylogeny of lizards and snakes (Squamata) with extensive sampling of genes and species.

    PubMed

    Wiens, John J; Hutter, Carl R; Mulcahy, Daniel G; Noonan, Brice P; Townsend, Ted M; Sites, Jack W; Reeder, Tod W

    2012-12-23

    Squamate reptiles (lizards and snakes) are one of the most diverse groups of terrestrial vertebrates. Recent molecular analyses have suggested a very different squamate phylogeny relative to morphological hypotheses, but many aspects remain uncertain from molecular data. Here, we analyse higher-level squamate phylogeny with a molecular dataset of unprecedented size, including 161 squamate species for up to 44 nuclear genes each (33 717 base pairs), using both concatenated and species-tree methods for the first time. Our results strongly resolve most squamate relationships and reveal some surprising results. In contrast to most other recent studies, we find that dibamids and gekkotans are together the sister group to all other squamates. Remarkably, we find that the distinctive scolecophidians (blind snakes) are paraphyletic with respect to other snakes, suggesting that snakes were primitively burrowers and subsequently re-invaded surface habitats. Finally, we find that some clades remain poorly supported, despite our extensive data. Our analyses show that weakly supported clades are associated with relatively short branches for which individual genes often show conflicting relationships. These latter results have important implications for all studies that attempt to resolve phylogenies with large-scale phylogenomic datasets.

  7. Are hemipenial spines related to limb reduction? A spiny discussion focused on gymnophthalmid lizards (Squamata: Gymnophthalmidae).

    PubMed

    Sales Nunes, Pedro M; Curcio, Felipe F; Roscito, Juliana G; Rodrigues, Miguel T

    2014-03-01

    Calcified spines in the hemipenial surface occur convergently in several gymnophthalmid lizard species and in advanced snakes. Based on the pronounced degrees of limb reduction in these distantly related lineages, such hemipenial structures were suggested to play a functional role in couple-anchoring during copulation, partly assuming the function of the limbs during mating. Herein, we assessed the hemipenial morphology of virtually all the valid genera of the family Gymnophthalmidae to test for a phylogenetic correlation between limb reduction and the presence of calcified hemipenial spines. The occurrence of calcified structures was mapped on the two most comprehensive phylogenies of the family. We concluded that spiny hemipenes are by no means necessarily associated with reduction of limbs. Conversely, the presence of well-developed hemipenial spines in specific limb-reduced taxa does not allow one to disregard the possibility that in some instances such structures might indeed be functionally associated with couple-anchoring, improving the success of mating.

  8. A Phylogenetic, Biogeographic, and Taxonomic study of all Extant Species of Anolis (Squamata; Iguanidae).

    PubMed

    Poe, Steven; Nieto-Montes de Oca, Adrián; Torres-Carvajal, Omar; de Queiroz, Kevin; Velasco, Julián A; Truett, Brad; Gray, Levi N; Ryan, Mason J; Köhler, Gunther; Ayala-Varela, Fernando; Latella, Ian

    2017-02-27

    Anolis lizards (anoles) are textbook study organisms in evolution and ecology. Although several topics in evolutionary biology have been elucidated by the study of anoles, progress in some areas has been hampered by limited phylogenetic information on this group. Here we present a phylogenetic analysis of all 379 extant species of Anolis, with new phylogenetic data for 139 species including new DNA data for 101 species. We use the resulting estimates as a basis for defining anole clade names under the principles of phylogenetic nomenclature and to examine the biogeographic history of anoles. Our new taxonomic treatment achieves the supposed advantages of recent subdivisions of anoles that employed ranked Linnaean-based nomenclature while avoiding the pitfalls of those approaches regarding artificial constraints imposed by ranks. Our biogeographic analyses demonstrate complexity in the dispersal history of anoles, including multiple crossings of the Isthmus of Panama, two invasions of the Caribbean, single invasions to Jamaica and Cuba, and a single evolutionary dispersal from the Caribbean to the mainland that resulted in substantial anole diversity. Our comprehensive phylogenetic estimate of anoles should prove useful for rigorous testing of many comparative evolutionary hypotheses.

  9. Resurrection of Anolis ustus Cope, 1864 from synonymy with Anolis sericeus Hallowell, 1856 (Squamata, Dactyloidae).

    PubMed

    Lara-Tufiño, José Daniel; de Oca, Adrián Nieto-Montes; Ramírez-Bautista, Aurelio; Gray, Levi N

    2016-01-01

    In this study, based on a morphological analysis, the resurrection of the name Anolis ustus Cope 1864, is proposed for populations from the Yucatán Peninsula (Campeche, Yucatán, and Quintana Roo, Mexico, and Belize), formerly referred as Anolis sericeus Hallowell, 1856. Anolis ustus differs from Anolis sericeus by its mean snout-vent length and number of gorgetal scales in males, in tibia length and head width in females, and dorsal and ventral scales for both sexes. In addition, Anolis ustus has a small dewlap of similar size between males and females, whereas in Anolis sericeus males have a dewlap much larger than that of the females. These characteristics allow Anolis ustus to be identified within the Anolis sericeus complex. In this study, a description of the characteristics of the hemipenis is also provided, and its importance in the taxonomy of Anolis is discussed.

  10. Taxonomic identity of two enigmatic aquatic snake populations (Squamata: Homalopsidae: Cerberus and Homalopsis) from southern Thailand.

    PubMed

    Pauwels, Olivier S G; Sumontha, Montri

    2016-05-02

    In their revision of the homalopsid genus Homalopsis Kuhl & Van Hasselt, Murphy et al. (2012) resurrected H. semizonata Blyth, 1855 and noted that ''Frith (1977) reported on two Homalopsis from Phuket, Thailand with 40 and 42 dorsal scale rows, and 159 and 162 ventrals-scale counts within the range of H. semizonata which is found along the same coast, about 900 km to the north''. Murphy et al. (2012), however, did not list H. semizonata from Thailand, and on their species' distribution map they indicated an interrogation mark along the southern coast of Myanmar and the southwestern coast of peninsular Thailand. It should be noted that Murphy et al. (2012) misread Frith: while one of the two specimens reported by Frith was indeed from Phuket (''from the rocky edge of a stream torrent in good forest east of Thalang, central Phuket Island''), the other was from ''Klong Nakha, 80 kilometeres [sic] south of Ranong in lowland rain forest with some clearings and dwellings'', thus in Ranong Province, closer to the border with Myanmar. Nabhitabhata et al. (2004) recognized a single Homalopsis species in Thailand, H. buccata, which they listed for numerous provinces, including Phuket, based on Frith's (1977) record. Among the two Homalopsis species recognized to occur in Thailand by Nabhitabhata and Chan-ard (2005), H. buccata and H. nigroventralis, none was recorded by them from Phuket Province, but H. buccata was listed from, among others, the neighbouring provinces of Phang-Nga and Ranong. Chuaynkern & Chuaynkern (2012) recognized the same two species, and listed H. buccata from, among others, the provinces of Phang-Nga, Phuket and Ranong. Cox et al. (2012) listed three Homalopsis for Thailand (H. buccata, H. mereljcoxi and H. nigroventralis), and indicated that H. mereljcoxi is the species occurring, a.o., in Phang-Nga, Phuket and Ranong provinces. Wallach et al. (2014) noted that H. semizonata lives in southern Myanmar near sea level, but also that it ''possibly occurs in Phuket''. Chan-ard et al. (2015), in their field guide whose reptile taxonomy is largely outdated (Pauwels & Grismer 2015), recognized only Homalopsis nigroventralis and H. buccata and the map for the latter indicates its presence in Phuket and Phang-Nga provinces. In the most recent synthesis on the family Homalopsidae, Murphy & Voris (2014) made however no mention of the possibility that H. semizonata occurs in Thailand. Because of the lack of voucher material, the identity of the Homalopsis living on the Indian Ocean coastal area of Thailand has thus remained poorly understood so far.

  11. A novel species of Euspondylus (Squamata: Gymnophthalmidae) from the Andes Mountains of central Peru.

    PubMed

    Doan, Tiffany M; Adams, Grant

    2015-10-21

    The South American gymnophthalmid genus Euspondylus is distributed from Venezuela through Peru, with its highest diversity occurring in Peru. Euspondylus paxcorpus sp. nov. is a new species from Junín, Peru possessing prefrontal scales and represented by 60 specimens. The new species differs from all other species by the combination of four supraoculars with supraocular/supraciliary fusion, 5-7 occipitals, a single palpebral scale, five supralabials and infralabials, quadrangular dorsal scales with low keels arranged in transverse series only, 40-45 in a longitudinal count and 22-28 in a transverse count, 12 rows of ventrals in a transverse count and 23-25 in a longitudinal count, and no sexual dimorphism in coloration. The discovery of E. paxcorpus increases the known number of Euspondylus species to 13. Because the coloration patterns of the specimens were greatly different after preservation in alcohol, caution should be used when identifying Euspondylus species from museum specimens.

  12. Taxonomy, phylogeny, and distribution of Bronchocela rayaensis (Squamata: Agamidae) on the Thai-Malay Peninsula.

    PubMed

    Grismer, L Lee; Wood, Perry L Jr; Aowphol, Anchelee; Cota, Michael; Murdoch, Mathew L; Aguilar, César; Grismer, Marta S

    2016-03-16

    An integrative taxonomic analysis used to identify a new population of Bronchocela from Phuket Island, Thailand indicates it is conspecific with B. rayaensis from the Langkawi Archipelago of northwestern Peninsular Malaysia. An additional specimen photographed from Khura Buri District, Phang-nga Province is also considered to be B. rayaensis and represents a northern range extension of 295 km from the Langkawi Archipelago.

  13. A new species of Bachia Gray, 1845 (Squamata: Gymnophthalmidae) from the western Brazilian Amazonia.

    PubMed

    Teixeira, Mauro; Dal Vechio, Francisco; Nunes, Pedro M Sales; Mollo Neto, Antonio; Lobo, Luciana Moreira; Storti, Luis Fernando; Junqueira, Renato Augusto; Dias, Pedro Henrique Freire; Rodorigues, Miguel Trefaut

    2013-01-01

    A new species of Bachia of the B. dorbignyi group, Bachia scaea sp. nov., is described from the left bank of the upper Madeira River, at Rondônia state, at the western Brazilian Amazonia. The new species resembles morphologically B. dorbignyi and B. peruana, and seems to be related with the former species based on molecular data (16S and c-mos sequences). Nonetheless the presence of a first temporal separating parietal and supralabial scales and the absence of clawed fingers in the new species, can promptly distinguish it from their close relatives. This description ends with several-decades of stasis in the taxonomy of the Bachia dorbignyi group from Amazonian lowlands, and also presents new evidence that supports the Madeira River as a vicariant barrier.

  14. Resurrection of Bronchocela burmana Blanford, 1878 for the Green Crested Lizard (Squamata, Agamidae) of southern Myanmar

    PubMed Central

    Zug, George R.; Mulcahy, Daniel G.; Vindum, Jens V.

    2017-01-01

    Abstract Recent fieldwork in southern Tanintharyi revealed the presence of a small Green Crested Lizard in the wet evergreen forest. We generated mtDNA sequence data (ND2) that demonstrates that this population’s nearest relative is Bronchocela rayaensis Grismer et al., 2015 of Pulau Langkawi, northwestern Peninsular Malaysia and Phuket Island. Morphologically the Burmese Bronchocela shares many features with Bronchocela rayaensis, which potentially would make this recently described Thai-Malay species a synonym of Bronchocela burmana Blanford, 1878; however, we interpret the genetic and morphological differences to reflect evolutionary divergence and recommend the recognition of both species. PMID:28331413

  15. Cryptic lineages and diversification of an endemic anole lizard (Squamata, Dactyloidae) of the Cerrado hotspot.

    PubMed

    Guarnizo, Carlos E; Werneck, Fernanda P; Giugliano, Lilian G; Santos, Marcella G; Fenker, Jéssica; Sousa, Lucas; D'Angiolella, Annelise B; Dos Santos, Adriana R; Strüssmann, Christine; Rodrigues, Miguel T; Dorado-Rodrigues, Tainá F; Gamble, Tony; Colli, Guarino R

    2016-01-01

    The Cerrado is a wide Neotropical savanna with tremendously high endemic diversity. Yet, it is not clear what the prevalent processes leading to such diversification are. We used the Cerrado-endemic lizard Norops meridionalis to investigate the main abiotic factors that promoted genetic divergence, the timings of these divergence events, and how these relate to cryptic diversity in the group. We sequenced mitochondrial and nuclear genes from 21 sites of N. meridionalis to generate species tree, divergence time estimations, and estimate species limits. We also performed population-level analysis and estimated distribution models to test the roles of niche conservatism and divergence in the group diversification. We found that N. meridionalis is composed by at least five cryptic species. Divergence time estimations suggest that the deepest branches split back into the early-mid Miocene, when most of the geophysical activity of the Cerrado took place. The deep divergences found in N. meridionalis suggest that beta anoles invaded South America much earlier than previously thought. Recent published evidence supports this view, indicating that the Panama gap closed as early as 15 mya, allowing for an early invasion of Norops into South America. The spatial pattern of diversification within N. meridionalis follows a northwest-southeast direction, which is consistent across several species of vertebrates endemic to the Cerrado. Also, we found evidence for non-stationary isolation by distance, which occurs when genetic differentiation depends on space. Our preliminary data in two out of five lineages suggest that niche conservatism is an important mechanism that promoted geographic fragmentation in the group.

  16. Cryptic extinction of a common Pacific lizard Emoia impar (Squamata, Scincidae) from the Hawaiian Islands.

    USGS Publications Warehouse

    Fisher, Robert; Ineich, Ivan

    2012-01-01

    Most documented declines of tropical reptiles are of dramatic or enigmatic species. Declines of widespread species tend to be cryptic. The early (1900s) decline and extinction of the common Pacific skink Emoia impar from the Hawaiian Islands is documented here through an assessment of literature, museum vouchers and recent fieldwork. This decline appears contemporaneous with the documented declines of invertebrates and birds across the Hawaiian Islands. A review of the plausible causal factors indicates that the spread of the introduced big-headed ant Pheidole megacephala is the most likely factor in this lizard decline. The introduction and spread of a similar skink Lampropholis delicata across the islands appears to temporally follow the decline of E. impar, although there is no evidence of competition between these species. It appears that L. delicata is spreading to occupy the niche vacated by the extirpated E. impar. Further confusion exists because the skink E. cyanura, which is very similar in appearance to E. impar, appears to have been introduced to one site within a hotel on Kaua'i and persisted as a population at that site for approximately 2 decades (1970s–1990s) but is now also extirpated. This study highlights the cryptic nature of this early species extinction as evidence that current biogeographical patterns of non-charismatic or enigmatic reptiles across the Pacific may be the historical result of early widespread invasion by ants. Conservation and restoration activities for reptiles in the tropical Pacific should consider this possibility and evaluate all evidence prior to any implementation.

  17. A new Cyrtodactylus (Squamata: Gekkonidae) from Khanh Hoa Province, southern Vietnam.

    PubMed

    Schneider, Nicole; Phung, Trung My; Le, Minh Duc; Nguyen, Truong Quang; Ziegler, Thomas

    2014-04-07

    We describe a new species of the genus Cyrtodactylus from southern Vietnam, based on morphological and molecular datasets. Cyrtodactylus cucdongensis sp. nov. is described on the basis of seven specimens collected from Cuc Dong Cape, Khanh Hoa Province. The new species can be distinguished from the remaining bent-toed geckos by a combination of the following characters: maximum SVL 65.9 mm; 16-19 dorsal tubercle rows; 41-44 ventral scales at midbody; 5 or 6 precloacal pores in males, 4-6 pitted precloacal scales in females; no femoral pores; 6-13 enlarged precloacal scales; 5-9 enlarged femoral scales; no transversally enlarged subcaudals; dorsal pattern consisting of irregular dark bands. This is the 33rd species of Cyrtodactylus known from Vietnam.

  18. Two new Liolaemus lizards from the Andean highlands of Southern Chile (Squamata, Iguania, Liolaemidae)

    PubMed Central

    Troncoso-Palacios, Jaime; Diaz, Hugo A.; Puas, German I.; Riveros-Riffo, Edvin; Elorza, Alvaro A.

    2016-01-01

    Abstract Liolaemus is a diverse genus of lizards, subdivided into two subgenera: Liolaemus (sensu stricto) and Eulaemus, distributed mainly in Chile and Argentina. The Liolaemus elongatus-kriegi complex is the most diverse group within Liolaemus (sensu stricto), especially the species closely related to Liolaemus elongatus, which form a clade currently comprising nine species. Several Chilean species of this group have been recently described, mainly from volcanoes and poorly explored mountains. Here molecular and morphological evidence are provided for a new species of the Liolaemus elongatus clade, which is characterized by its small size and lack of dorsal pattern, unusual features for the species of this group of lizards. Additionally, the lack of precloacal pores in males of Liolaemus (sensu stricto) is a trait found in few species, which do not constitute a monophyletic group. A second new southern Chilean species is also described, without precloacal pores and supported by molecular phylogenetics to be related to Liolaemus villaricensis. Both new species were found in the same locality, near a lake located in a pre-Andean zone with Araucaria and Nothofagus forest. The two species are dedicated to prominent Lonkos (tribal chiefs) of the Mapuche and Pehuenche people: Janequeo and Leftraru. Additionally, the phylogenetic results suggest that Liolaemus lonquimayensis is a synonym of Liolaemus elongatus. PMID:27920609

  19. Life expectancy and longevity of varanid lizards (Reptilia:Squamata:Varanidae) in North American zoos.

    PubMed

    Mendyk, Robert W

    2015-01-01

    In zoos, life expectancy-the average lifespan of individuals within a population, and longevity-the maximum lifespan within a population, can be useful parameters for evaluating captive husbandry and animal welfare. Using life history and demographic data derived from regional studbooks, this study examined life expectancy and longevity in a total of 782 wild-caught (WC) and captive-bred (CB) varanid lizards of seven species maintained in North American zoos since 1926. The average lifespans for WC and CB animals were 6.3 ± 0.3 and 9.3 ± 0.4 years, respectively, with CB males living significantly longer than females (P = 0.009). A total of 26.4% of WC and 22.5% of CB animals experienced mortality during their first 2 years in captivity, with mortality during this period greatest among Varanus rudicollis and V. prasinus. A positive correlation was observed between life expectancy and adult body mass in captive-bred individuals (r = 0.981; P = 0.002). Wild-caught females with a history of successful reproduction had a significantly greater average lifespan than non-reproducing females (P < 0.0001). Results from this study suggest that varanids have not been reaching their lifespan capacities in North American zoos. In light of these findings, several husbandry-related factors which may be affecting the welfare and lifespans of varanids in zoos are identified and discussed. This study also highlights the utility of demographic and life history data in captive animal management, and offers a general framework for future herpetological studies of a similar nature.

  20. Baseline values of micronuclei and comet assay in the lizard Tupinambis merianae (Teiidae, Squamata).

    PubMed

    Schaumburg, Laura G; Poletta, Gisela L; Siroski, Pablo A; Mudry, Marta D

    2012-10-01

    The Micronucleus test (MN) and Comet assay (CA) are currently the most widely used methods that allow the characterization of DNA damage induced by physical and chemical agents in wild species. The continuous expansion of the cultivated areas in Argentina, since the introduction of transgenic crops, mainly soy, in association with the increased use of pesticides, transformed deeply the natural environments where the lizard Tupinambis merianae (tegu lizard) occurs. Despite the fact that reptiles have shown to be excellent bioindicators of environmental contaminants, there is no record of genotoxicity studies in T. merianae. The aim of the present study was to adjust the MN test and CA protocols to be applied in erythrocytes of T. merianae, and determine the baseline values of DNA damage in this species. We used 20 adult lizards (10 males: 10 females) from Estación Zoológica Experimental "Granja La Esmeralda" (Santa Fe, Argentina). Peripheral blood samples were collected from all animals and the MN test and CA applied according to the protocols established for other reptilian species. We test critical parameters of CA protocol (cell density, unwinding and electrophoresis times) using increasing concentrations of H2O2 (10, 25 and 50 μM) as a known genotoxic agent to induce DNA damage. Based on this, we determined the most suitable conditions for the CA in this species: a cell density of 4×10(3) erythrocytes per slide, 10 min of unwinding and 15 min of electrophoresis at 0.90 V/cm approximately. The baseline frequency of micronuclei (BFMN=MN/1000 erythrocytes counted) determined for this species was 0.95±0.27 and the basal damage index (BDI: calculated from 100 comet images classified in arbitrary units)=103.85±0.97. No differences were observed between sexes in the BFMN or BDI (p>0.05), and no relation was found between baseline values and length or weight of the analyzed animals (p>0.05). These results demonstrated the sensitivity of both biomarkers of genotoxicity to be applied in erythrocytes of this species, with baseline values comparable to those reported in other reptilian species. These results allow us to propose the tegu lizard for future in vivo studies to assess the genotoxicity of different agents, including those possibly affecting it in its natural geographic distribution.

  1. Brumation of introduced Black and White Tegus, Tupinambis merianae (Squamata: Teiidae), in southern Florida

    USGS Publications Warehouse

    McEachern, Michelle; Yackel Adams, Amy A.; Klug, Page E.; Fitzgerald, Lee A; Reed, Robert N.

    2015-01-01

    An established population of Tupinambis merianae (Black and White Tegu) in southeastern Florida threatens the Everglades ecosystem. Understanding the behavioral ecology of Black and White Tegus could aid in management and control plans. Black and White Tegus are seasonally active and brumate during the winter in their native range, but brumation behavior is largely unstudied in either the native or the invasive range. We describe the first observations of Black and White Tegu brumation in southeastern Florida after monitoring 5 free-ranging, adult male Black and White Tegus through an inactive season using radiotelemetry and automated cameras. Duration of brumation averaged 137 days, beginning in September and ending by February. One of the 5 Black and White Tegus emerged to bask regularly during brumation, which to our knowledge represents the first documented instance of a free-ranging Black and White Tegu basking during brumation. These preliminary findings provide a basis for future research o f brumation behavior.

  2. The effects of early experience on subsequent feeding responses in the Tegu, Tupinambis teguixin (Squamata : Teiidae).

    PubMed

    Punzo, F

    2003-01-01

    The purpose of this study was to assess the effects of early feeding experiences on subsequent responses to prey in the tegu, Tupinambis teguixin. Five-day old lizards were exposed to the odors of various prey and control substances on cotton-tipped applicators with the tongue-flick attack score (TFAS) chosen as the dependent variable. Each lizard was exposed to four stimuli: two controls (deionised water and cologne), and extracts from a mouse Mus musculus, and a lizard Ameiva ameiva, in a repeated measures, randomized block design, receiving one stimulus training session / day over a 40-day period. Tongue-flicks directed toward the applicator were counted over a 1 min period as well as the amount of time that elapsed from the first tongue flick to any bite that may have occurred. Live neonatal mice (but not A. ameiva), offered on a weekly basis, were used as a food source for tegus over a 10-month period. After 10 months, tegus were exposed to applicators containing control odors as well as those containing extracts from mice and lizards (A. ameiva). Mouse extracts elicited significantly higher TFAS as compared to those elicited by A. ameiva or control odors, suggesting that prey odors encountered in the environment shortly after hatching can influence prey preferences by these lizards later in life. These results also indicate that tegu lizards can learn to use specific odor cues associated with naturally occurring prey as releasers for subsequent hunting behaviors.

  3. Forgotten records of Chrysopelea taprobanica Smith, 1943 (Squamata: Colubridae) from India.

    PubMed

    Somaweera, Ruchira; Pantoja, Davi Lima; Deepak, V

    2015-04-17

    The colubrid snake Chrysopelea taprobanica Smith, 1943 was described from a holotype from Kanthali (= Kantalai) and paratypes from Kurunegala, both localities in Sri Lanka (formerly Ceylon) (Smith 1943). Since its description, literature pertaining to Sri Lankan snake fauna considered this taxon to be endemic to the island (Taylor 1950, Deraniyagala 1955, de Silva 1980, de Silva 1990, Somaweera 2004, Somaweera 2006, de Silva 2009, Pyron et al. 2013). In addition, earlier efforts on the Indian peninsula (e.g. Das 1994, 1997, Das 2003, Whitaker & Captain 2004, Aengals et al. 2012) and global data compilations (e.g. Wallach et al. 2014, Uetz & Hošek 2015) did not identify any record from mainland India until Guptha et al. (2015) recorded a specimen (voucher BLT 076 housed at Bio-Lab of Seshachalam Hills, Tirupathi, India) in the dry deciduous forest of Chamala, Seshachalam Biosphere Reserve in Andhra Pradesh, India in November 2013. Guptha et al. (2015) further mentioned an individual previously photographed in 2000 at Rishi Valley, Andhra Pradesh, but with no voucher specimen collected. Guptha's record, assumed to be the first confirmed record of C. taprobanica in India, is noteworthy as it results in a large range extension, from northern Sri Lanka to eastern India with an Euclidean distance of over 400 km, as well as a change of status, i.e., species not endemic to Sri Lanka. However, at least three little-known previous records of this species from India evaded most literature and were overlooked by the researchers including ourselves.

  4. A taxonomic revision of the Phrynosoma douglasii species complex (Squamata: Phrynosomatidae).

    PubMed

    Montanucci, Richard R

    2015-09-11

    Short-horned lizards (Phrynosoma douglasii species complex) occur throughout the inter-montane West and Great Plains of western North America. The comparative morphology and color pattern variation of short-horned lizards was studied in 3,174 specimens. Multivariate analyses of 20 morphological and color-pattern characters were applied to 977 specimens, and univariate statistics were summarized for 52 samples totaling 1,134 specimens. The results of the morphological data analyses support the recognition of P. douglasii (Bell 1828) as a distinct species, and the resurrection of P. brevirostris Girard 1858a and P. ornatissimum Girard 1858a as species distinct from P. hernandesi Girard 1858a. Two new species allied to P. brevirostris are described: P. bauri sp. nov. from the eastern plains of Colorado and northeastern New Mexico, southeastern Wyoming and southwestern Nebraska south of the North Platte River, and P. diminutum sp. nov. endemic to the San Luis Valley of southern Colorado and northern New Mexico. The Mexican taxon brachycercum Smith 1942 is reassigned as a subspecies of P. ornatissimum, based on non-discrete character differences and overall morphometric similarity. The ranges of P. hernandesi and P. ornatissimum broadly overlap in central New Mexico, the former taxon occupying the coniferous forests of disjunct mountain ranges, the latter occuring in the surrounding desert grasslands. Principal components analysis has revealed morphological evidence of hybridization where the two taxa meet, generally within ecotones between montane forest associations and grasslands. Principal components analysis has also revealed a high level of morphological variability in populations occurring in the Colorado Plateau region of northeastern Arizona, northwestern New Mexico, extreme southwestern Colorado and adjacent Utah. The evidence suggests that these populations arose through past hybridization between the two species. The taxon ornatum Girard 1858b, although sharing several traits with P. brevirostris, is morphologically close to P. hernandesi. It is regarded as a stabilized population of hybrid origin, but treated taxonomically as a subspecies of P. hernandesi. The taxonomic arrangement in this study, with the exception of P. douglasii, is largely discordant with the proposed taxonomy from a previously published study based on mitochondrial DNA sequence data.

  5. A new species of spectacularly coloured flat lizard Platysaurus (Squamata: Cordylidae: Platysaurinae) from southern Africa.

    PubMed

    Whiting, Martin J; Branch, William R; Pepper, Mitzy; Keogh, J Scott

    2015-07-16

    We describe a new species of flat lizard (Platysaurus attenboroughi sp. nov.) from the Richtersveld of the Northern Cape Province of South Africa and the Fish River Canyon region of southern Namibia. This species was formerly confused with P. capensis from the Kamiesberg region of Namaqualand, South Africa. Genetic analysis based on one mtDNA and two nDNA loci found Platysaurus attenboroughi sp. nov. to be genetically divergent from P. capensis and these species can also be differentiated by a number of scalation characters, coloration and their allopatric distributions. To stabilize the taxonomy the type locality of Platysaurus capensis A. Smith 1844 is restricted to the Kamiesberg region, Namaqualand, Northern Cape Province, South Africa.

  6. Seasonal spermatogenesis in the Mexican endemic oviparous lizard, Sceloporus aeneus (Squamata: Phrynosomatidae)

    PubMed Central

    Hernández-Gallegos, Oswaldo; Méndez-de la Cruz, Fausto Roberto; Villagrán-SantaCruz, Maricela; Rheubert, Justin L; Granados-González, Gisela; Gribbins, Kevin M

    2014-01-01

    Oviparous species of Sceloporus exhibit either seasonal or continuous spermatogenesis and populations from high-elevation show a seasonal pattern known as spring reproductive activity. We studied the spermatogenic cycle of a high-elevation (2700 m) population of endemic oviparous lizard, Sceloporus aeneus, that resided south of México, D.F. Histological analyses were performed on the testes and reproductive ducts from individual lizards collected monthly. This population of S. aeneus showed a seasonal pattern of spermatogenesis, with 4 successive phases common in other lizards. These include: 1) Quiescence in August, which contained solely spermatogonia and Sertoli cells; 2) Testicular recrudescence (September-January) when testes became active with mitotic spermatogonia, spermatocytes beginning meiosis, and the early stages of spermiogenesis with spermatids; 3) Maximum testicular activity occurred from March to May and is when the largest spermiation events ensued within the germinal epithelia, which were also dominated by spermatids and spermiogenic cells; 4) Testicular regression in June was marked with the number of all germs cells decreasing rapidly and spermatogonia dominated the seminiferous epithelium. February was a transitional month between recrudescence and maximum activity. The highest sperm abundance in the lumina of epididymides was during maximum testicular activity (March-May). Thus, before and after these months fewer spermatozoa were detected within the excurrent ducts as the testis transitions from recrudescence to maximum activity in February and from maximum activity to quiescence in June. Maximum spermatogenic activity corresponds with warmest temperatures at this study site. This pattern known as spring reproductive activity with a fall recrudescence was similar to other oviparous species of genus Sceloporus. PMID:26413407

  7. Temporal overlap of humans and giant lizards (Varanidae; Squamata) in Pleistocene Australia

    NASA Astrophysics Data System (ADS)

    Price, Gilbert J.; Louys, Julien; Cramb, Jonathan; Feng, Yue-xing; Zhao, Jian-xin; Hocknull, Scott A.; Webb, Gregory E.; Nguyen, Ai Duc; Joannes-Boyau, Renaud

    2015-10-01

    An obvious but key prerequisite to testing hypotheses concerning the role of humans in the extinction of late Quaternary 'megafauna' is demonstrating that humans and the extinct taxa overlapped, both temporally and spatially. In many regions, a paucity of reliably dated fossil occurrences of megafauna makes it challenging, if not impossible, to test many of the leading extinction hypotheses. The giant monitor lizards of Australia are a case in point. Despite commonly being argued to have suffered extinction at the hands of the first human colonisers (who arrived by 50 ka), it has never been reliably demonstrated that giant monitors and humans temporally overlapped in Australia. Here we present the results of an integrated U-Th and 14C dating study of a late Pleistocene fossil deposit that has yielded the youngest dated remains of giant monitor lizards in Australia. The site, Colosseum Chamber, is a cave deposit in the Mt Etna region, central eastern Australia. Sixteen new dates were generated and demonstrate that the bulk of the material in the deposit accumulated since ca. 50 ka. The new monitor fossil is, minimally, 30 ky younger than the previous youngest reliably dated record for giant lizards in Australia and for the first time, demonstrates that on a continental scale, humans and giant lizards overlapped in time. The new record brings the existing geochronological dataset for Australian giant monitor lizards to seven dated occurrences. With such sparse data, we are hesitant to argue that our new date represents the time of their extinction from the continent. Rather, we suspect that future fossil collecting will yield new samples both older and younger than 50 ka. Nevertheless, we unequivocally demonstrate that humans and giant monitor lizards overlapped temporally in Australia, and thus, humans can only now be considered potential drivers for their extinction.

  8. The fourth Bent-toed Gecko of the genus Cyrtodactylus (Squamata: Gekkonidae) from Java, Indonesia.

    PubMed

    Riyanto, Awal; Grismer, L Lee; Wood, Perry L

    2015-12-22

    Cyrtodactylus petani sp. nov. is a new species of Bent-toed Gecko from Java, Indonesia that had been masquerading under the name C. fumosus (Müller, 1895). The new species is differentiated from C. fumosus and all its Sundaland congeners by having the following combination of morphological characters: a maximum SVL of 57.2 mm; nine or ten supralabials; seven or eight infralabials; strongly tuberculate body and limbs; 20-25 paravertebral tubercles; 30-35 ventral scales; enlarged precloacal scales; enlarged femoral scales; 17-18 subdigital lamellae on the fourth toe; 31-35 continuous precloacal and femoral pores in males, pores absent in females; no precloacal groove; no enlarged median subcaudals; tubercles on anterior portion of tail; no reticulated pattern on top of head; a blotched dorsal pattern; and no paired, dark, semi-lunar shaped blotches on the nape.

  9. The Development of the Skull of the Egyptian Cobra Naja h. haje (Squamata: Serpentes: Elapidae)

    PubMed Central

    Khannoon, Eraqi R.; Evans, Susan E.

    2015-01-01

    Background The study of craniofacial development is important in understanding the ontogenetic processes behind morphological diversity. A complete morphological description of the embryonic skull development of the Egyptian cobra, Naja h. haje, is lacking and there has been little comparative discussion of skull development either among elapid snakes or between them and other snakes. Methodology/Principal Findings We present a description of skull development through a full sequence of developmental stages of the Egyptian cobra, and compare it to other snakes. Associated soft tissues of the head are noted where relevant. The first visible ossification centres are in the supratemporal, prearticular and surangular, with slight ossification visible in parts of the maxilla, prefrontal, and dentary. Epiotic centres of ossification are present in the supraoccipital, and the body of the supraoccipital forms from the tectum posterior not the tectum synoticum. The venom glands are visible as distinct bodies as early at stage 5 and enlarge later to extend from the otic capsule to the maxilla level with the anterior margin of the eye. The gland becomes more prominent shortly before hatching, concomitant with the development of the fangs. The tongue shows incipient forking at stage 5, and becomes fully bifid at stage 6. Conclusions/Significance We present the first detailed staging series of cranial development for the Egyptian cobra, Naja h. haje. This is one of the first studies since the classical works of G. de Beer and W. Parker that provides a detailed description of cranial development in an advanced snake species. It allows us to correct errors and misinterpretations in previous accounts which were based on a small sample of specimens of uncertain age. Our results highlight potentially significant variation in supraoccipital formation among squamates and the need for further research in this area. PMID:25860015

  10. The ultrastructure of spermatid development during spermiogenesis within the rosebelly lizard, Sceloporus variabilis (Reptilia, Squamata, Phrynosomatidae).

    PubMed

    Gribbins, Kevin M; Matchett, Caroline L; DelBello, Kathryn A; Rheubert, Justin; Villagrán-SantaCruz, Maricela; Granados-González, Gisela; Hernández-Gallegos, Oswaldo

    2014-03-01

    Several recent studies have mapped out the characters of spermiogenesis within several species of squamates. Many of these data have shown both conserved and possibly apomorphic morphological traits that could be important in future phylogenetic analysis within Reptilia. There, however, has not been a recent study that compares spermiogenesis and its similarities or differences between two species of reptile that reside in the same genus. Thus, the present analysis details the changes to spermiogenesis in Sceloporus variabilis and then compares spermatid morphologies to that of Sceloporus bicanthalis. Many of the morphological changes that the spermatids undergo in these two species are similar or conserved, which is similar to what has been reported in other squamates. There are six main character differences that can be observed during the development of the spermatids between these two sceloporid lizards. They include the presence (S. variabilis) or absence (S. bicanthalis) of a mitochondrial/endoplasmic reticulum complex near the Golgi apparatus during acrosome development, a shallow (S. variabilis) or deep (S. bicanthalis) nuclear indentation that accommodates the acrosomal vesicle, filamentous (S. variabilis) or granular (S. bicanthalis) chromatin condensation, no spiraling (S. variabilis) or spiraling (S. bicanthalis) of chromatin during condensation, absence (S. variabilis) or presence (S. bicanthalis) of the longitudinal manchette microtubules, and the lack of (S. variabilis) or presence (S. bicanthalis) of nuclear lacunae. This is the first study that compares spermiogenic ultrastructural characters between species within the same genus. The significance of the six character differences between two distantly related species within Sceloporus is still unknown, but these data do suggest that spermiogenesis might be a good model to study the hypothesis that spermatid ontogeny is species specific.

  11. Ultrastructural analysis of spermiogenesis in the Eastern Fence Lizard, Sceloporus undulatus (Squamata: Phrynosomatidae).

    PubMed

    Rheubert, Justin L; Sever, David M; Siegel, Dustin S; Gribbins, Kevin M

    2016-02-01

    Studies on reptilian sperm morphology have shown that variation exists at various taxonomic levels but studies on the ontogeny of variation are rare. Sperm development follows a generalized bauplan that includes acrosome development, nuclear condensation and elongation, and flagellar development. However, minute differences can be observed such as the presence/absence of manchette microtubules, structural organization during nuclear condensation, and presence/absence of a nuclear lacuna. The purpose of this investigation was to examine sperm development within the Sceloporus genus. The process begins with the development of an acrosomal complex from Golgi vesicles followed by nuclear condensation and elongation, which results in the presence of a nuclear lacuna. As the acrosomal complex differentiates, flagellar development commences with elongation of the distal centriole. Spermatid development culminates in a mature spermatid with a highly differentiated acrosomal complex, a condensed nucleus with a nuclear lacuna, and a differentiated flagellum. Although the overall developmental pattern is consistent with other squamate species, minute differences are observed, even within the same genus. For example there is variation in the presence/absence of an endoplasmic reticulum complex during acrosome development, presence/absence of a nuclear lacuna, and presence/absence of manchette microtubules within the three species of Sceloporus studied to date. Future studies concerning sperm morphology in closely related species will aid in our understanding of variation in sperm development and may prove to be useful in testing phylogenetic and evolutionary hypotheses.

  12. Ultrastructure of spermiogenesis in the Cottonmouth, Agkistrodon piscivorus (Squamata: Viperidae: Crotalinae).

    PubMed

    Gribbins, Kevin M; Rheubert, Justin L; Anzalone, Marla L; Siegel, Dustin S; Sever, David M

    2010-03-01

    To date multiple studies exist that examine the morphology of spermatozoa. However, there are limited numbers of data detailing the ontogenic characters of spermiogenesis within squamates. Testicular tissues were collected from Cottonmouths (Agkistrodon piscivorus) and tissues from spermiogenically active months were analyzed ultrastructurally to detail the cellular changes that occur during spermiogenesis. The major events of spermiogenesis (acrosome formation, nuclear elongation/DNA condensation, and flagellar development) resemble that of other squamates; however, specific ultrastructural differences can be observed between Cottonmouths and other squamates studied to date. During acrosome formation vesicles from the Golgi apparatus fuse at the apical surface of the nuclear membrane prior to making nuclear contact. At this stage, the acrosome granule can be observed in a centralized location within the vesicle. As elongation commences the acrosome complex becomes highly compartmentalized and migrates laterally along the nucleus. Parallel and circum-cylindrical microtubules (components of the manchette) are observed with parallel microtubules outnumbering the circum-cylindrical microtubules. Flagella, displaying the conserved 9 + 2 microtubule arrangement, sit in nuclear fossae that have electron lucent shoulders juxtaposed on either side of the spermatids basal plates. This study aims to provide developmental characters for squamates in the subfamily Crotalinae, family Viperidae, which may be useful for histopathological studies on spermatogenesis in semi-aquatic species exposed to pesticides. Furthermore, these data in the near future may provide morphological characters for spermiogenesis that can be added to morphological data matrices that may be used in phylogenetic analyses.

  13. Seasonal spermatogenic cycle and morphology of germ cells in the viviparous lizard Mabuya brachypoda (Squamata, Scincidae).

    PubMed

    Hernández-Franyutti, Arlette; Uribe, Mari Carmen

    2012-11-01

    We describe seasonal variations of the histology of the seminiferous tubules and efferent ducts of the tropical, viviparous skink, Mabuya brachypoda, throughout the year. The specimens were collected monthly, in Nacajuca, Tabasco state, Mexico. The results revealed strong annual variations in testicular volume, stages of the germ cells, and diameter and height of the epithelia of seminiferous tubules and efferent ducts. Recrudescence was detected from November to December, when initial mitotic activity of spermatogonia in the seminiferous tubules were observed, coinciding with the decrease of temperature, photoperiod and rainy season. From January to February, early spermatogenesis continued and early primary and secondary spermatocytes were developing within the seminiferous epithelium. From March through April, numerous spermatids in metamorphosis were observed. Spermiogenesis was completed from May through July, which coincided with an increase in temperature, photoperiod, and rainfall. Regression occurred from August through September when testicular volume and spermatogenic activity decreased. During this time, the seminiferous epithelium decreased in thickness, and germ cell recruitment ceased, only Sertoli cells and spermatogonia were present in the epithelium. Throughout testicular regression spermatocytes and spermatids disappeared and the presence of cellular debris, and scattered spermatozoa were observed in the lumen. The regressed testes presented the total suspension of spermatogenesis. During October, the seminiferous tubules contained only spermatogonia and Sertoli cells, and the size of the lumen was reduced, giving the appearance that it was occluded. In concert with testis development, the efferent ducts were packed with spermatozoa from May through August. The epididymis was devoid of spermatozoa by September. M. brachypoda exhibited a prenuptial pattern, in which spermatogenesis preceded the mating season. The seasonal cycle variations of spermatogenesis in M. brachypoda are the result of a single extended spermiation event, which is characteristic of reptilian species.

  14. Ultrastructural examination of spermiogenesis within the testis of the ground skink, Scincella laterale (Squamata, Sauria, Scincidae).

    PubMed

    Gribbins, Kevin M; Mills, Erin M; Sever, David M

    2007-02-01

    Although the events of spermiogenesis are commonly studied in amniotes, the amount of research available for lizards (Sauria) is lacking. Many studies have described the morphological characteristics of mature spermatozoa in lizards, but few detail the ultrastructural changes that occur during spermiogenesis. The purpose of this study was to gain a better understanding of the subcellular events of spermiogenesis within the temperate ground skink (Scincella laterale). The morphological data presented here represent the first complete ultrastructural study of spermiogenesis within the Scincidae clade. Samples of testes from 20 specimens were prepared using standard techniques for transmission electron microscopy. Many of the ultrastructural changes occurring during spermiogenesis within the ground skink are similar to that of other saurians. However, there were a few unique characteristics that to date have not been described during spermiogenesis in other lizards. For example, during early round spermatid development within the ground skink testis, proacrosomal granules begin to form within the acrosomal vesicle before making contact with the apex of the nucleus. Also, a prominent microtubular manchette develops during spermiogenesis; however, the circular component of the manchete is absent in this species of skink. This developmental difference in manchette formation may lead to the more robust and straight mature spermatozoa that are common within the Scincidae family. These anatomical character differences may be valuable nontraditional sources that along with more traditional sources (i.e., mitochondrial DNA) may help elucidate phylogenetic relationships, which are historically considered controversial at best, among species within Scincidae and Sauria.

  15. Temporal germ cell development strategy during continuous spermatogenesis within the montane lizard, Sceloporus bicanthalis (Squamata; Phrynosomatidae).

    PubMed

    Gribbins, Kevin; Anzalone, Marla; Collier, Matthew; Granados-González, Gisela; Villagrán-Santa Cruz, Maricela; Hernández-Gallegos, Oswaldo

    2011-10-01

    Sceloporus bicanthalis is a viviparous lizard that lives at higher elevations in Mexico. Adult male S. bicanthalis were collected (n = 36) from the Nevado de Toluca, Mexico (elevation is 4200 m) during August to December, 2007 and January to July, 2008. Testes were extracted, fixed in Trumps, and dehydrated in a graded series of ethanol. Tissues were embedded, sectioned (2 μm), stained, and examined via a light microscope to determine the spermatogenic developmental strategy of S. bicanthalis. In all months examined, the testes were spermiogenically active; based on this, plus the presence of sperm in the lumina of seminiferous tubules, we inferred that S. bicanthalis had year-round or continuous spermatogenesis, unlike most reptiles that occupy a temperate or montane habitat. It was recently reported that seasonally breeding reptiles had a temporal germ cell development strategy similar to amphibians, where germ cells progress through spermatogenesis as a single population, which leads to a single spermiation event. This was much different than spatial development within the testis of other derived amniotes. We hypothesized that germ cell development was temporal in S. bicanthalis. Therefore, we wanted to determine whether reptiles that practice continuous spermatogenesis have a mammalian-like spatial germ cell development, which is different than the typical temperate reptile exhibiting a temporal development. In the present study, S. bicanthalis had a temporal development strategy, despite its continuous spermatogenic cycle, making them similar to tropical anoles.

  16. Ultrastructural description of spermiogenesis within the Mediterranean Gecko, Hemidactylus turcicus (Squamata: Gekkonidae).

    PubMed

    Rheubert, Justin L; Siegel, Dustin S; Venable, Katherine J; Sever, David M; Gribbins, Kevin M

    2011-10-01

    We studied spermiogenesis in the Mediterranean Gecko, Hemidactylus turcicus, at the electron microscope level and compared to what is known within other Lepidosaurs. In H. turcicus germ cells are connected via cytoplasmic bridges where organelle and cytoplasm sharing is observed. The acrosome develops from merging transport vesicles that arise from the Golgi and subsequently partition into an acrosomal cap containing an acrosomal cortex, acrosomal medulla, perforatorium, and subacrosomal cone. Condensation of DNA occurs in a spiral fashion and elongation is aided by microtubules of the manchette. A nuclear rostrum extends into the subacrosomal cone and is capped by an epinuclear lucent zone. Mitochondria and rough endoplasmic reticulum migrate to the posterior portion of the developing germ cell during the cytoplasmic shift and the flagellum elongates. Mitochondria surround the midpiece as the anlage of the annulus forms. The fibrous sheath begins at mitochondrial tier 3 and continues into the principal piece. Peripheral fibers associated with microtubule doublets 3 and 8 are grossly enlarged. During the final stages of germ cell development spermatids are wrapped with a series of Sertoli cell processes, which exhibit ectoplasmic specializations and differing cytoplasmic consistencies. The results observed here corroborate previous studies, which show the conservative nature of sperm morphology. However, ultrastructural character combinations specific to sperm and spermiogenesis seem to differ among taxa. Further studies into sperm morphology are needed in order to judge the relevance of the ontogenic changes recorded here and to determine their role in future studies on amniote evolution.

  17. Renal sexual segment of the ground skink, Scincella laterale (Reptilia, Squamata, Scincidae).

    PubMed

    Sever, David M; Hopkins, William A

    2005-10-01

    Mature squamates possess hypertrophied regions of the distal urinary ducts, the renal sexual segment (RSS). The RSS is believed to provide seminal fluid that mixes with sperm and is released into the female cloaca during coitus. This study is the first to describe ultrastructure of the RSS in a lizard collected throughout the active season. The species examined, Scincella laterale, represents the largest family (Scincidae: 1,200 species) of lizards. Although sperm are present in the posterior ductus deferens of male S. laterale throughout the year, an annual spermatogenic cycle occurs that results in spermiation in spring, coinciding with maximum development of the RSS. Female S. laterale may possess stored sperm in vaginal crypts from March-May and large oviductal eggs April-June. Thus, the correlation between mating and RSS activity observed in other squamates is also found in S. laterale. Cytologically, the active RSS consists of columnar cells with numerous apical, electron-dense secretory vacuoles which are released by an apocrine process. The granules stain positively for proteins with bromphenol blue and react with PAS for neutral carbohydrates. After the mating season the RSS undergoes recrudescence and the electron-dense granules are replaced by a mucoid secretion that characterizes more proximal portions of the nephric tubules throughout the year. Little variation in ultrastructure of the RSS occurs between S. laterale and Cnemidophorus lemniscatus (Teiidae), the only other lizard in which seasonal variation of the RSS has been studied using similar methods. Females exhibit differentiation similar to that of males in the distal urinary tubules, but to a lesser degree. This is only the second such report for female squamates, and the differentiation of the region in females is proposed to result from adrenal androgens.

  18. The complete mitochondrial genome of Chinese glass lizard Ophisaurus harti (Squamata: Anguidae).

    PubMed

    Pan, Hong-Chun; Liu, Lei; Li, Ping; Li, Xiao-Fei; Liu, Zheng-Liang

    2015-04-01

    The complete mitochondrial genome of Ophisaurus harti is a circular molecule of 17,163 bp in length, containing 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs and a control region. The A + T content of the overall base composition of H-strand is 54.9% (T: 23.4%; C: 30.8%; A: 31.5%; G: 14.3%). COI gene begins with GTG as start codon, while other 12 protein-coding genes start with a typical ATG initiation codon. ND1. COI. ATP8. ATP6. ND4L and ND5 genes are terminated with TAA as stop codon, ND2. ND6 and Cyt b end with TAG, COIII ends with TA, COII and ND3 end with T and ND4 ends with TG.

  19. Integrative analyses of speciation and divergence in Psammodromus hispanicus (Squamata: Lacertidae)

    PubMed Central

    2011-01-01

    Background Genetic, phenotypic and ecological divergence within a lineage is the result of past and ongoing evolutionary processes, which lead ultimately to diversification and speciation. Integrative analyses allow linking diversification to geological, climatic, and ecological events, and thus disentangling the relative importance of different evolutionary drivers in generating and maintaining current species richness. Results Here, we use phylogenetic, phenotypic, geographic, and environmental data to investigate diversification in the Spanish sand racer (Psammodromus hispanicus). Phylogenetic, molecular clock dating, and phenotypic analyses show that P. hispanicus consists of three lineages. One lineage from Western Spain diverged 8.3 (2.9-14.7) Mya from the ancestor of Psammodromus hispanicus edwardsianus and P. hispanicus hispanicus Central lineage. The latter diverged 4.8 (1.5-8.7) Mya. Molecular clock dating, together with population genetic analyses, indicate that the three lineages experienced northward range expansions from southern Iberian refugia during Pleistocene glacial periods. Ecological niche modelling shows that suitable habitat of the Western lineage and P. h. edwardsianus overlap over vast areas, but that a barrier may hinder dispersal and genetic mixing of populations of both lineages. P. h. hispanicus Central lineage inhabits an ecological niche that overlaps marginally with the other two lineages. Conclusions Our results provide evidence for divergence in allopatry and niche conservatism between the Western lineage and the ancestor of P. h. edwardsianus and P. h. hispanicus Central lineage, whereas they suggest that niche divergence is involved in the origin of the latter two lineages. Both processes were temporally separated and may be responsible for the here documented genetic and phenotypic diversity of P. hispanicus. The temporal pattern is in line with those proposed for other animal lineages. It suggests that geographic isolation and vicariance played an important role in the early diversification of the group, and that lineage diversification was further amplified through ecological divergence. PMID:22129245

  20. Phylogeny and biogeography of the most diverse clade of South American gymnophthalmid lizards (Squamata, Gymnophthalmidae, Cercosaurinae).

    PubMed

    Torres-Carvajal, Omar; Lobos, Simón E; Venegas, Pablo J; Chávez, Germán; Aguirre-Peñafiel, Vanessa; Zurita, Daniel; Echevarría, Lourdes Y

    2016-06-01

    Nearly 50% of the diversity of the speciose Neotropical lizard clade Gymnophthalmidae is nested within the subclade Cercosaurinae. The taxonomy of Cercosaurinae lizards has been historically confusing because many diagnostic characters of those clades traditionally ranked as genera do not represent true diagnostic apomorphies. Even though molecular phylogenies of several 'genera' have been presented in the last few years, some of them remain poorly sampled (e.g., Anadia, Echinosaura, Potamites, Riama). In this paper we present a more comprehensive phylogeny of Cercosaurinae lizards with emphasis on Andean taxa from Ecuador and Peru, as well as a time-calibrated phylogeny with reconstruction of ancestral areas. Our analysis includes 52% of all recognized species of Cercosaurinae (67 species) and 1914 characters including three mitochondrial and one nuclear gene. We find that Anadia, Echinosaura, Euspondylus, Potamites, Proctoporus, and Riama are not monophyletic: the Tepuian Anadia mcdiarmidi is not sister to Andean species of Anadia; Echinosaura sulcarostrum is not included in the same clade formed by other species of Echinosaura and their more recent common ancestor; Teuchocercus is nested within Echinosaura; species of Euspondylus included in this study are nested within Proctoporus; Riama laudahnae is included in Proctoporus; and Potamites is paraphyletic and split in two separate clades, one of which we name Gelanesaurus, also a new genus-group name. Within Potamites, P. ecpleopus is paraphyletic, and P. strangulatus strangulatus and P. strangulatus trachodus are recognized as two distinct species. We also identify three unnamed clades (i.e., not nested within any of the recognized 'genera') from Andean populations in Ecuador and Peru. The estimated age of the clade Cercosaurinae (∼60Ma) corresponds to the early stages of the northern Andes. Even though the distribution of the most recent common ancestor of Cercosaurinae remains equivocal, our analysis shows that these lizards colonized and radiated along the northern Andes before reaching the central Andes in Peru. Finally, we present phylogenetic definitions for some of the recovered clades to promote a clear and precise classification of Cercosaurinae lizards.

  1. A new species of arboreal iguanid lizard, genus Stenocercus (Squamata: Iguania), from central Peru.

    PubMed

    Venegas, Pablo J; Duran, Vilma; Garcia-Burneo, Karla

    2013-01-30

    We describe a new species of Stenocercus from an interandean valley of the upper Río Huallaga on the Amazonian slope of central Peru (Región Huánuco), at an elevation of 1700-1900 m. The new species differs from other Stenocercus, except S. boettgeri, S. haenschi, S. humeralis, and S. varius, by the combination of the following characters: presence of granular scales on the posterior surface of the thighs, enlarged vertebrals, three caudal whorls per autotomic segment, a medially complete antegular fold, non-spinose caudals, and by males lacking a black transverse band on the ventral surface of the neck. However, the new Stenocercus differs from these, with the exception of S. humeralis, by having more scales around the midbody (104-107, =105.66) than S. boettgeri (79-104, Mean= 88.61), S. haenschi (57-64, Mean=60.50), and S. varius (74-88, Mean=82.35); and from S. humeralis by having the scales in the frontonasal region nearly equal in size to the scales in the occipitoparietal region, while in S. humeralis the scales on the frontonasal region are twice or three times longer than the scales on the occipitoparietal region.

  2. Helminths of the Lizard Salvator merianae (Squamata, Teiidae) in the Caatinga, Northeastern Brazil.

    PubMed

    Teixeira, A A M; Brito, S V; Teles, D A; Ribeiro, S C; Araujo-Filho, J A; Lima, V F; Pereira, A M A; Almeida, W O

    2016-08-29

    The lizard Salvator merianae is a widely distributed species in South America, occurring from southern Amazonia to the eastern Andes and northern Patagonia. Studies on the parasitic fauna of this lizard have revealed that it is a host for helminths in various Brazilian biomes. The present work provides new parasitological data on the gastrointestinal nematodes associated with the lizard S. merianae. Sixteen specimens were analyzed from nine different locations in a semi-arid region in northeastern Brazil. Five species of nematodes were identified. Oswaldofilaria petersi was first recorded as a parasite of the S. merianae, thus increasing the knowledge of the fauna of parasites that infect large Neotropical lizards.

  3. A nesting of vipers: Phylogeny and historical biogeography of the Viperidae (Squamata: Serpentes).

    PubMed

    Wüster, Wolfgang; Peppin, Lindsay; Pook, Catharine E; Walker, Daniel E

    2008-11-01

    Despite their medical interest, the phylogeny of the snake family Viperidae remains inadequately understood. Previous studies have generally focused either on the pitvipers (Crotalinae) or on the Old World vipers (Viperinae), but there has been no comprehensive molecular study of the Viperidae as a whole, leaving the affinities of key taxa unresolved. Here, we infer the phylogenetic relationships among the extant genera of the Viperidae from the sequences of four mitochondrial genes (cytochrome b, NADH subunit 4, 16S and 12S rRNA). The results confirm Azemiops as the sister group of the Crotalinae, whereas Causus is nested within the Viperinae, and thus not a basal viperid or viperine. Relationships among the major clades of Viperinae remain poorly resolved despite increased sequence information compared to previous studies. Bayesian molecular dating in conjunction with dispersal-vicariance analysis suggests an early Tertiary origin in Asia for the crown group Viperidae, and rejects suggestions of a relatively recent, early to mid-Tertiary origin of the Caenophidia.

  4. Elucidating the global elapid (Squamata) richness pattern under metabolic theory of ecology

    NASA Astrophysics Data System (ADS)

    Braga, Rosana Talita; Oliveira de Grande, Thallita; de Souza Barreto, Bruno; Felizola Diniz-Filho, José Alexandre; Terribile, Levi Carina

    2014-04-01

    Environmental determinants of global patterns in species richness are still uncertain. The Metabolic Theory of Ecology (MTE) proposes that species richness patterns can be explained by environmental temperature acting on the metabolism of ectothermic organisms. However, the generality of this theory has been questioned due to its low fit to the geographic variation in species richness of different taxonomic groups. Here, we investigated whether the MTE drives elapid richness, testing the non-stationarity of the relationship between the natural logarithm of species richness (ln S) and the inverse function of temperature (1/kT) using a geographically weighted regression (GWR). The relationship between ln S and 1/kT varied systematically over space and showed non-stationarity. Few tropical locations were consistent with MTE predictions, whereas other regions fitted differently. Although the slope of the GWR model ranged from low to high, the temperature did not predict species richness strongly on average and did not limit the upper values of richness. The response of richness to temperature in some areas might reflect a recent history of colonization and diversification of species across tropical and subtropical regions. In regions not affected by temperature, species richness should be structured by other biotic and abiotic interactions. This scenario reveals that the non-stationarity of the relationship would be linked to idiosyncrasies in the sample sites, which can drift the magnitude or change the relationship between species richness and temperature throughout space.

  5. A new species of Cyrtodactylus (Squamata: Gekkonidae) from Ninh Binh Province, Vietnam.

    PubMed

    Le, Dzung Trung; Nguyen, Truong Quang; Le, Minh Duc; Ziegler, Thomas

    2016-09-09

    We describe a new species of the genus Cyrtodactylus on the basis of six specimens collected from the limestone forest of the Van Long Wetland Nature Reserve, Ninh Binh Province, Vietnam. Cyrtodactylus soni sp. nov. can be distinguished from its congeners by genetic distinction and morphological differences in number of femoral and precloacal pores, femoral scales, ventral scales, lamellae, subcaudals, and dorsal tubercle arrangement, as well as in size and color pattern. In the phylogenetic analyses, the new species is nested in a clade containing taxa from northwestern and northcentral Vietnam and northern Laos.

  6. Redescription Cyrtodactylus lateralis (Werner) (Squamata: Gekkonidae) and Phylogeny of the Prehensile-tailed Cyrtodactylus.

    PubMed

    Harvey, Michael B; O'connell, Kyle A; Wostl, Elijah; Riyanto, Awal; Kurniawan, Nia; Smith, Eric N; Grismer, L Lee

    2016-05-04

    We redescribe Cyrtodactylus lateralis (Werner) on the basis of new specimens. Cyrtodactylus lateralis is a prehensile-tailed species, known from scattered lowland to mid-elevation localities in northern Sumatra. The prehensile-tailed Cyrtodactylus are more speciose and have a wider distribution than previously thought. This group includes a mainland SE Asian clade consisting of C. elok, C. interdigitalis, and C. brevipalmatus and an insular clade containing C. durio, C. lateralis, C. nuaulu, C. serratus, C. spinosus, and C. stresemanni. However, a distinctive color pattern in the Wallacean and Papuan species and uncertainty surrounding the type locality of C. stresemanni raise unresolved questions about the inclusiveness of the insular clade. DNA sequence data supports a close relationship between C. elok and C. interdigitalis, but also reveals that C. lateralis and C. durio are not closely related to these species.

  7. A revised key to the lizards of Iran (Reptilia: Squamata: Lacertilia).

    PubMed

    Nasrabadi, Reza; Rastegar-Pouyani, Nasrullah; Rastegar-Pouyani, Eskandar; Gharzi, Ahmad

    2017-02-03

    During recent years several lizard taxa have been added to the faunal list of Iran. Descriptions and new records are scattered in different publications in the herpetological literature. We here present species accounts for 152 species belonging to 43 genera and 10 families up to July 2016. The most diverse family is Lacertidae with 9 genera, 49 species and 2 subspecies, followed by Gekkonidae with 13 genera and 43 species, Agamidae with 5 genera, 18 species and 4 subspecies, Scincidae with 7 genera, 18 species and 2 subspecies, Phyllodactylidae with 1 genus and 10 species, Sphaerodactylidae with 2 genera and 4 species, Varanidae with 1 genus, 3 species and 2 subspecies, Uromastycidae with 2 genera and 3 species, Eublepharidae with 1 genus and 3 species, and Anguidae with 2 genera and 2 species. The current paper provides a dichotomous key including all of the currently recognized lizards of Iran.

  8. Morphological and molecular identification of ticks infesting Boa constrictor (Squamata, Boidae) in Manaus (Central Brazilian Amazon).

    PubMed

    Fiorini, Leonardo Costa; Craveiro, Adriana Bentes; Mendes, Márcia Cristina; Chiesorin Neto, Laerzio; Silveira, Ronis Da

    2014-01-01

    The Boa constrictor is one of the world's largest vertebrate carnivores and is often found in urban areas in the city of Manaus, Brazil. The morphological identification of ticks collected from 27 snakes indicated the occurrence of Amblyomma dissimile Koch 1844 on all individuals sampled. In contrast, Amblyomma rotundatum Koch was found on only two snakes. An analysis of the 16S rRNA molecular marker confirmed the morphological identification of these ectoparasites.

  9. Material properties of the skin of the Kenyan sand boa Gongylophis colubrinus (Squamata, Boidae).

    PubMed

    Klein, Marie-Christin G; Deuschle, Julia K; Gorb, Stanislav N

    2010-09-01

    On the basis of structural data, it has been previously assumed that the integument of snakes consists of a hard, robust, inflexible outer surface (Oberhäutchen and beta-layer) and soft, flexible inner layers (alpha-layers). The aim of this study was to compare material properties of the outer and inner scale layers of the exuvium of Gongylophis colubrinus, to relate the structure of the snake integument to its mechanical properties. The nanoindentation experiments have demonstrated that the outer scale layers are harder, and have a higher effective elastic modulus than the inner scale layers. The results obtained provide strong evidence about the presence of a gradient in the material properties of the snake integument. The possible functional significance of this gradient is discussed here as a feature minimizing damage to the integument during sliding locomotion on an abrasive surface, such as sand.

  10. Distinct Patterns of Desynchronized Limb Regression in Malagasy Scincine Lizards (Squamata, Scincidae)

    PubMed Central

    Miralles, Aurélien; Hipsley, Christy A.; Erens, Jesse; Gehara, Marcelo; Rakotoarison, Andolalao; Glaw, Frank; Müller, Johannes; Vences, Miguel

    2015-01-01

    Scincine lizards in Madagascar form an endemic clade of about 60 species exhibiting a variety of ecomorphological adaptations. Several subclades have adapted to burrowing and convergently regressed their limbs and eyes, resulting in a variety of partial and completely limbless morphologies among extant taxa. However, patterns of limb regression in these taxa have not been studied in detail. Here we fill this gap in knowledge by providing a phylogenetic analysis of DNA sequences of three mitochondrial and four nuclear gene fragments in an extended sampling of Malagasy skinks, and microtomographic analyses of osteology of various burrowing taxa adapted to sand substrate. Based on our data we propose to (i) consider Sirenoscincus Sakata & Hikida, 2003, as junior synonym of Voeltzkowia Boettger, 1893; (ii) resurrect the genus name Grandidierina Mocquard, 1894, for four species previously included in Voeltzkowia; and (iii) consider Androngo Brygoo, 1982, as junior synonym of Pygomeles Grandidier, 1867. By supporting the clade consisting of the limbless Voeltzkowia mira and the forelimb-only taxa V. mobydick and V. yamagishii, our data indicate that full regression of limbs and eyes occurred in parallel twice in the genus Voeltzkowia (as hitherto defined) that we consider as a sand-swimming ecomorph: in the Voeltzkowia clade sensu stricto the regression first affected the hindlimbs and subsequently the forelimbs, whereas the Grandidierina clade first regressed the forelimbs and subsequently the hindlimbs following the pattern prevalent in squamates. Timetree reconstructions for the Malagasy Scincidae contain a substantial amount of uncertainty due to the absence of suitable primary fossil calibrations. However, our preliminary reconstructions suggest rapid limb regression in Malagasy scincids with an estimated maximal duration of 6 MYr for a complete regression in Paracontias, and 4 and 8 MYr respectively for complete regression of forelimbs in Grandidierina and hindlimbs in Voeltzkowia. PMID:26042667

  11. Philodryas chamissonis (Reptilia: Squamata: Colubridae) preys on the arboreal marsupial Dromiciops gliroides (Mammalia: Microbiotheria: Microbiotheriidae).

    PubMed

    Muñoz-Leal, S; Ardiles, K; Figueroa, R A; González-Acuña, D

    2013-02-01

    Philodryas chamissonis, the Chilean long-tailed snake, is a diurnal predator mainly of Liolaemus lizards, but also of amphibians, birds, rodents and juvenile rabbits. Dromiciops gliroides (Colocolo opossum) is an arboreal marsupial endemic of temperate rainforest of southern South America. Little information is available about this marsupial's biology and ecology. Here we report the predation of one Colocolo opossum by an adult female P. chamissonis in a mixed Nothofagus forest, composed mainly by N. dombeyi, N. glauca and N. alpina trees, in the "Huemules de Niblinto" National Reserve, Nevados de Chillán, Chile. Since these two species have different activity and habitat use patterns, we discuss how this encounter may have occurred. Although it could just have been an opportunistic event, this finding provides insights into the different components of food chains in forest ecosystems of Chile.

  12. Ultrastructure and wear patterns of the ventral epidermis of four snake species (Squamata, Serpentes).

    PubMed

    Klein, Marie-Christin G; Gorb, Stanislav N

    2014-10-01

    Snakes are limbless tetrapods highly specialized for sliding locomotion. This locomotion leads to the skin being exposed to friction loads, especially on the ventral body side, which leads to wear. It is presumed that snakes therefore have specific optimizations for minimizing abrasion. Scales from snakes with habitat, locomotor and/or behavior specializations have specific gradients in material properties that may be due to different epidermal architecture. To approach this issue we examined the skin of Lampropeltis getula californiae (terrestrial), Epicrates cenchria cenchria (generalist), Morelia viridis (arboreal), and Gongylophis colubrinus (burrowing) with a focus on (i) the ultrastructure of the ventral epidermis and (ii) the qualitative abrasion pattern of the ventral scales. Scanning and transmission electron microscopy revealed variations in the structure, thickness, layering, and material composition of the epidermis between the species. Furthermore, SEM and white light interferometer images of the scale surface showed that the abrasion patterns differed, even when the snakes were reared on the same substrate. These data support the idea that (i) a specific gradient in material properties may be due to a variation in epidermis architecture (thickness/ultrastructure) and (ii) this variation may be an optimization of material properties for specific ways of life.

  13. Mitochondrial DNA Variability within Uromastyx ornata philbyi (Agamidae: Squamata) from Southwestern Saudi Arabia

    PubMed Central

    Amer, Sayed A. M.; Ahmed, Mohamed M.; Wilms, Thomas M.; Shobrak, Mohammed; Kumazawa, Yoshinori

    2012-01-01

    Approximately 2.4 kbp of mitochondrial DNA was sequenced from 9 individuals of Uromastyx ornata philbyi originating from Taif, Namas, Al-Baha, and Jazan in southwestern Saudi Arabia. The sequenced regions cover eight tRNA genes (tRNAGln, tRNAIle, tRNAMet, tRNATrp, tRNAAla, tRNAAsn, tRNACys, and tRNATyr) and two protein-coding genes (NADH dehydrogenase subunit 2 and cytochrome b). U. ornata philbyi had an insertion of 170 bp length between tRNAGln and tRNAIle genes. The first 128 bp of this insertion was similar to the one identified earlier in U. ornata ornata and can be folded into a stem-and-loop structure, which was less stable in U. ornata philbyi than in U. ornata ornata, or the second tRNAGln gene. The next 42 bp of the insertion was unique in U. ornata philbyi and additionally retained a stable stem-and-loop structure. Most base substitutions found in the sequenced genes were synonymous transitions rather than transversions. Tree analyses supported the sister group relationship between the two U. ornata subspecies and divided U. ornata philbyi into two groups: Taif+Namas group in the east of Sarawat and Al-Baha+Jazan group in the west of Sarawat. These molecular data are in agreement with current classification of U. ornata. PMID:22312319

  14. Phylogeny, biogeography, and display evolution in the tree and brush lizard genus Urosaurus (Squamata: Phrynosomatidae).

    PubMed

    Feldman, Chris R; Flores-Villela, Oscar; Papenfuss, Theodore J

    2011-12-01

    The brush and tree lizards (Urosaurus) are a small clade of phrynosomatid lizards native to western North America. Though not as well known as their diverse sister clade, the spiny lizards (Sceloporus), some Urosaurus have nonetheless become model organisms in integrative biology. In particular, dramatic phenotypic and behavioral differences associated with specific mating strategies have been exploited to address a range of ecological and evolutionary questions. However, only two phylogenies have been proposed for the group, one of which is pre-cladistic and both based principally on morphological characters that might not provide robust support for relationships within the group. To help provide investigators working on Urosaurus with a robust phylogeny in which to frame ecological and evolutionary questions, we establish a molecular phylogeny for the group. We sampled three mitochondrial and three nuclear loci, and estimated phylogenetic relationships within Urosaurus using both maximum parsimony (MP) and Bayesian inference (BI), as well as a coalescent-based species tree approach. Finally, we used two methods of ancestral state reconstruction (ASR) to gain insight into the evolution of microhabitat preference and male display signals, traits that have been the focus of studies on Urosaurus. All reconstruction methods yield nearly the same ingroup topology that is concordant in most respects with the previous cladistic analysis of the group but with some significant differences; our data suggest the primary divergence in Urosaurus occurs between a clade endemic to the Pacific versant of Mexico and the lineages of Baja California and the southwestern US, rather than placing Urosaurus graciosus as the basal taxon and linking the Baja and Mexican endemics. We find support for a single transition to a saxicolous lifestyle within the group, and either the independent gain or loss of arboreality. The evolution of throat color patterns (i.e. dewlaps) appears complex, with multiple color morphs likely involving orange reconstructed as ancestral to the group and to most lineages, followed by a single transition to a fixed blue-throated morph in one clade. These results should provide a useful framework for additional comparative work with Urosaurus, and establish the phylogenetic context in which Urosaurus diversity arose.

  15. Phylogenetic relationships and limb loss in sub-Saharan African scincine lizards (Squamata: Scincidae).

    PubMed

    Whiting, Alison S; Bauer, Aaron M; Sites, Jack W

    2003-12-01

    Skinks are the largest family of lizards and are found worldwide in a diversity of habitats. One of the larger and more poorly studied groups of skinks includes members of the subfamily Scincinae distributed in sub-Saharan Africa. Sub-Saharan African scincines are one of the many groups of lizards that show limb reduction and loss, and the genus Scelotes offers an excellent opportunity to look at limb loss in a phylogenetic context. Phylogenetic relationships were reconstructed for a total of 52 taxa representing all subfamilies of skinks as well as other Autarchoglossan families using sequence from six gene regions including; 12S, 16S, and cytochrome b (mitochondrial), as well as alpha-Enolase, 18S, and C-mos (nuclear). The family Scincidae is recovered as monophyletic and is the sister taxon to a (Cordylidae+Xantusiidae) clade. Within skinks the subfamily Acontinae is monophyletic and sister group to all remaining skinks. There is no support for the monophyly of the subfamilies Lygosominae and Scincinae, but sub-Saharan African scincines+Feylinia form a well supported monophyletic group. The monophyly of Scelotes is confirmed, and support is found for two geographic groups within the genus. Reconstructions of ancestral states for limb and digital characters show limited support for the reversal or gain of both digits and limbs, but conservative interpretation of the results suggest that limb loss is common, occurring multiple times throughout evolutionary history, and is most likely not reversible.

  16. Morphology and development of the placentae in Eulamprus quoyii group skinks (Squamata: Scincidae)

    PubMed Central

    Murphy, Bridget F; Brandley, Matthew C; Murphy, Christopher R; Thompson, Michael B

    2012-01-01

    Frequent evolutionary changes in reproductive mode have produced a wide range of placental structures in viviparous squamate reptiles. Closely related species with different placental structures and resolved phylogenetic relationships are particularly useful for reconstructing how placentae might have transformed during the evolutionary process. We used light microscopy to study placental morphology in mid- to late stage embryos of four closely related species of Eulamprus, a genus of viviparous scincid lizards that we had reason to suspect may display significant interspecific variation in placental morphology. Embryos from all four species possess a chorioallantoic placenta, an omphaloplacenta and an interomphalopleuric membrane, characteristics present in other viviparous skinks. However, unlike other viviparous skinks but characteristic of oviparous skinks, the allantois expands to surround the yolk sac in each species, supplanting the omphalopleure with a larger area of chorioallantois until a chorioallantoic placenta surrounds the entire egg in one specimen that is only a few days from birth. All four Eulamprus species share the same extraembryonic membrane morphology, but the cellular morphology of the uterine epithelium in the chorioallantoic placenta and omphaloplacenta varies between species. We determined that the interomphalopleuric membrane is a shared derived character of the Eulamprus quoyii species group. New phylogenetic information indicates that variation in the chorioallantoic placenta is a result of two independent transitions, but that variation in the omphaloplacenta can be explained using a single change within the species studied. Our results indicate that E. quoyii group skinks are a valuable model for investigating the evolution of viviparity, as extraembryonic membrane development in these species shows features characteristic of both oviparous and viviparous skinks. PMID:22420511

  17. Two new species of the genus Goniurosaurus (Squamata: Sauria: Eublepharidae) from southern China.

    PubMed

    Yang, Jian-Huan; Chan, Bosco Pui-Lok

    2015-06-26

    Two new species of large geckos in the genus Goniurosaurus are described based on specimens collected from karst areas of Guangxi Zhuang Autonomous Region, southern China: Goniurosaurus kadoorieorum sp. nov. and Goniurosaurus kwangsiensis sp. nov. Data on natural history of the new species are provided, as well as discussions on the current conservation status of Goniurosaurus species in southern China. Due to the popularity of this genus as novelty pets, and recurring cases of scientific descriptions driving herpetofauna to near-extinction by commercial collectors, we do not disclose the collecting localities of these restricted-range species in this publication. However, such information has been presented to relevant government agencies, and is available upon request by fellow scientists.

  18. Sex chromosomes and karyotype of the (nearly) mythical creature, the Gila monster, Heloderma suspectum (Squamata: Helodermatidae).

    PubMed

    Johnson Pokorná, Martina; Rovatsos, Michail; Kratochvíl, Lukáš

    2014-01-01

    A wide variety of sex determination systems exist among squamate reptiles. They can therefore serve as an important model for studies of evolutionary transitions among particular sex determination systems. However, we still have only a limited knowledge of sex determination in certain important lineages of squamates. In this respect, one of the most understudied groups is the family Helodermatidae (Anguimorpha) encompassing the only two venomous species of lizards which are potentially lethal to human beings. We uncovered homomorphic ZZ/ZW sex chromosomes in the Gila monster (Heloderma suspectum) with a highly heterochromatic W chromosome. The sex chromosomes are morphologically similar to the ZZ/ZW sex chromosomes of monitor lizards (Varanidae). If the sex chromosomes of helodermatids and varanids are homologous, female heterogamety may be ancestral for the whole Anguimorpha group. Moreover, we found that the karyotype of the Gila monster consists of 2n = 36 chromosomes (14 larger metacentric chromosomes and 22 acrocentric microchromosomes). 2n = 36 is the widely distributed chromosomal number among squamates. In his pioneering works representing the only previous cytogenetic examination of the family Helodermatidae, Matthey reported the karyotype as 2n = 38 and suggested a different chromosomal morphology for this species. We believe that this was probably erroneously. We also discovered a strong accumulation of telomeric sequences on several pairs of microchromosomes in the Gila monster, which is a trait documented relatively rarely in vertebrates. These new data fill an important gap in our understanding of the sex determination and karyotype evolution of squamates.

  19. Differentiation of Sex Chromosomes and Karyotype Characterisation in the Dragonsnake Xenodermus javanicus (Squamata: Xenodermatidae).

    PubMed

    Rovatsos, Michail; Johnson Pokorná, Martina; Kratochvíl, Lukáš

    2015-01-01

    Highly differentiated heteromorphic ZZ/ZW sex chromosomes with a heterochromatic W are a basic principle among advanced snakes of the lineage Colubroidea, while other snake lineages generally lack these characteristics. For the first time, we cytogenetically examined the dragonsnake, Xenodermus javanicus, a member of the family Xenodermatidae, which is phylogenetically nested between snake lineages with and without differentiated sex chromosomes. Although most snakes have a karyotype with a stable chromosomal number of 2n = 36, the dragonsnake has an unusual, derived karyotype with 2n = 32 chromosomes. We found that heteromorphic ZZ/ZW sex chromosomes with a heterochromatic W are present in the dragonsnake, which suggests that the emergence of a highly differentiated W sex chromosome within snakes predates the split of Xenodermatidae and the clade including families Pareatidae, Viperidae, Homalopsidae, Lamprophiidae, Elapidae, and Colubridae. Although accumulations of interstitial telomeric sequences have not been previously reported in snakes, by using FISH with a telomeric probe we discovered them in 6 pairs of autosomes as well as in the W sex chromosome of the dragonsnake. Similarly to advanced snakes, the sex chromosomes of the dragonsnake have a significant accumulation of repeats containing a (GATA)n sequence. The results facilitate the dating of the differentiation of sex chromosomes within snakes back to the split between Xenodermatidae and other advanced snakes, i.e. around 40-75 mya.

  20. Embryonic development of the skull of the Andean lizard Ptychoglossus bicolor (Squamata, Gymnophthalmidae)

    PubMed Central

    Hernández-Jaimes, Carlos; Jerez, Adriana; Ramírez-Pinilla, Martha Patricia

    2012-01-01

    The study of cranial design and development in Gymnophthalmidae is important to understand the ontogenetic processes behind the morphological diversity of the group and to examine the possible effects of microhabitat use and other ecological parameters, as well as phylogenetic constraints, on skull anatomy. Complete morphological descriptions of embryonic skull development within Gymnophthalmidae are non-existent. Likewise, very little is known about the complete chondrocranium of the family. Herein, the development of the skull of the semi-fossorial lizard Ptychoglossus bicolor is described along with an examination of the chondrocranium of other gymnophthalmid taxa and the teiid Cnemidophorus lemniscatus. Cranial chondrification begins with early condensations in the ethmoid, orbitotemporal and occipital regions of the chondrocranium as well as the viscerocranium. Ossification of the skull starts with elements of the dermatocranium (pterygoid, prefrontal, maxilla and jugal). The orbitosphenoid is the last chondral bone to appear. At birth, the skull is almost completely ossified and exhibits a large frontoparietal fontanelle. In general terms, the chondrocranium of the gymnophthalmids studied is characteristic of lacertiform terrestrial lizards, in spite of their life habits, and resembles the chondrocranium of C. lemniscatus in many aspects. However, the gymnophthalmids show great variation in the orbitosphenoid and a complex nasal capsule. The latter exhibits greater development of some nasal cartilages, which make it more complex than in C. lemniscatus. These characteristics might be related to microhabitat use and the well-developed olfactory and vomeronasal systems observed within this clade. PMID:22881276

  1. Tertiary climate change and the diversification of the Amazonian gecko genus Gonatodes (Sphaerodactylidae, Squamata).

    PubMed

    Gamble, Tony; Simons, Andrew M; Colli, Guarino R; Vitt, Laurie J

    2008-01-01

    The genus Gonatodes is a monophyletic group of small-bodied, diurnal geckos distributed across northern South America, Central America, and the Caribbean. We used fragments of three nuclear genes (RAG2, ACM4, and c-mos) and one mitochondrial gene (16S) to estimate phylogenetic relationships among Amazonian species of Gonatodes. We used Penalized Likelihood to estimate timing of diversification in the genus. Most cladogenesis occurred in the Oligocene and early Miocene and coincided with a burst of diversification in other South American animal groups including mollusks, birds, and mammals. The Oligocene and early Miocene were periods dominated by dramatic climate change and Andean orogeny and we suggest that these factors drove the burst of cladogenesis in Gonatodes geckos as well as other taxa. A common pattern in Amazonian taxa is a biogeographic split between the eastern and western Amazon basin. We observed two clades with this spatial distribution, although large differences in timing of divergence between the east-west taxon pairs indicate that these divergences were not the result of a common vicariant event.

  2. Omnivory of an Insular Lizard: Sources of Variation in the Diet of Podarcis lilfordi (Squamata, Lacertidae)

    PubMed Central

    Pérez-Cembranos, Ana; León, Alicia; Pérez-Mellado, Valentín

    2016-01-01

    Through 17 years and from a sample of 7,790 faecal pellets and 26,346 prey items, we studied the diet of the Balearic lizard Podarcis lilfordi in Aire Island (Menorca, Balearic Islands, Spain). We analysed the diet in terms of prey frequencies, as well as by their volume and biomass contributions. The diet of the Balearic lizard was extremely variable through the years, months and areas under study. The dominance of small clumped prey, particularly ants, was confirmed. However, the main contribution by volume corresponded to beetles, with a relevant role for Diplopoda and terrestrial Isopoda during some months and at particular areas of the island. Several prey items were probably captured at the base of shrubs, under stones or inside rock crevices. Therefore, our estimations of electivity would only be reliable for epigeal and flying prey. The capacity of the Balearic lizard to include marine subsidies in its diet, such as coastal crustaceans, is noteworthy. Also, its consumption of carrion from carcasses of gulls and rabbits and leftovers from human visitors is remarkable. Juvenile conspecifics can also be a sporadic food resource, especially during the second half of summer, whereas the consumption of vegetal matter is constant for each whole year. The shifts of vegetal exploitation among areas of the island and months take place according to availability of different plant species at each area or during a given period. Thus, lizards are able to conduct a thorough monitoring of plant phenology, exploiting a large variety of plant species. Omnivory does not imply the indiscriminate inclusion of any edible food in its diet. Rather, the inclusion of several food items means the adoption of a wide range of foraging behaviours adapted to the exploitation of each food resource. PMID:26871439

  3. Resurrection of Anolis ustus Cope, 1864 from synonymy with Anolis sericeus Hallowell, 1856 (Squamata, Dactyloidae)

    PubMed Central

    Lara-Tufiño, José Daniel; de Oca, Adrián Nieto-Montes; Ramírez-Bautista, Aurelio; Gray, Levi N.

    2016-01-01

    Abstract In this study, based on a morphological analysis, the resurrection of the name Anolis ustus Cope 1864, is proposed for populations from the Yucatán Peninsula (Campeche, Yucatán, and Quintana Roo, Mexico, and Belize), formerly referred as Anolis sericeus Hallowell, 1856. Anolis ustus differs from Anolis sericeus by its mean snout-vent length and number of gorgetal scales in males, in tibia length and head width in females, and dorsal and ventral scales for both sexes. In addition, Anolis ustus has a small dewlap of similar size between males and females, whereas in Anolis sericeus males have a dewlap much larger than that of the females. These characteristics allow Anolis ustus to be identified within the Anolis sericeus complex. In this study, a description of the characteristics of the hemipenis is also provided, and its importance in the taxonomy of Anolis is discussed. PMID:27829791

  4. A new species of the genus Tropiocolotes Peters, 1880 from western Iran (Squamata: Sauria: Gekkonidae).

    PubMed

    Krause, Valentina; Ahmadzadeh, Faraham; Moazeni, Mostafa; Wagner, Philipp; Wilms, Thomas M

    2013-01-01

    The genus Tropiocolotes comprises small, naked toed, ground dwelling and nocturnal desert geckos, ranging from Morocco and Mauritania in northern Africa to south and central Arabia as well as coastal Iran. Herein, we describe a new species of the genus Tropiocolotes from western Iran based on five specimens from Nayband region. This new taxon is described with a statistical approach based on 34 meristic, metric and qualitative morphological characters of more than 300 individuals of related species.

  5. The presence of Abronia oaxacae (Squamata: Anguidae) in tank bromeliads in temperate forests of Oaxaca, Mexico.

    PubMed

    Cruz-Ruiz, G I; Mondragón, D; Santos-Moreno, A

    2012-05-01

    The presence of lizards in bromeliads has been widely documented. Nevertheless, the possibility of some type of preference or specificity among lizards for particular bromeliad species has not yet been investigated. Therefore, this study aims to document the presence of Abronia oaxacae in six species of tank bromeliads found in pine forests, pine-live oak forests, and live oak groves during both the rainy season and the dry season. Three adult individuals of Abronia oaxacae were collected; one in a Tillandsia violácea (pine-live oak forest), one in a T. calothyrsus (live oak grove), and one in a T. prodigiosa (live oak grove). All three specimens were collected in sampling efforts carried out during the dry season. The results of the present study suggest that A. oaxacae shows no preference for a single, specific bromeliad species, although it does have a certain preference for a few select species. The presence of A. oaxacae in bromeliads during the dry season could be related to the cooler, moister microhabitat that these plants represent.

  6. Examining the utility of categorical models and alleviating artifacts in phylogenetic reconstruction of the Squamata (Reptilia).

    PubMed

    Douglas, D A; Arnason, U

    2009-09-01

    Reconstruction artifacts are a serious hindrance to the elucidation of phylogenetic relationships and a number of methods have been devised to alleviate them. Previous studies have demonstrated a striking disparity in the evolutionary rates of the mitochondrial (mt) genomes of squamate reptiles (lizards, worm lizards and snakes) and the reconstruction artifacts that may arise from this. Here, to examine basal squamate relationships, we have added the mt genome of the blind skink Dibamus novaeguineae to the mitogenomic dataset and applied different models for resolving the squamate tree. Categorical models were found to be less susceptible to artifacts than were the commonly used noncategorical phylogenetic models GTR and mtREV. The application of different treatments to the data showed that the removal of the fastest evolving sites in snakes improved phylogenetic signal in the dataset. Basal divergences remained, nevertheless, poorly resolved. The proportion of both fast-evolving and conserved sites in the squamate mt genomes relative to sites with intermediate rates of evolution suggests rapid early divergences among squamate taxa and at least partly explains the short internal relative to external branches in the squamate tree. Thus, mt and nuclear trees may never reach full agreement because of the short branches characterizing these divergences.

  7. A preliminary phylogeny of the Palearctic naked-toed geckos (Reptilia: Squamata: Gekkonidae) with taxonomic implications.

    PubMed

    Bauer, Aaron M; Masroor, Rafaqat; Titus-McQuillan, James; Heinicke, Matthew P; Daza, Juan D; Jackman, Todd R

    2013-01-08

    Palearctic naked-toed geckos are a group of gekkonid geckos that range from North Africa to northern India and western China, with their greatest diversity in Iran and Pakistan. Relationships among the constituent genera remain incompletely resolved and the monophyly of key genera remains unverified. Further, competing classifications are in current use and many species have been allocated to different genera by different authors. We used both mitochondrial (ND2) and nuclear genes (RAG1, PDC) to explore relationships among representatives of all but one genus in the group (Rhinogecko), including four genera not previously included in phylogenetic analyses (Asiocolotes, Altigekko, Indogekko, and Siwaligekko). Siwaligekko (and presumably other Tibeto-Himalayan species often referred to Cyrtopodion) are more closely related to tropical Asian Cyrtodactylus than to Palearctic naked-toed geckos. Sampled species of Asiocolotes and Altigekko are sister taxa, but both genera are here considered junior subjective synonyms of Altiphylax. Cyrtopodion sensu lato is non-monophyletic; Mediodactylus and Tenuidactylus, which have variably been considered as subgenera or synonyms of Cyrtopodion are both valid genera. Indogekko is embedded within Cyrtopodion and is here treated as a subgenus. Bunopus and Crossobamon are closely related to one-another, and with Agamura are interdigitated among taxa previously assigned to Cyrtopodion. Our data confirm the previous identification of a Saharo-Arabian Stenodactylus/Tropiocolotes/Pseudoceramodactylus clade and verify that Microgecko and Alsophylax are not members of the main clade of Palearctic naked-toed geckos. Osteological differences between Tropiocolotes and Microgecko, formerly treated as congeneric, are discussed and illustrated. The divergence between Cyrtodactylus and the Palearctic naked-toed clade predates the initial collision of the Indian and Eurasian plates, but deeper divergences within both groups are consistent with mountain building in the Himalayas and adjacent ranges as promoting cladogenic events. Miocene divergences within Tenuidactylus are consistent with vicariant speciation caused by uplift events in the Iranian and Transcaspian regions. Taxonomic implications of our phylogenetic results are discussed and a preliminary allocation of all species of padless Palearctic gekkonids to genus is provided.

  8. Diet and conservation implications of an invasive chameleon, Chamaeleo jacksonii (Squamata: Chamaeleonidae) in Hawaii

    USGS Publications Warehouse

    Kraus, Fred; Medeiros, Arthur; Preston, David; Jarnevich, Catherine S.; Rodda, Gordon H.

    2012-01-01

    We summarize information on current distribution of the invasive lizard Chamaeleo jacksonii and predict its potential distribution in the Hawaiian Islands. Potential distribution maps are based on climate models developed from known localities in its native range and its Hawaiian range. We also present results of analysis of stomach contents of a sample of 34 chameleons collected from native, predominantly dryland, forest on Maui. These data are the first summarizing prey range of this non-native species in an invaded native-forest setting. Potential distribution models predict that the species can occur throughout most of Hawaii from sea level to >2,100 m elevation. Important features of this data set are that approximately one-third of the diet of these lizards is native insects, and the lizards are consuming large numbers of arthropods each day. Prey sizes span virtually the entire gamut of native Hawaiian arthropod diversity, thereby placing a large number of native species at risk of predation. Our dietary results contrast with expectations for most iguanian lizards and support suggestions that chameleons comprise a third distinct foraging-mode category among saurians. The combination of expanding distribution, large potential range size, broad diet, high predation rates, and high densities of these chameleons imply that they may well become a serious threat to some of the Hawaiian fauna.

  9. A new species of the genus Calotes Cuvier, 1817 (Squamata: Agamidae) from southern Vietnam.

    PubMed

    Hartmann, Timo; Geissler, Peter; Poyarkov, Nikolay A; Ihlow, Flora; Galoyan, Eduard A; Rödder, Dennis; Böhme, Wolfgang

    2013-01-07

    We describe a new species of the agamid genus Calotes Cuvier, 1817 from southern Vietnam, which is most similar to Calotes mystaceus Duméril & Bibron, 1837, but can be distinguished from the latter and its other congeners by genetic and morphological differences. We discuss the current distribution of the new species and its sister species C. mystaceus in Mainland Southeast Asia.

  10. A new species of Pseudogekko (Squamata: Gekkonidae) from the Romblon Island Group, Central Philippines.

    PubMed

    Siler, Cameron D; Davis, Drew R; Diesmos, Arvin C; Guinto, Faith; Whitsett, Collin; Brown, Rafe M

    2016-07-20

    We describe a new species of lizard in the genus Pseudogekko from Sibuyan and Tablas islands in the Romblon Island Group of the central Philippines. The new species is diagnosed from other Philippine Pseudogekko by body size and shape, color pattern, and multiple differences in scale characteristics. Pseudogekko isapa sp. nov. has been collected only twice from leaves of shrubs in forested habitat on Sibuyan and Tablas islands. The distinctive new species of false gecko is undoubtedly endemic to this single, isolated island group. The fact that populations of such a distinctive new species of Pseudogekko has escaped notice of herpetologists on the reasonably well-studied and largely protected Sibuyan Island further emphasizes the secretive and forest-dependent habits of Philippine false geckos. These characteristics of their behavior and natural history render them difficult to study and challenge biologists' efforts to accurately assess their conservation status.

  11. An ancient lineage of slow worms, genus Anguis (Squamata: Anguidae), survived in the Italian Peninsula.

    PubMed

    Gvoždík, Václav; Benkovský, Norbert; Crottini, Angelica; Bellati, Adriana; Moravec, Jiří; Romano, Antonio; Sacchi, Roberto; Jandzik, David

    2013-12-01

    Four species of legless anguid lizard genus Anguis have been currently recognized: A. fragilis from western and central Europe, A. colchica from eastern Europe and western Asia, A. graeca from southern Balkans, and A. cephallonica from the Peloponnese. Slow worms from the Italian Peninsula have been considered conspecific with A. fragilis, despite the fact that the region served as an important speciation center for European flora and fauna, and included some Pleistocene glacial refugia. We used mitochondrial and nuclear DNA sequences to investigate the systematic and phylogenetic position of the Italian slow-worm populations and morphological analyses to test for phenotypic differentiation from A. fragilis from other parts of Europe. Our phylogenetic analyses revealed that Italian slow worms form a distinct deeply differentiated mtDNA clade, which presumably diverged during or shortly after the basal radiation within the genus Anguis. In addition, the specimens assigned to this clade bear distinct haplotypes in nuclear PRLR gene and show morphological differentiation from A. fragilis. Based on the differentiation in all three independent markers, we propose to assign the Italian clade species level under the name Anguis veronensisPollini, 1818. The newly recognized species is distributed throughout the Italian Peninsula to the Southern Alps and south-eastern France. We hypothesize that the Tertiary Alpine orogeny with subsequent vicariance might have played a role in differentiation of this species. The current genetic variability was later presumably shaped in multiple glacial refugia within the Italian Peninsula, with the first splitting event separating populations from the region of the Dolomite Mountains.

  12. Molecular cytogenetic map of the central bearded dragon, Pogona vitticeps (Squamata: Agamidae).

    PubMed

    Young, M J; O'Meally, D; Sarre, S D; Georges, A; Ezaz, T

    2013-07-01

    Reptiles, as the sister group to birds and mammals, are particularly valuable for comparative genomic studies among amniotes. The Australian central bearded dragon (Pogona vitticeps) is being developed as a reptilian model for such comparisons, with whole-genome sequencing near completion. The karyotype consists of 6 pairs of macrochromosomes and 10 pairs microchromosomes (2n = 32), including a female heterogametic ZW sex microchromosome pair. Here, we present a molecular cytogenetic map for P. vitticeps comprising 87 anchor bacterial artificial chromosome clones that together span each macro- and microchromosome. It is the first comprehensive cytogenetic map for any non-avian reptile. We identified an active nucleolus organizer region (NOR) on the sub-telomeric region of 2q by mapping 18S rDNA and Ag-NOR staining. We identified interstitial telomeric sequences in two microchromosome pairs and the W chromosome, indicating that microchromosome fusion has been a mechanism of karyotypic evolution in Australian agamids within the last 21 to 19 million years. Orthology searches against the chicken genome revealed an intrachromosomal rearrangement of P. vitticeps 1q, identified regions orthologous to chicken Z on P. vitticeps 2q, snake Z on P. vitticeps 6q and the autosomal microchromosome pair in P. vitticeps orthologous to turtle Pelodiscus sinensis ZW and lizard Anolis carolinensis XY. This cytogenetic map will be a valuable reference tool for future gene mapping studies and will provide the framework for the work currently underway to physically anchor genome sequences to chromosomes for this model Australian squamate.

  13. Sex Chromosomes and Karyotype of the (Nearly) Mythical Creature, the Gila Monster, Heloderma suspectum (Squamata: Helodermatidae)

    PubMed Central

    Pokorná, Martina Johnson; Rovatsos, Michail; Kratochvíl, Lukáš

    2014-01-01

    A wide variety of sex determination systems exist among squamate reptiles. They can therefore serve as an important model for studies of evolutionary transitions among particular sex determination systems. However, we still have only a limited knowledge of sex determination in certain important lineages of squamates. In this respect, one of the most understudied groups is the family Helodermatidae (Anguimorpha) encompassing the only two venomous species of lizards which are potentially lethal to human beings. We uncovered homomorphic ZZ/ZW sex chromosomes in the Gila monster (Heloderma suspectum) with a highly heterochromatic W chromosome. The sex chromosomes are morphologically similar to the ZZ/ZW sex chromosomes of monitor lizards (Varanidae). If the sex chromosomes of helodermatids and varanids are homologous, female heterogamety may be ancestral for the whole Anguimorpha group. Moreover, we found that the karyotype of the Gila monster consists of 2n = 36 chromosomes (14 larger metacentric chromosomes and 22 acrocentric microchromosomes). 2n = 36 is the widely distributed chromosomal number among squamates. In his pioneering works representing the only previous cytogenetic examination of the family Helodermatidae, Matthey reported the karyotype as 2n = 38 and suggested a different chromosomal morphology for this species. We believe that this was probably erroneously. We also discovered a strong accumulation of telomeric sequences on several pairs of microchromosomes in the Gila monster, which is a trait documented relatively rarely in vertebrates. These new data fill an important gap in our understanding of the sex determination and karyotype evolution of squamates. PMID:25119263

  14. Species delimitation using Bayes factors: simulations and application to the Sceloporus scalaris species group (Squamata: Phrynosomatidae).

    PubMed

    Grummer, Jared A; Bryson, Robert W; Reeder, Tod W

    2014-03-01

    Current molecular methods of species delimitation are limited by the types of species delimitation models and scenarios that can be tested. Bayes factors allow for more flexibility in testing non-nested species delimitation models and hypotheses of individual assignment to alternative lineages. Here, we examined the efficacy of Bayes factors in delimiting species through simulations and empirical data from the Sceloporus scalaris species group. Marginal-likelihood scores of competing species delimitation models, from which Bayes factor values were compared, were estimated with four different methods: harmonic mean estimation (HME), smoothed harmonic mean estimation (sHME), path-sampling/thermodynamic integration (PS), and stepping-stone (SS) analysis. We also performed model selection using a posterior simulation-based analog of the Akaike information criterion through Markov chain Monte Carlo analysis (AICM). Bayes factor species delimitation results from the empirical data were then compared with results from the reversible-jump MCMC (rjMCMC) coalescent-based species delimitation method Bayesian Phylogenetics and Phylogeography (BP&P). Simulation results show that HME and sHME perform poorly compared with PS and SS marginal-likelihood estimators when identifying the true species delimitation model. Furthermore, Bayes factor delimitation (BFD) of species showed improved performance when species limits are tested by reassigning individuals between species, as opposed to either lumping or splitting lineages. In the empirical data, BFD through PS and SS analyses, as well as the rjMCMC method, each provide support for the recognition of all scalaris group taxa as independent evolutionary lineages. Bayes factor species delimitation and BP&P also support the recognition of three previously undescribed lineages. In both simulated and empirical data sets, harmonic and smoothed harmonic mean marginal-likelihood estimators provided much higher marginal-likelihood estimates than PS and SS estimators. The AICM displayed poor repeatability in both simulated and empirical data sets, and produced inconsistent model rankings across replicate runs with the empirical data. Our results suggest that species delimitation through the use of Bayes factors with marginal-likelihood estimates via PS or SS analyses provide a useful and complementary alternative to existing species delimitation methods.

  15. Molecular systematics and undescribed diversity of Madagascan scolecophidian snakes (Squamata: Serpentes).

    PubMed

    Nagy, Zoltán T; Marion, Angela B; Glaw, Frank; Miralles, Aurélien; Nopper, Joachim; Vences, Miguel; Hedges, S Blair

    2015-11-10

    We provide an updated molecular phylogenetic analysis of global diversity of typhlopid and xenotyphlopid blindsnakes, adding a set of Madagascan samples and sequences of an additional mitochondrial gene to an existing supermatrix of nuclear and mitochondrial gene segments. Our data suggest monophyly of Madagascan typhlopids, exclusive of introduced Indotyphlops braminus. The Madagascar-endemic typhlopid clade includes two species previously assigned to the genus Lemuriatyphlops (in the subfamily Asiatyphlopinae), which were not each others closest relatives. This contradicts a previous study that described Lemuriatyphlops based on a sequence of the cytochrome oxidase subunit 1 gene from a single species and found this species not forming a clade with the other Malagasy species included. Based on our novel phylogenetic assessment we include all species in this endemic typhlopid clade in the genus Madatyphlops and in the subfamily Madatyphlopinae and consider Lemuriatyphlops as junior synonym. Within Madatyphlops, we identify several candidate species. For some of these (those in the M. arenarius complex), our preliminary data suggest sympatric occurrence and morphological differentiation, thus the existence of undescribed species. We also comment on the genus-level classification of several non-Madagascan typhlopids. We suggest that African species included in Madatyphlops (Afrotyphlops calabresii, A. cuneirostris, A. platyrhynchus, and Rhinotyphlops leucocephalus) should not be included in this genus. We furthermore argue that recent claims of Sundatyphlops, Antillotyphlops, and Cubatyphlops being "undiagnosable" or "not monophyletic" were based on errors in tree reconstruction and failure to notice diagnostic characters, and thus regard these three genera as valid.

  16. Histological and morphological observations on tongue of Scincella tsinlingensis (Reptilia, Squamata, Scincidae).

    PubMed

    Yang, Chun; Wang, Limin

    2016-01-01

    The histology and morphology characteristics of the tongue in Scincella tsinlingensis were studied by light and electronic microscopy. Under light microscopy, the tongue consists of tip, lingual body and radix in sequence. Numerous lingual papillae widely distribute on the surface of the dorsal and ventral flanks in the tongue, in addition to some regions of the tip. The papillae's surface is covered with the epithelial layer. The lamina propria and dense connective tissue are distinct existing under the epithelial layer. There are many lingual glands spread over the lamina propria. Tongue muscle is developed and composed of distinct intrinsic muscle, hyoglossus and genioglossus. By scanning electron microscopy, at higher magnification, the epithelial cells of the dorsal surface in the divaricate tongue tips show numerous microvilli, micro-ridges and micro-pores. The surface of dorsal side of the papillae in lingual body is covered with abundant of micro-ridges and taste bud lacuna. On the surface of the papillae in radix, micro-facets and micro-ridges are compactly distributed, as well as scattered mucilage-pores. The lingual epithelium is divided into four layers observed by the transmission electron microscope. Cells of basal layer are irregularly elliptical in shape, with sparse organelles in the cytoplasm. The deep intermediate layer is not always distinct. Small numbers of organelles are scattered into the cytoplasm. The cells of the superficial intermediate layer gradually flatten, as do their nuclei. The cytoplasm contains many keratohyalin granules. Cell membranes are formed processes around cells and joined by abundant desmosomes to the cell membranes of adjacent cells. The cells located on the extreme free-surface side of the keratinized layer have fallen off. The basal lamina is intercalated between the basal layer and the lamina propria. The lamina propria of lingual body contains lingual gland. A large part of the cytoplasm is occupied by mucus granules which located in the distal part of the cell. The connective tissue contains myelinated nerve fibers, vessel and muscle cells.

  17. A new species of gecko (Squamata: Diplodactylidae: Strophurus) from north Queensland, Australia.

    PubMed

    Vanderduys, Eric

    2016-06-01

    A new species of diplodactylid gecko in the genus Strophurus Fitzinger, from north Queensland, Australia, is described herein as Strophurus congoo sp. nov. It is a small, pale grey to tan, unpatterned or faintly striped gecko, resembling the phasmid geckos in appearance, habitat and behaviour. However, within Strophurus it is not closely related to the phasmid geckos. It is distinguished from all other Strophurus by a combination of even scalation, dull colouration, small size and short tail length. It is only known to occur in a restricted area of the northern Great Dividing Range, within the Einasleigh Uplands bioregion, in a relatively infertile area of rolling, largely granitic hills, and is only known from spinifex (Triodia) hummock grasslands in open woodland.

  18. A new Bent-toed Gecko (Squamata: Gekkonidae: Cyrtodactylus) from Phetchaburi Province, Thailand.

    PubMed

    Pauwels, Olivier S G; Sumontha, Montri; Bauer, Aaron M

    2016-03-09

    A new Bent-toed Gecko, Cyrtodactylus phetchaburiensis sp. nov. is described from the Tha Yang District of Phetchaburi Province, western Thailand. It is a medium-sized Cyrtodactylus (SVL to at least 63.2 mm), with small, mostly keeled tubercles in 20 regular longitudinal rows on dorsum; 33 scales across mid-venter between lowest rows of flank tubercles; enlarged row of femoral scales present; five precloacal pores in male, femoral pores and precloacal groove absent; 5-6 broad basal lamellae and 11 narrow distal lamellae beneath digit IV of pes; and a single median row of transversely enlarged subcaudal scales present. It has a dorsal colour pattern of large, dark, diffusely-edged markings on a fawn background and a pair of dark scapular patches. The species is a member of the Central Indochinese (Thai-Myanmar) clade of Cyrtodactylus and is most closely related to C. oldhami (Theobald), from which it differs in colour pattern.

  19. A new species of dwarf gecko in the genus Lygodactylus (squamata: Gekkonidae) from central Kenya.

    PubMed

    Malonza, Patrick K; Granthon, Carolina; Williams, Dean A

    2016-01-08

    A new species of Lygodactylus gecko (L. wojnowskii sp. nov.) is described from the vicinity of Chogoria Town on the eastern lower slopes of Mt. Kenya in central Kenya. A phylogeny based on mitochondrial and nuclear DNA shows that the proposed new taxon is distinct within the Lygodactylus picturatus group and is the sister lineage to L. mombasicus and L. kimhowelli. It is morphologically very similar to both L. mombasicus and L. keniensis but its dorsal coloration and pattern is different. Its dorsum is grey with dark stripes while its head has black and white stripes that form a Y-shaped mark. While the male throat pattern is similar to that of L. mombasicus, that of the female is like that of females and some males of Lygodactylus keniensis. Lygodactylus wojnowskii sp. nov. has a higher number of post-postmental scales (6) than do its close relatives (5). The new species is distributed on the lower slopes of mid-altitude areas on eastern Mt. Kenya, but it may occur in other areas at similar elevations in central Kenya. It is associated with short, scattered trees within agricultural areas. It has not yet been recorded within the protected Chogoria forest block of Mt. Kenya forest. It is likely present in Mwea National Reserve as it occurs in nearby areas.

  20. A new Bent-toed gecko (Squamata: Gekkonidae) from the Mekongga Mountains, South East Sulawesi, Indonesia.

    PubMed

    Riyanto, Awal; Kurniati, Hellen; Engilis, Andrew

    2016-05-05

    We describe Cyrtodactylus hitchi sp. nov., a new species of Bent-toed Gecko from montane forests in the Mekongga Mountains, South East Sulawesi, Indonesia. Although we cannot speculate about relationships, morphologically it shares several traits with C. batik, a large species known only from Mount Tompotika near the tip of Sulawesi's Eastern Peninsula. The following unique combination of characters distinguishes it from all other congeners: absence of precloacal groove, absence of precloacal and femoral pores, absence of enlarged femoral scales, no abrupt contact between large and small postfemoral scales, 18-20 lamellae under the fourth toes, and transversely enlarged, median subcaudal scales arranged in a single row.

  1. Low rate of interchromosomal rearrangements during old radiation of gekkotan lizards (Squamata: Gekkota).

    PubMed

    Johnson Pokorná, Martina; Trifonov, Vladimir A; Rens, Willem; Ferguson-Smith, Malcolm A; Kratochvíl, Lukáš

    2015-06-01

    Gekkotan lizards are a highly specious (∼1600 described species) clade of squamate lizards with nearly cosmopolitan distribution in warmer areas. The clade is primarily nocturnal and forms an ecologically dominant part of the world nocturnal herpetofauna. However, molecular cytogenetic methods to study the evolution of karyotypes have not been widely applied in geckos. Our aim here was to uncover the extent of chromosomal rearrangements across the whole group Gekkota and to search for putative synapomorphies supporting the newly proposed phylogenetic relationships within this clade. We applied cross-species chromosome painting with the recently derived whole-chromosomal probes from the gekkonid species Gekko japonicus to members of the major gekkotan lineages. We included members of the families Diplodactylidae, Carphodactylidae, Pygopodidae, Eublepharidae, Phyllodactylidae and Gekkonidae. Our study demonstrates relatively high chromosome conservatism across the ancient group of gekkotan lizards. We documented that many changes in chromosomal shape across geckos can be attributed to intrachromosomal rearrangements. The documented rearrangements are not totally in agreement with the recently newly erected family Phyllodactylidae. The results also pointed to homoplasy, particularly in the reuse of chromosome breakpoints, in the evolution of gecko karyotypes.

  2. Unique features of myogenesis in Egyptian cobra (Naja haje) (Squamata: Serpentes: Elapidae).

    PubMed

    Khannoon, Eraqi R; Rupik, Weronika; Lewandowski, Damian; Dubińska-Magiera, Magda; Swadźba, Elwira; Daczewska, Małgorzata

    2016-03-01

    During early stages of myotomal myogenesis, the myotome of Egyptian cobra (Naja haje) is composed of homogenous populations of mononucleated primary myotubes. At later developmental phase, primary myotubes are accompanied by closely adhering mononucleated cells. Based on localization and morphology, we assume that mononucleated cells share features with satellite cells involved in muscle growth. An indirect morphological evidence of the fusion of mononucleated cells with myotubes is the presence of numerous vesicles in the subsarcolemmal region of myotubes adjacent to mononucleated cell. As differentiation proceeded, secondary muscle fibres appeared with considerably smaller diameter as compared to primary muscle fibre. Studies on N. haje myotomal myogenesis revealed some unique features of muscle differentiation. TEM analysis showed in the N. haje myotomes two classes of muscle fibres. The first class was characterized by typical for fast muscle fibres regular distribution of myofibrils which fill the whole volume of muscle fibre sarcoplasm. White muscle fibres in studied species were a prominent group of muscles in the myotome. The second class showed tightly paced myofibrils surrounding the centrally located nucleus accompanied by numerous vesicles of different diameter. The sarcoplasm of these cells was characterized by numerous lipid droplets. Based on morphological features, we believe that muscle capable of lipid storage belong to slow muscle fibres and the presence of lipid droplets in the sarcoplasm of these muscles during myogenesis might be a crucial adaptive mechanisms for subsequent hibernation in adults. This phenomenon was, for the first time, described in studies on N. haje myogenesis.

  3. Catalogue of distribution of lizards (Reptilia: Squamata) from the Brazilian Amazonia. II. Gekkonidae, Phyllodactylidae, Sphaerodactylidae.

    PubMed

    Ribeiro-Júnior, Marco A

    2015-07-02

    I present distribution data of all geckos (Gekkonidae, Phyllodactylidae and Sphaerodactylidae) known from the Brazilian Amazonia, totaling 19 species, belonging to nine genera. This represents six more taxa than previously reported for these families. Data were based on the direct examination of 23,094 specimens deposited in three North American and eight Brazilian museums. Most species (68.4%) are endemic to the Amazonia; non-endemic species are mainly associated with open dry (semideciduous) forest or open vegetation (savanna) enclaves in Amazonia. As a whole, three taxa are widespread in Amazonia, two are restricted to eastern Amazonia, two to western Amazonia, three to northern Amazonia (either widespread or restriced to parts of the Guiana region), one to southern Amazonia, one to southwestern Amazonia, and three to the southern peripheral portion of Amazonia. Additionally, four species have unique distributions and four species have a distribution that is congruent with one of the areas of endemism recognized for other organisms (birds and primates), of which two occur in the area of endemism of Guiana, one in Inambari, and one in Tapajós.

  4. Catalogue of distribution of lizards (Reptilia: Squamata) from the Brazilian Amazonia. III. Anguidae, Scincidae, Teiidae.

    PubMed

    Ribeiro-Júnior, Marco A; Amaral, Silvana

    2016-12-09

    We present distribution data of all Anguidae, Scincidae, and Teiidae lizards known from the Brazilian Amazonia, totaling 29 species-level taxa, belonging to 14 genera. This represents 11 more species-level taxa than previously reported for these families in this area. Data were based on literature and 46,806 specimens deposited in three North American and eight Brazilian museums, including the main collections harboring Amazonian material. Most species (~55%) are endemic to Amazonia. Except for Ameiva ameiva, that is present in several environments and domains, non-endemic species are either associated with open dry (semideciduous) forest or open vegetation (savanna) enclaves in Amazonia, occupying similar environments outside Amazonia, gallery forests within the Cerrado, or present disjunct populations in the Atlantic Forest. As a whole, six taxa are widespread in Amazonia, four are restricted to eastern Amazonia, four to western Amazonia, three to southwestern Amazonia, one to northern Amazonia, and seven to the southern peripheral portion of Amazonia. Besides, two species present apparently more restricted, unique distributions. Only three species have a distribution that is congruent with one of the areas of endemism (AE) recognized for other organisms (birds and primates), of which two occur in AE Guiana and one in AE Inambari.

  5. The phylogenetic relationships of Pachyrhachis problematicus, and the evolution of limblessness in snakes (Lepidosauria, Squamata)

    NASA Astrophysics Data System (ADS)

    Zaher, Hussam; Rieppel, Olivier

    1999-12-01

    We have revisited the type material of Pachyrhachis problematicus, a fossil snake from the Cenomanian (Cretaceous) of the Middle East, and found a number of characters in need of revision with respect to its recent re-description. A new interpretation is given for several cranial characters. There is no identifiable regionalization of the presacral-vertebral column beyond that found in booid snakes. The identification of a free sacral rib in Pachyrhachis is more parsimoniously interpreted as the first lymphapophysis. It is questionable that the pelvic rudiment would have been suspended from the axial skeleton. We have also extensively reviewed the evidence that is believed to link Pachyrhachis, and with it all other snakes, to a mosasauroid ancestor. We were not able to corroborate this hypothesis, which involves characters related to the dentition, braincase morphology, and the intramandibular joint. Instead, re-analysis of the phylogenetic relationships of Pachyrhachis corroborates the hypothesis that it represents the sister-group of macrostomatan snakes, i.e., advanced snakes. Given that Pachyrhachis is nested within the hierarchy of snakes, it is entirely possible that this snake re-developed almost complete hind limbs. A less parsimonious hypothesis would be to consider the hind limbs to have been lost independently in the major basal clades of extant snakes (Scolecophidia, Anilioidea, and Macrostomata). The latter hypothesis is considered a serious possibility given the recently described findings on the mechanisms of limb development in Python, which could account for the highly variable pattern of hindlimb reduction found among basal snakes.

  6. The peak of thermoregulation effectiveness: Thermal biology of the Pyrenean rock lizard, Iberolacerta bonnali (Squamata, Lacertidae).

    PubMed

    Ortega, Zaida; Mencía, Abraham; Pérez-Mellado, Valentín

    2016-02-01

    We studied, at 2200m altitude, the thermal biology of the Pyrenean rock lizard, Iberolacerta bonnali, in the glacial cirque of Cotatuero (National Park of Ordesa, Huesca, Spain). The preferred thermal range (PTR) of I. bonnali indicates that it is a cold-adapted ectotherm with a narrow PTR (29.20-32.77°C). However, its PTR (3.57°C) is twice as wide as other Iberolacerta lizards, which may be explained by its broader historical distribution. The studied area is formed by a mosaic of microhabitats which offer different operative temperatures, so that lizards have, throughout their entire daily period of activity, the opportunity to choose the most thermally suitable substrates. I. bonnali achieves an effectiveness of thermoregulation of 0.95, which makes it the highest value found to date among the Lacertidae, and one of the highest among lizards. Their relatively wide distribution, their wider PTR, and their excellent ability of thermoregulation, would make I. bonnali lizards less vulnerable to climate change than other species of Iberolacerta. Thanks to its difficult access, the studied area is not visited by a large number of tourists, as are other areas of the National Park. Thus, it is a key area for the conservation of the Pyrenean rock lizard. By shuttling between suitable microhabitats, lizards achieve suitable body temperatures during all day. However, such thermally suitable microhabitats should vary in other traits than thermal quality, such as prey availability or predation risk. Hence, it seems that these not-thermal traits are not constraining habitat selection and thermoregulation in this population. Therefore, future research in this population may study the causes that would lead lizards to prioritize thermoregulation to such extent in this population.

  7. A new species of Bachia (Squamata: Gymnophthalmidae) with pleisomorphic limb morphology

    USGS Publications Warehouse

    Kizirian, D.A.; McDiarmid, R.W.

    1998-01-01

    We describe a new species of Bachia from the upper Rio Negro drainage of southeastern Colombia and southern Venezuela. The new taxon is diagnosed by a complement of phalanges that is unique among gymnophthalmid lizards and intermediate relative to other Bachia and closely related genera. Variation in limb osteology among the species of Bachia and close relatives is reported. We discuss the distribution of B. panoplia and the taxonomic status of B. flavescens.

  8. Omnivory of an Insular Lizard: Sources of Variation in the Diet of Podarcis lilfordi (Squamata, Lacertidae).

    PubMed

    Pérez-Cembranos, Ana; León, Alicia; Pérez-Mellado, Valentín

    2016-01-01

    Through 17 years and from a sample of 7,790 faecal pellets and 26,346 prey items, we studied the diet of the Balearic lizard Podarcis lilfordi in Aire Island (Menorca, Balearic Islands, Spain). We analysed the diet in terms of prey frequencies, as well as by their volume and biomass contributions. The diet of the Balearic lizard was extremely variable through the years, months and areas under study. The dominance of small clumped prey, particularly ants, was confirmed. However, the main contribution by volume corresponded to beetles, with a relevant role for Diplopoda and terrestrial Isopoda during some months and at particular areas of the island. Several prey items were probably captured at the base of shrubs, under stones or inside rock crevices. Therefore, our estimations of electivity would only be reliable for epigeal and flying prey. The capacity of the Balearic lizard to include marine subsidies in its diet, such as coastal crustaceans, is noteworthy. Also, its consumption of carrion from carcasses of gulls and rabbits and leftovers from human visitors is remarkable. Juvenile conspecifics can also be a sporadic food resource, especially during the second half of summer, whereas the consumption of vegetal matter is constant for each whole year. The shifts of vegetal exploitation among areas of the island and months take place according to availability of different plant species at each area or during a given period. Thus, lizards are able to conduct a thorough monitoring of plant phenology, exploiting a large variety of plant species. Omnivory does not imply the indiscriminate inclusion of any edible food in its diet. Rather, the inclusion of several food items means the adoption of a wide range of foraging behaviours adapted to the exploitation of each food resource.

  9. Muscle fiber-type variation in lizards (Squamata) and phylogenetic reconstruction of hypothesized ancestral states.

    PubMed

    Bonine, Kevin E; Gleeson, Todd T; Garland, Theodore

    2005-12-01

    Previously, we found that phrynosomatid lizards, a diverse group common in the southwestern USA, vary markedly in fiber-type composition of the iliofibularis (a hindlimb muscle important in locomotion). Phrynosomatidae comprises three subclades: the closely related sand and horned lizards, and their relatives the Sceloporus group. The variation in muscle fiber-type composition for 11 phrynosomatid species is attributable mainly to differences between the sand- and horned-lizard subclades. Here, we expand the phrynosomatid database with three additional species and compare these results with data collected for 10 outgroup (distantly related) species. Our goal was to determine if the patterns found in Phrynosomatidae hold across a broader phylogenetic range of the extant lizards and to elucidate the evolution of muscle fiber-type composition and related traits. To allow for meaningful comparisons, data were collected from species that are primarily terrestrial and relatively small in size (3.5-65 g body mass). Results indicate that the fiber-type variation observed within the Phrynosomatidae almost spans the range of variation observed in our sample of 24 species from eight families. However, one species of Acanthodactylus (Lacertidae) had a consistent region of large tonic fibers (that did not stain darkly for either succinic dehydrogenase or myosin ATPase activity), a fiber-type only occasionally seen in the other 23 species examined. Many species have a large proportion of either fast-twitch glycolytic (FG; e.g. sand lizards and Aspidoscelis) or fast-twitch oxidative-glycolytic (FOG) fibers (e.g. horned lizards), with the slow-oxidative proportion occupying only 1-17% of the iliofibularis. Importantly, the negative relationship between FG and FOG composition observed in Phrynosomatidae appears to be a characteristic of lizards in general, and could lead to functional trade-offs in aspects of locomotor performance, as has previously been reported for Lacertidae. Reconstruction of ancestral trait values by use of phylogenetically based statistical methods indicates especially large changes in fiber-type composition during the evolution of horned lizards.

  10. Comparative analysis of fiber-type composition in the iliofibularis muscle of phrynosomatid lizards (Squamata).

    PubMed

    Bonine, K E; Gleeson, T T; Garland, T

    2001-12-01

    The lizard family Phrynosomatidae comprises three subclades: the closely related sand and horned lizards, and their relatives the Sceloporus group. This family exhibits great variation in ecology, behavior, and general body plan. Previous studies also show that this family exhibits great diversity in locomotor performance abilities; as measured on a high-speed treadmill, sand lizards are exceptionally fast sprinters, members of the Sceloporus group are intermediate, and horned lizards are slowest. These differences are paralleled by differences in relative hindlimb span. To determine if muscle fiber-type composition also varies among the three subclades, we examined the iliofibularis (IF), a hindlimb muscle used in lizard locomotion, in 11 species of phrynosomatid lizards. Using histochemical assays for myosin ATPase, an indicator of fast-twitch capacity, and succinic dehydrogenase, denoting oxidative capacity, we classified fiber types into three categories based on existing nomenclature: fast-twitch glycolytic (FG), fast-twitch oxidative-glycolytic (FOG), and slow-twitch oxidative (SO). Sand lizards have a high proportion of FG fibers (64-70%) and a low proportion of FOG fibers (25-33%), horned lizards are the converse (FG fibers 25-31%, FOG fibers 56-66%), and members of the Sceloporus group are intermediate for both FG (41-48%) and FOG (42-45%) content. Hence, across all 11 species %FOG and %FG are strongly negatively correlated. Analysis with phylogenetically independent contrasts indicate that this negative relationship is entirely attributable to the divergence between sand and horned lizards. The %SO also varies among the three subclades. Results from conventional nested ANCOVA (with log body mass as a covariate) indicate that the log mean cross-sectional area of individual muscle fibers differs among species and is positively correlated with body mass across species, but does not differ significantly among subclades. The log cross-sectional area of the IF varies among species, but does not vary among subclades. Conversely, the total thigh muscle cross-sectional area does not vary among species, but does vary among subclades; horned lizards have slimmer thighs. Muscle fiber-type composition appears to form part of a coadapted suite of traits, along with relative limb and muscle sizes, that affect the locomotor abilities of phrynosomatid lizards.

  11. Basic ecology of the Oaxacan Spiny-tailed Iguana Ctenosaura oaxacana (Squamata: Iguanidae), in Oaxaca, Mexico.

    PubMed

    Rioja, Tamara; Carrillo-Reyes, Arturo; Espinoza-Medinilla, Eduardo; López-Mendoza, Sergio

    2012-12-01

    The Oaxacan Spiny-tailed Iguana Ctenosaura oaxacana is a restricted species to the Isthmus of Tehuantepec in Southern Oaxaca, Mexico. This reptile is one of the less known iguanid species. We census-tracked a population in the South ofNiltepec, Oaxaca, Mexico from May 2010 to April 2011. Throughout one year, a total of 10 line transects were situated and recorded in the study area to determine relative abundance and density, and habitat type use (dry forest, Nanchal, grassland, riparian vegetation, and mangrove) by the species. This study reports a new C. oaxacana population on the Southeastern limit of species range. Although this species has a very restricted distribution and is in danger of extinction, C. oaxacana has a high population density when compared to other Ctenosaura species. A total of 108 individuals were recorded throughout the study. Dry forest (33.75ind/ha) and Nanchal (18.75ind/ha) were the habitats with higher densities. Comparisons between habitat types showed no significant differences between dry forest and Nanchal (W=15, p=0.0808). Results between seasons were similar. The Oaxacan Spiny tailed Iguana preferred first the dry forest, and then Nanchal, while avoided grassland, riparian vegetation, and mangroves. There was no difference in habitat use between males and females. Mean perch heights were 1.23 +/- 0.32 (n=30) in Nanchal, 2.11 +/- 0.30 (n=9) in grassland, 1.90 +/- 0.56 (n=54) in dry forest, 1.91 +/- 0.28 (n=9) in mangrove and 2.30 +/- 0.37 (n=6) in riparian vegetation. Species observed as refuge and perch were B. crassifolia (Nanchal); C. alata (grassland); Tabebuia sp., Genipa americana, G. sepium, Acacia sp., Ficus sp. and Haematoxylon sp. (dry forest); G. sepium, Acacia sp. and Guazuma ulmifolia (riparian vegetation); and C. erecta (mangrove). Live trees hollows and branches were used by species. Main threats to the species are excessive hunting and habitat loss. Furthermore, grassland fires are still common in the study area during the dry season, which can result in habitat loss and territorial displacement of individuals.

  12. Species-specific evolution of class I MHC genes in iguanas (order: Squamata; subfamily: Iguaninae).

    PubMed

    Glaberman, Scott; Caccone, Adalgisa

    2008-07-01

    Over the last few decades, the major histocompatibility complex (MHC) has emerged as a model for understanding the influence of natural selection on genetic diversity in populations as well as for investigating the genetic basis of host resistance to pathogens. However, many vertebrate taxa remain underrepresented in the field of MHC research, preventing its application to studies of disease, evolution, and conservation genetics in these groups. This is particularly true for squamates, which are by far the most diversified order of non-avian reptiles but have not been the subject of any recent MHC studies. In this paper, we present MHC class I complementary DNA data from three squamate species in the subfamily Iguaninae (iguanas): the Galápagos marine iguana (Amblyrhynchus cristatus), the Galápagos land iguana (Conolophus subcristatus), and the green iguana (Iguana iguana). All sequences obtained are related to the few published class I genes from other squamates. There is evidence for multiple loci in each species, and the conserved alpha-3 domain appears to be evolving in a species-specific manner. Conversely, there is some indication of shared polymorphism between species in the peptide-binding alpha-1 and alpha-2 domains, suggesting that these two regions have different phylogenetic histories. The great similarity between alpha-3 sequences in marine iguanas in particular suggests that concerted evolution is acting to homogenize class I loci within species. However, while less likely, the data are also compatible with a birth and death model of evolution.

  13. Nitrogen excretion during embryonic development of the green iguana, Iguana iguana (Reptilia; Squamata).

    PubMed

    Sartori, M R; Taylor, E W; Abe, A S

    2012-10-01

    Development within the cleidoic egg of birds and reptiles presents the embryo with the problem of accumulation of wastes from nitrogen metabolism. Ammonia derived from protein catabolism is converted into the less toxic product urea or relatively insoluble uric acid. The pattern of nitrogen excretion of the green iguana, Iguana iguana, was determined during embryonic development using samples from allantoic fluid and from the whole homogenized egg, and in hatchlings and adults using samples of blood plasma. Urea was the major excretory product over the course of embryonic development. It was found in higher concentrations in the allantoic sac, suggesting that there is a mechanism present on the allantoic membrane enabling the concentration of urea. The newly hatched iguana still produced urea while adults produced uric acid. The time course of this shift in the type of nitrogen waste was not determined but the change is likely to be related to the water relations associated with the terrestrial habit of the adult. The green iguana produces parchment-shelled eggs that double in mass during incubation due to water absorption; the eggs also accumulate 0.02 mM of urea, representing 82% of the total measured nitrogenous residues that accumulate inside the allantois. The increase in egg mass and urea concentration became significant after 55 days of incubation then were unchanged until hatching.

  14. Systematic revision of the Malagasy chameleons Calumma boettgeri and C. linotum (Squamata: Chamaeleonidae).

    PubMed

    Prötzel, David; Ruthensteiner, Bernhard; Scherz, Mark D; Glaw, Frank

    2015-11-25

    We revise the taxonomic status of two species of Madagascan chameleons in light of a recent molecular phylogenetic study on the Calumma nasutum group. The investigation of morphological and osteological characters led to a clear delineation between two species within the C. boettgeri complex, C. boettgeri and C. linotum. Calumma linotum has been considered either a synonym of C. boettgeri or a dubious, poorly defined taxon. So far it has only been known from the male holotype with the imprecise locality 'Madagascar'. Based on pholidosis, morphological measurements and characters of the skull that were analyzed using micro-X-ray computed tomography (micro-CT) scans, we ascribe the population of chameleons from Montagne d'Ambre, formerly assigned to C. boettgeri, to C. linotum. Calumma linotum differs from C. boettgeri in the larger size of tubercle scales on the extremities and rostral appendage, the larger diameter of the extremities relative to the body size, the presence of a parietal crest as well as the form of the nasal bones and the anterior tip of the frontal. The life colouration of the males is also characteristic, with a blue rostral appendage and greenish turquoise extremities. The body and rostral appendage of C. boettgeri in contrast are inconspicuously yellowish brown coloured. All confirmed distribution records of C. boettgeri are confined to the biogeographic Sambirano region whereas C. linotum is only known from Montagne d'Ambre and a locality at the base of the Tsaratanana massif. Additional literature records of C. boettgeri and C. linotum from northeastern Madagascar are in need of confirmation. We also confirm the synonymy of Chamaeleo macrorhinus (described from a female holotype with an unknown locality) with Calumma boettgeri. The use of micro-CT exposed further characteristics for species delimitation in an integrative taxonomic approach. In addition to the skull, we also micro-CT scanned the hemipenes of C. boettgeri and C. linotum, using an iodine-based tissue stain, and provide 3D PDF models of these organs. This method enables detailed illustration and the detection of variation in particular characters, and might be an important tool in further taxonomic studies on the C. nasutum group and other squamate reptiles.

  15. Habitat use in eight populations of Sceloporus grammicus (Squamata: Phrynosomatidae) from the Mexican Plateau.

    PubMed

    Leyte-Manrique, A; Hernández-Salinas, U; Ramírez-Bautista, A; Mata-Silva, V; Marshall, J C

    2016-10-13

    Studies on habitat use have often helped explain observed variation in morphology, behavior, and reproductive characteristics among populations within a single species. Here we analyze morphological and ecological characteristics of individuals from the Sceloporus grammicus species complex from seven different localities (El Cerezo: CER, Pachuca: PAC, Huichapan: HUI, Emiliano Zapata: EZA, San Miguel Regla: SMR, La Mojonera: LMJ, and La Manzana: LMZ) in the state of Hidalgo, and one locality (Cahuacán) in the State of México. A canonical correspondence analysis (CCA) showed that females from PAC, EZA, LMZ, HUI, SMR, and CAH populations use similar microhabitats characterized mostly by bare soil; while females from LMJ and CER use microhabitats characterized primarily by vegetation and rocks. Females were observed through twelve different types of perches. With regard to perch height use, the CCA showed that females from PAC, LMJ, LMZ, SMR, CER, and CAH populations were correlated with height to nearest perch (HNP), while the rest of the females were not related to any perch use variable. On the other hand, the CCA showed that males from PAC, LMJ and CAH were characterized by microhabitats with higher vegetal coverage, while males from LMZ and CER used microhabitats composed of bare soil, but males from HUI and SMR populations used microhabitats composed chiefly of bare soil and rocks. With respect to perch height use, the CCA showed that males from PAC, LMJ, EZA, and LMZ were correlated with DNP, but the rest of the males were not correlated with any perch use variables. Males were observed in nine different perch types. Morphologically the males were larger than the females in all morphological variables analyzed. Moreover, in both sexes the SVL is positively correlated with all morphological variables, and although slopes and ordinate of the origin of all morphological variables were larger in males than females, the ANCOVAs indicated that there is no increase in the morphological variables with increasing SVL between sexes. Our results suggest that variation in habitat use and morphology among populations is an adaptive response (phenotypic plasticity) to the environmental conditions where these populations of S. grammicus occur. This article is protected by copyright. All rights reserved.

  16. Wound Myiasis due to Musca domestica (Diptera: Muscidae) in Persian Horned Viper, Pseudocerastes persicus (Squamata: Viperidae)

    PubMed Central

    Dehghani, R; Sedaghat, MM; Bidgoli, M Sabahi

    2012-01-01

    A case of myiasis due to Musca domestica describes in Pseudocerastes persicus for the first time. The snake was found in Bari Karafs, Kashan, Iran, with a lesion on its body. Fourteen live larvae of M. domestica removed from its wound. This is the first report of a new larval habitat of M. domestica. PMID:23293783

  17. Molecular phylogeny and historical biogeography of the Anatolian lizard Apathya (Squamata, Lacertidae).

    PubMed

    Kapli, Paschalia; Botoni, Dimitra; Ilgaz, Cetin; Kumlutaş, Yusuf; Avcı, Aziz; Rastegar-Pouyani, Nasrullah; Fathinia, Behzad; Lymberakis, Petros; Ahmadzadeh, Faraham; Poulakakis, Nikos

    2013-03-01

    Apathya is a lacertid genus occurring mainly in south-east Turkey and its adjacent regions (part of Iran and Iraq). So far two morphological species have been attributed to the genus; A. cappadocica (with five subspecies, A. c.cappadocica, A. c.muhtari, A. c.schmidtlerorum, A. c. urmiana and A. c.wolteri) and A.yassujica. The first species occupies most of the genus' distribution range, while A. yassujica is endemic of the Zagros Mountains. Here, we explored Apathya's taxonomy and investigated the evolutionary history of the species by employing phylogenetic and phylogeographic approaches and using both mitochondrial (mtDNA) and nuclear markers. The phylogenetic relationships and the genetic distances retrieved, revealed that Apathya is a highly variable genus, which parallels its high morphological variation. Such levels of morphological and genetic differentiation often exceed those between species of other Lacertini genera that are already treated as full species, suggesting the necessity for a taxonomic revision of Apathya. The phylogeographical scenario emerging from the genetic data suggests that the present distribution of the genus was determined by a combination of dispersal and vicariance events between Anatolia and Southwest Asia dating back to the Miocene and continuing up to the Pleistocene. Key geological events for the understanding of the phylogeography of the genus are the movement of the Arabian plate that led to the configuration of Middle East (orogenesis of the mountain ranges of Turkey and Iran) and the formation of Anatolian Diagonal.

  18. Comparing alignment methods for inferring the history of the new world lizard genus Mabuya (Squamata: Scincidae).

    PubMed

    Whiting, Alison S; Sites, Jack W; Pellegrino, Katia C M; Rodrigues, Miguel T

    2006-03-01

    The rapid increase in the ability to generate molecular data, and the focus on model-based methods for tree reconstruction have greatly advanced the use of phylogenetics in many fields. The recent flurry of new analytical techniques has focused almost solely on tree reconstruction, whereas alignment issues have received far less attention. In this paper, we use a diverse sampling of gene regions from lizards of the genus Mabuya to compare the impact, on phylogeny estimation, of new maximum likelihood alignment algorithms with more widely used methods. Sequences aligned under different optimality criteria are analyzed using partitioned Bayesian analysis with independent models and parameter settings for each gene region, and the most strongly supported phylogenetic hypothesis is then used to test the hypothesis of two colonizations of the New World by African scincid lizards. Our results show that the consistent use of model-based methods in both alignment and tree reconstruction leads to trees with more optimal likelihood scores than the use of independent criteria in alignment and tree reconstruction. We corroborate and extend earlier evidence for two independent colonizations of South America by scincid lizards. Relationships within South American Mabuya are found to be in need of taxonomic revision, specifically complexes under the names M. heathi, M. agilis, and M. bistriata (sensu, M.T. Rodrigues, Papeis Avulsos de Zoologia 41 (2000) 313).

  19. Two new species of Japalura (Squamata: Agamidae) from the Hengduan Mountain Range, China

    PubMed Central

    WANG, Kai; JIANG, Ke; ZOU, Da-Hu; YAN, Fang; ZOU, Da-Hu; Cameron, D.SILER; CHE, Jing

    2016-01-01

    Until recently, the agamid species, Japalura flaviceps, was recognized to have the widest geographic distribution among members of the genus occurring in China, from eastern Tibet to Shaanxi Province. However, recent studies restricted the distribution of J. flaviceps to the Dadu River valley only in northwestern Sichuan Province, suggesting that records of J. flaviceps outside the Dadu River valley likely represent undescribed diversity. During two herpetofaunal surveys in 2013 and 2015, eight and 12 specimens of lizards of the genus Japalura were collected from the upper Nujiang (=Salween) Valley in eastern Tibet, China, and upper Lancang (=Mekong) Valley in northwestern Yunnan, China, respectively. These specimens display a unique suite of diagnostic morphological characters. Our robust comparisons of phenotype reveal that these populations can be distinguished readily from J. flaviceps and all other recognized congeners. Herein, we describe the two Japalura lineages as new species, Japalura laeviventris sp. nov. and Japalura iadina sp. nov.. In addition, we provide updated conservation assessments for the new species as well as imperiled congeners according to the IUCN criteria for classification, discuss the importance of color patterns in the diagnosis and description of species in the genus Japalura, and discuss directions for future taxonomic studies of the group. PMID:26828033

  20. Biogeographical history and coalescent species delimitation of Pacific island skinks (Squamata: Scincidae: Emoia cyanura species group)

    USGS Publications Warehouse

    Klein, Elaine; Harris, Rebecca; Fisher, Robert N.; Reeder, Tod

    2016-01-01

    In contrast to the expectations of a stepping-stone model, E. cyanura and E. impar each exhibit the genetic signature of a rapid radiation during the mid to late Pleistocene, with evidence for newly identified lineages, mainly on western islands. Of these recovered lineages, we propose three to be elevated to species status. These findings expand our understanding of endemic Pacific biota, which are subject to conservation threats from human impacts and climate change.

  1. A new small karst-dwelling species of Cyrtodactylus (Reptilia: Squamata: Gekkonidae) from Java, Indonesia.

    PubMed

    Riyanto, Awal; Bauer, Aaron M; Yudha, Donan Satria

    2014-04-07

    A new small karst-dwelling species of the genus Cyrtodactylus is described from East Java and Special Province of Yogyakarta, Indonesia. Cyrtodactylus semiadii sp. nov. is a small species (SVL to 47.1 mm in females, 42.1 mm in males) distinguished from all other congeners by unique characters combination: short, robust, cylindrical tail, indistinct ventrolateral folds, absence of precloacal groove, absence of enlarged femoral scales, absence of precloacal and femoral pores and lack of enlarged median subcaudal scales. It is the third member of the genus recorded from Java. 

  2. Proteomic Profile of Mabuya sp. (Squamata: Scincidae) Ovary and Placenta During Gestation.

    PubMed

    Hernández-Díaz, Nathaly; Torres, Rodrigo; Ramírez-Pinilla, Martha Patricia

    2017-04-11

    Reptiles are one of the most diverse groups of vertebrates, providing an integrated system for comparative studies on metabolic, animal physiology, and developmental biology. However, the molecular data available are limited and only recently have started to call attention in the "omics" sciences. Mabuya sp. is a viviparous placentrotrophic skink with particular reproductive features, including microlecithal eggs, early luteolysis, prolonged gestation, and development of a highly specialized placenta. This placenta is responsible for respiratory exchange and the transference of all nutrients necessary for embryonic development. Our aim was to identify differentially expressed proteins in the ovary and placenta of Mabuya sp. during early, mid, and late gestation; their possible metabolic pathways; and biological processes. We carried out a comparative proteomic analysis during gestation in both tissues by sodium dodecyl sulfate polyacrylamide gel electrophoresis, two-dimensional gel electrophoresis, and matrix-assisted laser desorption/ionization. Differential protein expression in both tissues (Student's t-test P < 0.05) was related to several processes such as cell structure, cell movement, and energy. Proteins found in ovary are mainly associated with follicular development and its regulation. In the placenta, particularly during mid and late gestation, protein expression is involved in nutrient metabolism, transport, protein synthesis, and embryonic development. This work provides new insights about the proteins expressed and their physiological mechanisms in Mabuya sp. placenta and ovary during gestation.

  3. Two new species of Cyrtodactylus (Squamata: Gekkonidae) from the karst forest of Hoa Binh Province, Vietnam.

    PubMed

    Nguyen, Truong Quang; Le, Minh Duc; Pham, Anh Van; Ngo, Hai Ngoc; Hoang, Chung Van; Ziegler, Thomas

    2015-07-13

    We describe two new species of the genus Cyrtodactylus on the basis of a new reptile collection from the limestone karst forest of Hoa Binh Province, northwestern Vietnam. Cyrtodactylus otai sp. nov. from Hang Kia-Pa Co Nature Reserve and Cyrtodactylus bobrovi sp. nov. from Ngoc Son-Ngo Luong Nature Reserve can be distinguished from each other and from their congeners by their genetic distinction and morphological differences in number of precloacal pores, femoral scales, ventral scales, lamellae, subcaudals and dorsal tubercle arrangement, as well as in size and color pattern. In phylogenetic analyses, both new species are nested in a clade containing taxa from northwestern and northcentral Vietnam and northern Laos, i.e., C. bichnganae and C. cf. martini from northwestern Vietnam, C. puhuensis from northcentral Vietnam, and C. spelaeus, C. vilaphongi, and C. wayakonei from northern Laos.

  4. New species of Allopharynx (Digenea: Plagiorchiidae) and other helminths in Uranoscodon superciliosus (Squamata: Tropiduridae) from Amazonian Brazil.

    PubMed

    Bursey, Charles R; Goldberg, Stephen R; Vitt, Laurie J

    2005-12-01

    Allopharynx daileyi n. sp. (Digenea: Plagiorchiidae) from the small intestine of the tropidurid lizard Uranoscodon superciliosus from Amazonian Brazil is described and illustrated. Of the 11 currently recognized species of Allopharynx, we consider Allopharynx megorchis Simha, 1961 a synonym of Allopharynx mehrai (Gogate, 1935) Price 1938 and Allopharynx puertoricensis Acholonu, 1976 a synonym of Allopharynx riopedrensis Garcia-Diaz; thus, A. daileyi becomes the 10th species assigned to the genus. The trematode species Mesocoelium monas and 2 species of Nematoda, Africana chabaudi and Cosmocerca vrcibradici, were also present.

  5. Two new species of Pharyngodonidae (Nematoda: Oxyuroidea) and other nematodes in Agama caudospina (Squamata: Agamidae) from Kenya, Africa.

    PubMed

    Bursey, Charles R; Goldberg, Stephen R

    2005-06-01

    Parapharyngodon kenyaensis n. sp. and Thelandros samburuensis n. sp. (Nematoda: Pharyngodonidae) from the large intestine of the agamid lizard (Agama caudospina) are described and illustrated. Parapharyngodon kenyaensis n. sp. is the 41st species assigned to the genus, and it differs from other species in that genus by possessing 3 pairs of caudal papillae, cloacal lip adornment, and spicules of 112-120 microm in length. Thelandros samburuensis n. sp. is the 31st species assigned to the genus, and it differs from other species in that genus by possessing swollen posterior annulations, 6 caudal papillae, a smooth anterior cloacal lip, and spicules of 43-52 microm in length. In addition to the 2 new nematode species, Abbreviata ortleppi (Nematoda: Physalopteridae) and Strongyluris ornata (Nematoda: Heterakidae) were found.

  6. Two newly recognized species of Hemidactylus (Squamata, Gekkonidae) from the Arabian Peninsula and Sinai, Egypt.

    PubMed

    Smíd, Jiří; Moravec, Jiří; Kratochvíl, Lukáš; Gvoždík, Václav; Nasher, Abdul Karim; Busais, Salem M; Wilms, Thomas; Shobrak, Mohammed Y; Carranza, Salvador

    2013-01-01

    A recent molecular phylogeny of the Arid clade of the genus Hemidactylus revealed that the recently described H. saba and two unnamed Hemidactylus species from Sinai, Saudi Arabia and Yemen form a well-supported monophyletic group within the Arabian radiation of the genus. The name 'Hemidactylus saba species group' is suggested for this clade. According to the results of morphological comparisons and the molecular analyses using two mitochondrial (12S and cytb) and four nuclear (cmos, mc1r, rag1, rag2) genes, the name Hemidactylus granosus Heyden, 1827 is resurrected from the synonymy of H. turcicus for the Sinai and Saudi Arabian species. The third species of this group from Yemen is described formally as a new species H. ulii sp. n. The phylogenetic relationships of the members of 'Hemidactylus saba species group' are evaluated and the distribution and ecology of individual species are discussed.

  7. Escape tactics and effects of perch height and habituation on flight initiation distance in two Jamaican anoles (Squamata: polychrotidae).

    PubMed

    Cooper, William E

    2010-12-01

    Escape by Anolis lizards is influenced by microhabitats and fight initiation distance increases with predation risk. Differences in microhabitat use among ecomorphs affect escape behavior, but only two studies have reported ecomorphological differences in flight initiation distance among Greater Antillean species. I studied effects of predation risk and microhabitats on escape behavior by conducting field experiments using two species of anoles, Anolis lineatopus and A. grahami, on the campus of the University of the West Indies at Mona, Jamaica. Because ecomorphological variation of anoles has evolved independently within each island of the Greater Antilles, but relationships between ecomorphs and escape behaviors are poorly known, I characterized microhabitat use and escape tactics, and determined relationships between flight initiation distance and two risk factors, habituation to human presence and perch height, in Anolis lineatopus, a trunk-ground anole and A. grahami, a trunk-crown anole. Sample sizes for A. lineatopus and A. grahami were 214 and 93, for microhabitat use and escape destinations, 74 and 34 for human presence and 125 and 34 for perch height. The two species occurred in similar microhabitats and exhibited similar escape tactics, but exhibited key differences expected for their ecomorphs. Both species were sighted frequently on the ground and on trees, but A. lineatopus were more frequently on ground and were perched lower than A. grahami. Both species escaped from ground to trees and when on trees hid on far sides and escaped without changing climbing direction with equal frequency. The frequency of fleeing upward was greater for A. grahami than A. lineatopus. Both species exhibited habituation by having shorter flight initiation distances in areas with more frequent exposure to people. In both species flight initiation distance increased as perch height decreased because, lizards had to climb farther to be out of reach when perched lower. The relationship between flight initiation distance and perch height may apply to other anole ecomorphs that flee upward when low perched on trees.

  8. Treerunners, cryptic lizards of the Plica plica group (Squamata, Sauria, Tropiduridae) of northern South America.

    PubMed

    Murphy, John C; Jowers, Michael J

    2013-01-01

    The arboreal, Neotropical lizard Plica plica (Linnaeus, 1758) has been long considered a widespread species with a distribution east of the Andes. A preliminary examination of 101 specimens from about 28 locations mostly north of the Amazon suggests that Plica plica is a cryptic species complex with taxa that can be distinguished on the basis of the number of scale rows at mid-body; the arrangement, shape and ornamentation of scales on the snout; the number of lamellae on the fourth toe; the number of subocular plates; as well as other commonly used external morphological traits. The allopatric species discussed here are concordant with northern South American geography. Plica plica (Linnaeus, 1758) is associated with the Guiana Shield (Suriname, Guyana and Venezuela). A second species, P. caribeana sp. n. is associated with the Caribbean Coastal Range of Venezuela including Trinidad and Tobago. A third, distinctive species, P. rayi sp. n. is associated with the middle Orinoco at the eastern edge of the Guiana Shield. Two other species, P. kathleenae sp. n. and P. medemi sp. n., each based upon a single specimen, one from the Sierra Acarai Mountains of Guyana, and the other from southern Meta, Colombia are described. In addition to morphological analyses, we sequenced 12S and 16S rDNA gene fragments from one Plica plica from Trinidad to assess its relationship and taxonomy to other mainland Plica cf. plica. The results suggest Plica caribeana sp. n. likely diverged prior to the separation of Trinidad from northern Venezuela. Isolation in the Caribbean Coastal Range during its rapid uplift in the late Miocene, combined with a marine incursion into northern Venezuela may have contributed to their genetic divergence from other populations.

  9. Molecular phylogenetics and biogeography of the Neotropical skink genus Mabuya Fitzinger (Squamata: Scincidae) with emphasis on Colombian populations.

    PubMed

    Pinto-Sánchez, Nelsy Rocío; Calderón-Espinosa, Martha L; Miralles, Aurélien; Crawford, Andrew J; Ramírez-Pinilla, Martha Patricia

    2015-12-01

    Understanding the phylogenetic and geographical history of Neotropical lineages requires having adequate geographic and taxonomic sampling across the region. However, Colombia has remained a geographical gap in many studies of Neotropical diversity. Here we present a study of Neotropical skinks of the genus Mabuya, reptiles that are difficult to identify or delimit due to their conservative morphology. The goal of the present study is to propose phylogenetic and biogeographic hypotheses of Mabuya including samples from the previously under-studied territory of Colombia, and address relevant biogeographic and taxonomic issues. We combined molecular and morphological data sampled densely by us within Colombia with published data representing broad sampling across the Neotropical realm, including DNA sequence data from two mitochondrial (12S rRNA and cytochrome b) and three nuclear genes (Rag2, NGFB and R35). To evaluate species boundaries we employed a general mixed Yule-coalescent (GMYC) model applied to the mitochondrial data set. Our results suggest that the diversity of Mabuya within Colombia is higher than previously recognized, and includes lineages from Central America and from eastern and southern South America. The genus appears to have originated in eastern South America in the Early Miocene, with subsequent expansions into Central America and the Caribbean in the Late Miocene, including at least six oceanic dispersal events to Caribbean Islands. We identified at least four new candidate species for Colombia and two species that were not previously reported in Colombia. The populations of northeastern Colombia can be assigned to M. zuliae, while specimens from Orinoquia and the eastern foothills of the Cordillera Oriental of Colombia correspond to M. altamazonica. The validity of seven species of Mabuya sensu lato was not supported due to a combination of three factors: (1) non-monophyly, (2) <75% likelihood bootstrap support and <0.95 Bayesian posterior probability, and (3) GMYC analysis collapsing named species. Finally, we suggest that Mabuya sensu stricto may be regarded as a diverse monophyletic genus, widely distributed throughout the Neotropics.

  10. Seasonal variations in behaviour of thermoregulation in juveniles and adults Liolaemus lutzae (Squamata, Liolaemidae) in a remnant of Brazilian restinga.

    PubMed

    Maia-Carneiro, Thiago; Rocha, Carlos Frederico Duarte

    2013-11-01

    Adaptations of lizards inhabiting hot arid environments should include mechanisms of behavioural thermoregulation. In contrast, in environments with lower temperatures lizards tend to behave as thermoconformers. Herein we aim to infer thermoregulatory behaviours exhibited by Liolaemus lutzae (a lizard species endemic to restingas in the coast of the state of Rio de Janeiro, Brazil) in two different seasonal thermal environments. In the dry season, the body temperatures (Tb) of the lizards were higher than air temperature (Ta) and similar to substrate temperature (Ts), suggesting thermoconformer thermoregulatory behaviour using Ts. During the rainy season, the higher percentage of negative values of ΔTs (=Tb-Ts) and ΔTa (=Tb-Ta) and the tendency for lower Tb compared to Ts suggest a more active behavioural thermoregulation in that season. The ΔTs was higher for juveniles in the rainy season, suggesting that youngest lizards tended to thermoregulate more actively regarding to Ts than adults. L. lutzae probably survives under high Ts due to the behaviour of the individuals sheltering inside burrows or under detritus and burying themselves into the sand. This behavioural flexibility may potentially reduce variations in Tb of active lizards in changing thermal environments both during the daily cycle and between seasons.

  11. Diet of the lizard Liolaemus occipitalis in the coastal sand dunes of southern Brazil (Squamata-Liolaemidae).

    PubMed

    Verrastro, L; Ely, I

    2015-05-01

    Knowledge of a species' diet provides important information on adaptation and the relationship between the organism and its environment. The genus Liolaemus occurs in the southern region of South America and is an excellent model to investigate the adaptive processes of vertebrate ecology in ecosystems of this region of the world. Liolaemus occipitalis is an endangered species that inhabits the coastal sand dunes of southern Brazil. This species is the most abundant vertebrate in this environment, and it presents unique adaptation characteristics to the restinga environment. The present study analyzed this lizard's diet to verify similarities or differences between this species and other species of the same genus. Specimens were collected monthly from January 1996 to December 1997. The number of items, frequency of occurrence and volume of each prey taxon were determined. Arthropods were identified to the order level, and plant material was identified as flower, fruit, seed and leaves. Variations in the diet of males and females, adults and juveniles and seasons were also analyzed. The data indicate that Liolaemus occipitalis is a generalist, "sit-and-wait" or ambush predator as well as omnivorous, feeding on both arthropods and plant material. Significant ontogenetic differences were verified. Juveniles are more carnivorous, and the intake of plant material increases with size and age. Seasonal differences in diet composition were also observed. In the spring, arthropod and plant materials were more diversified and, therefore, consumed more often.

  12. Treerunners, cryptic lizards of the Plica plica group (Squamata, Sauria, Tropiduridae) of northern South America

    PubMed Central

    Murphy, John C.; Jowers, Michael J.

    2013-01-01

    Abstract The arboreal, Neotropical lizard Plica plica (Linnaeus, 1758) has been long considered a widespread species with a distribution east of the Andes. A preliminary examination of 101 specimens from about 28 locations mostly north of the Amazon suggests that Plica plica is a cryptic species complex with taxa that can be distinguished on the basis of the number of scale rows at mid-body; the arrangement, shape and ornamentation of scales on the snout; the number of lamellae on the fourth toe; the number of subocular plates; as well as other commonly used external morphological traits. The allopatric species discussed here are concordant with northern South American geography. Plica plica (Linnaeus, 1758) is associated with the Guiana Shield (Suriname, Guyana and Venezuela). A second species, P. caribeana sp. n. is associated with the Caribbean Coastal Range of Venezuela including Trinidad and Tobago. A third, distinctive species, P. rayi sp. n. is associated with the middle Orinoco at the eastern edge of the Guiana Shield. Two other species, P. kathleenae sp. n. and P. medemi sp. n., each based upon a single specimen, one from the Sierra Acarai Mountains of Guyana, and the other from southern Meta, Colombia are described. In addition to morphological analyses, we sequenced 12S and 16S rDNA gene fragments from one Plica plica from Trinidad to assess its relationship and taxonomy to other mainland Plica cf. plica. The results suggest Plica caribeana sp. n. likely diverged prior to the separation of Trinidad from northern Venezuela. Isolation in the Caribbean Coastal Range during its rapid uplift in the late Miocene, combined with a marine incursion into northern Venezuela may have contributed to their genetic divergence from other populations. PMID:24363569

  13. A new forest-dwelling Bent-toed Gecko (Squamata: Gekkonidae: Cyrtodactylus) from Doi Inthanon, Chiang Mai Province, northern Thailand.

    PubMed

    Kunya, Kirati; Sumontha, Montri; Panitvong, Nonn; Dongkumfu, Wuttipong; Sirisamphan, Thana; Pauwels, Olivier S G

    2015-01-14

    We describe a new forest-dwelling Cyrtodactylus from Doi Inthanon, Chiang Mai Province, northern Thailand. Cyrtodactylus inthanon sp. nov. is characterized by a maximum known SVL of 87.3 mm; 18 to 20 longitudinal rows of dorsal tubercles; a continuous series of 34 to 37 enlarged femoro-precloacal scales, including four to six pitted (female) or pore-bearing (male) scales on each femur separated by a diastema from five pitted (females) or pore-bearing (male) precloacal scales; no precloacal groove or depression; transversely enlarged subcaudal scales; and three to five irregular beige dorsal bands between limb insertions. The discovery of a new reptile endemic to Doi Inthanon reinforces the high importance of this mountain in terms of biodiversity conservation.

  14. Lizard Wears Shades. A Spectacled Sphenomorphus (Squamata: Scincidae), from the Sacred Forests of Mawphlang, Meghalaya, North-east India.

    PubMed

    Datta-Roy, Aniruddha; Das, Indraneil; Bauer, Aaron M; Tron, Ronald K Lyngdoh; Karanth, Praveen

    2013-01-01

    A new species of lygosomatine scincid lizard is described from the sacred forests of Mawphlang, in Meghalaya, northeastern India. Sphenomorphus apalpebratus sp. nov. possesses a spectacle or brille, an unusual feature within the Scincidae, and a first for the paraphyletic genus Sphenomorphus. The new species is compared with other members of the genus to which it is here assigned, as well as to members of the lygosomatine genera Lipinia and Scincella from mainland India, the Andaman and Nicobar Islands, and southeast Asia, to which it also bears resemblance. The new taxon is diagnosable in exhibiting the following combination of characters: small body size (SVL to 42.0 mm); moveable eyelids absent; auricular opening scaleless, situated in a shallow depression; dorsal scales show a line of demarcation along posterior edge of ventral pes; midbody scale rows 27-28; longitudinal scale rows between parietals and base of tail 62-64; lamellae under toe IV 8-9; supraoculars five; supralabials 5-6; infralabials 4-5; subcaudals 92; and dorsum golden brown, except at dorsal margin of lateral line, which is lighter, with four faintly spotted lines, two along each side of vertebral row of scales, that extend to tail base. The new species differs from its congeners in the lack of moveable eyelids, a character shared with several distantly related scincid genera.

  15. Molecular phylogenetic relationships of the Liolaemus rothi complex and a new species of lizard from Auca Mahuida Volcano (Squamata: Liolaemini).

    PubMed

    Avila, Luciano Javier; Olave, Melisa; Perez, Cristian Hernan Fulvio; Perez, Daniel Roberto; Morando, Mariana

    2013-01-21

    A new species of lizard of the genus Liolaemus from Neuquén Province, western Argentina, is described. The new species is a member of the Liolaemus rothi species complex, and mitochondrial and nuclear molecular data show it as sister taxon of the clade composed of (L. hermannunezi (L. tromen + L. loboi)), differing in size, squamation, coloration, and sexual dimorphism from the other species of this group. Liolaemus sitesi sp. nov. has a dark body coloration with series of notched blotches on the dorsum, with bright spots, and a very iridescent yellow-green coloration in natural light. Liolaemus sitesi sp. nov. is found only in the Auca Mahuida volcano and is terrestrial, dwelling on the stony slopes with sandy soil between 1300 m and the volcano summit.

  16. Revision of the genus Lepidoblepharis (Reptilia: Squamata: Sphaerodactylidae) in Central America, with the description of three new species.

    PubMed

    Batista, Abel; Ponce, Marcos; Vesely, Milan; Mebert, Konrad; Hertz, Andreas; Köhler, Gunther; Carrizo, Arcadio; Lotzkat, Sebastian

    2015-07-31

    Based on morphological and molecular data, we describe three new species of the genus Lepidoblepharis with granular dorsals from Panama (Lepidoblepharis emberawoundule sp. nov., Lepidoblepharis rufigularis sp. nov., and Lepidoblepharis victormartinezi sp. nov.). The results of our molecular analyses confirm the existence of five deeply differentiated genealogical lineages among Panamanian Lepidoblepharis. We present detailed descriptions of their morphology, including some new valuable scalation characters (ventral and subfemoral escutcheon) and hemipenes, as well as comparisons with the other two species of the genus known to occur in Panama (L. sanctaemartae and L. xanthostigma) and their South American congeners. Last, we provide an updated identification key for the genus Lepidoblepharis in Central America.

  17. Two new species of Andean gymnophthalmid lizards of the genus Euspondylus (Reptilia, Squamata) from central and southern Peru

    PubMed Central

    Chávez, Germán; Siu-Ting, Karen; Duran, Vilma; Venegas, Pablo J

    2011-01-01

    Abstract Two new species of lizards assigned to the genus Euspondylus from the montane forests of the Peruvian Andes in the Pasco Department (central Peru) and Ayacucho Department (southern Peru) both at elevations of 2550 and 3450 m, respectively, are described. The new species are distinguishable from all other Peruvian and Ecuadorian species of Euspondylus by a unique combination of morphometric, scalation and color pattern characteristics. Natural history data for the new species and for Euspondylus spinalis are also provided. PMID:21852931

  18. Off the scale: a new species of fish-scale gecko (Squamata: Gekkonidae: Geckolepis) with exceptionally large scales.

    PubMed

    Scherz, Mark D; Daza, Juan D; Köhler, Jörn; Vences, Miguel; Glaw, Frank

    2017-01-01

    The gecko genus Geckolepis, endemic to Madagascar and the Comoro archipelago, is taxonomically challenging. One reason is its members ability to autotomize a large portion of their scales when grasped or touched, most likely to escape predation. Based on an integrative taxonomic approach including external morphology, morphometrics, genetics, pholidosis, and osteology, we here describe the first new species from this genus in 75 years: Geckolepis megalepissp. nov. from the limestone karst of Ankarana in northern Madagascar. The new species has the largest known body scales of any gecko (both relatively and absolutely), which come off with exceptional ease. We provide a detailed description of the skeleton of the genus Geckolepis based on micro-Computed Tomography (micro-CT) analysis of the new species, the holotype of G. maculata, the recently resurrected G. humbloti, and a specimen belonging to an operational taxonomic unit (OTU) recently suggested to represent G. maculata. Geckolepis is characterized by highly mineralized, imbricated scales, paired frontals, and unfused subolfactory processes of the frontals, among other features. We identify diagnostic characters in the osteology of these geckos that help define our new species and show that the OTU assigned to G. maculata is probably not conspecific with it, leaving the taxonomic identity of this species unclear. We discuss possible reasons for the extremely enlarged scales of G. megalepis in the context of an anti-predator defence mechanism, and the future of Geckolepis taxonomy.

  19. Combined next-generation sequencing and morphology reveal fine-scale speciation in Crocodile Skinks (Squamata: Scincidae: Tribolonotus).

    PubMed

    Rittmeyer, Eric N; Austin, Christopher C

    2015-01-01

    Next-generation sequencing has vast potential to revolutionize the fields of phylogenetics and population genetics through its ability to collect genomic scale data sets of thousands of orthologous loci. Despite this potential, other types of data (e.g. morphology, ecology) remain important, particularly for studies endeavouring to delimit species. Here, we integrate next-generation sequencing with morphology to examine divergence between populations of Tribolonotus pseudoponceleti on the islands of Buka and Bougainville in the Solomon Archipelago. We used the Ion Torrent PGM to collect over 648 Mbp of sequence data for 12 samples, representing 1526 loci recovered from all samples, and 3342 were recovered from at least six samples. Genetic structure analyses strongly support the distinctiveness of these two populations, and Bayes factor delimitations decisively select speciation between Buka and Bougainville. Principal components and discriminant function analyses reveal concordant morphological divergence. Finally, demographic analyses via diffusion approximation and approximate Bayesian computation prefer a complex model of mid-Pleistocene divergence with migration, and a later decrease or cessation of migration and population size shift, suggesting a scenario in which migration was enabled by Pleistocene merging of these two islands, and limited when isolated by higher sea levels. Further analysis of four Sanger sequenced loci in IMa2 had limited power to distinguish among models including and excluding migration, but resulted in similar population size and divergence time estimates, although with much broader confidence intervals. This study represents a framework for how next-generation sequencing and morphological data can be combined and leveraged towards validating putative species and testing demographic scenarios for speciation.

  20. The atlas-axis complex in chamaeleonids (Squamata: Chamaeleonidae), with description of a new anatomical structure of the skull.

    PubMed

    Čerňanský, Andrej; Boistel, Renaud; Fernandez, Vincent; Tafforeau, Paul; Nicolas, Le Noir; Herrel, Anthony

    2014-03-01

    The comparative vertebral morphology of different chamaeleonid genera has been generally neglected and some aspects such as the comparative anatomy of the neck region remain poorly known. The atlas and axis of all chamaeleonid genera (Brookesia, Rieppeleon, Archaius, Rhampholeon, Nadzikambia, Bradypodion, Chamaeleo, Calumma, Furcifer, Kinyongia, and Trioceros) are studied here. Considerable morphological differences are revealed. Additionally, some taxa exhibit sexual dimorphism in the atlas and axis. An extremely long, divided posterodorsal process is present in males of the Trioceros johnstoni + Trioceros jacksonii clade. The solid and well-developed morphology of the posterodorsal process in males of this taxon could reflect its competitive behavior-males fight with their horns and attempt to dislodge one another from branches during encounters. An additional area of insertion for the cervical musculature may indicate an incremental cervical musculature mass and cross sectional area that can add extra support and stability to the head and assist during combat involving lateral pushing. This character is not present in females. Heterochronic processes have played a role in the evolution of chamaeleonids, as evidenced in many characters of the atlas-axis complex. A new hypothesis of an anterior shifting of synapophyses of the axis is erected and a new derived anatomical structure of the parietal of Chamaeleo calyptratus is described (the processus parietalis inferior). The presence of the processus parietalis inferior is associated with the evolution of the dorsally elevated parietal crest.

  1. A fossil Diploglossus (Squamata, Anguidae) lizard from Basse-Terre and Grande-Terre Islands (Guadeloupe, French West Indies)

    PubMed Central

    Bochaton, Corentin; Boistel, Renaud; Casagrande, Fabrice; Grouard, Sandrine; Bailon, Salvador

    2016-01-01

    Today, Diploglossine lizards (Anguidae) are common on the Greater Antillean Islands (West Indies), where they are represented by many endemic species. However these lizards are very rare on the Lesser Antillean Islands, where they are only represented by a single species, the Montserrat galliwasp (Diploglossus montisserrati). Here, we show that diploglossine lizards were present in the past on other Lesser Antillean islands, by reporting the discovery of Anguidae fossil remains in two Amerindian archaeological deposits and in a modern deposit. These remains are compared to skeletons of extant diploglossine lizards, including D. montisserrati, using X-ray microtomography of the type specimen of this critically endangered lizard. We also conducted a histological study of the osteoderms in order to estimate the putative age of the specimen. Our results show that the fossil specimens correspond to a member of the Diploglossus genus presenting strong similarities, but also minor morphological differences with D. montisserrati, although we postulate that these differences are not sufficient to warrant the description of a new species. These specimens, identified as Diploglossus sp., provide a new comparison point for the study of fossil diploglossine lizards and reflect the historical 17th century mentions of anguid lizards, which had not been observed since. PMID:27354326

  2. An endemic new species of Ameiva (Squamata: Teiidae) from an isolated dry   forest in southern Peru.

    PubMed

    Landauro, Caroll Z; García-Bravo, Antonio; Venegas, Pablo J

    2015-04-10

    We describe a new species of Ameiva from an interandean dry forest in central-southern Peru. Ameiva reticulata sp. nov. represents the fifth species in the genus known to occur in Peru. The new species is similar to the species of the A. ameiva complex such as A. ameiva, A. atrigularis, A. pantherina, and A. praesignis, and is distinguished from these by a smaller size, a lower count of dorsal scales along the middorsal line and scales across the midbody, and by the gular coloration.

  3. A new species of iguanid lizard, genus Stenocercus (Squamata, Iguania), from the Central Andes in Peru.

    PubMed

    Venegas, Pablo J; Echevarría, Lourdes Y; García-Burneo, Karla; Koch, Claudia

    2016-12-04

    We describe a new species of Stenocercus from the montane forest of the right margin of the Marañón river in the northern portion of the Central Andes in northern Peru (Amazonas and La Libertad departments), at elevations ranging from 2300 to 3035 m. Stenocercus omari sp. nov. differs from other Stenocercus species, with the exception of S. amydrorhytus, S. chrysopygus, S. cupreus, S. johaberfellneri, S. latebrosus, S. melanopygus, S. modestus, S. ornatissimus, S. orientalis, and S. stigmosus, by having granular scales on the posterior surfaces of thighs, a conspicuous antehumeral fold and by lacking a vertebral crest. However, Stenocercus omari sp. nov. is easily distinguished from the aforementioned species, except S. orientalis, by the presence of prominently keeled dorsal head scales. The new species differs from S. orientalis by lacking a prominent oblique neck fold and by having a distinct deep postfemoral mite pocket.

  4. Two new species of Andean gymnophthalmid lizards of the genus Euspondylus (Reptilia, Squamata) from central and southern Peru.

    PubMed

    Chávez, Germán; Siu-Ting, Karen; Duran, Vilma; Venegas, Pablo J

    2011-01-01

    Two new species of lizards assigned to the genus Euspondylus from the montane forests of the Peruvian Andes in the Pasco Department (central Peru) and Ayacucho Department (southern Peru) both at elevations of 2550 and 3450 m, respectively, are described. The new species are distinguishable from all other Peruvian and Ecuadorian species of Euspondylus by a unique combination of morphometric, scalation and color pattern characteristics. Natural history data for the new species and for Euspondylus spinalis are also provided.

  5. Vulnerability to climate warming of Liolaemus pictus (Squamata, Liolaemidae), a lizard from the cold temperate climate in Patagonia, Argentina.

    PubMed

    Kubisch, Erika Leticia; Fernández, Jimena Beatriz; Ibargüengoytía, Nora Ruth

    2016-02-01

    The vulnerability of populations and species to global warming depends not only on the environmental temperatures, but also on the behavioral and physiological abilities to respond to these changes. In this sense, the knowledge of an organism's sensitivity to temperature variation is essential to predict potential responses to climate warming. In particular, it is interesting to know how close species are to their thermal limits in nature and whether physiological plasticity is a potential short-term response to warming climates. We exposed Liolaemus pictus lizards, from northern Patagonia, to either 21 or 31 °C for 30 days to compare the effects of these treatments on thermal sensitivity in 1 and 0.2 m runs, preferred body temperature (T pref), panting threshold (T pant), and critical minimum temperature (CTMin). Furthermore, we measured the availability of thermal microenvironments (operative temperatures; T e) to measure how close L. pictus is, in nature, to its optimal locomotor performance (T o) and thermal limits. L. pictus showed limited physiological plasticity, since the acclimation temperature (21 and 31 °C) did not affect the locomotor performance nor did it affect T pref, the T pant, or the CTMin. The mean T e was close to T o and was 17 °C lower than the CTMax. The results suggest that L. pictus, in a climate change scenario, could be vulnerable to the predicted temperature increment, as this species currently lives in an environment with temperatures close to their highest locomotor temperature threshold, and because they showed limited acclimation capacity to adjust to new thermal conditions by physiological plasticity. Nevertheless, L. pictus can run at 80 % or faster of its maximum speed across a wide range of temperatures near T o, an ability which would attenuate the impact of global warming.

  6. Photographic evidence of interspecies mating in geckos of the Lepidodactylus lugubris unisexual-bisexual complex (Squamata: Gekkonidae)

    USGS Publications Warehouse

    Buden, Donald W.; Cianchini, Carlos; Taborosi, Danko; Fisher, Robert N.; Bauer, Aaron; Ineich, Ivan

    2014-01-01

    An interspecies mating between unisexual Lepidodactylus lugubris and a male of the bisexual Lepidodactylus moestus was photographed by Carlos Cianchini on Kosrae [Island], FSM, at 18:15 h on 22 August 2013 (Figure 1). The mating pair was on a window frame inside a house at Pukusruk Wan village (05°21'01" N, 163°00'41" E, elev. 28 m a.s.l.) on the northeastern side of the island. This is the first direct evidence of mating between these two species.

  7. In the shadows: Phylogenomics and coalescent species delimitation unveil cryptic diversity in a Cerrado endemic lizard (Squamata: Tropidurus).

    PubMed

    Domingos, Fabricius M C B; Colli, Guarino R; Lemmon, Alan; Lemmon, Emily Moriarty; Beheregaray, Luciano B

    2017-02-01

    The recognition of cryptic diversity within geographically widespread species is gradually becoming a trend in the highly speciose Neotropical biomes. The statistical methods to recognise such cryptic lineages are rapidly advancing, but have rarely been applied to genomic-scale datasets. Herein, we used phylogenomic data to investigate phylogenetic history and cryptic diversity within Tropidurus itambere, a lizard endemic to the Cerrado biodiversity hotspot. We applied a series of phylogenetic methods to reconstruct evolutionary relationships and a coalescent Bayesian species delimitation approach (BPP) to clarify species limits. The BPP results suggest that the widespread nominal taxon comprises a complex of 5 highly supported and geographically structured cryptic species. We highlight and discuss the different topological patterns recovered by concatenated and coalescent species tree methods for these closely related lineages. Finally, we suggest that the existence of cryptic lineages in the Cerrado is much more common than traditionally thought, highlighting the value of using NGS data and coalescent techniques to investigate patterns of species diversity.

  8. Molecular phylogeny of Panaspis and Afroablepharus skinks (Squamata: Scincidae) in the savannas of sub-Saharan Africa.

    PubMed

    Medina, Maria F; Bauer, Aaron M; Branch, William R; Schmitz, Andreas; Conradie, Werner; Nagy, Zoltán T; Hibbitts, Toby J; Ernst, Raffael; Portik, Daniel M; Nielsen, Stuart V; Colston, Timothy J; Kusamba, Chifundera; Behangana, Mathias; Rödel, Mark-Oliver; Greenbaum, Eli

    2016-07-01

    African snake-eyed skinks are relatively small lizards of the genera Panaspis and Afroablepharus. Species allocation of these genera frequently changed during the 20th century based on morphology, ecology, and biogeography. Members of these genera occur primarily in savanna habitats throughout sub-Saharan Africa and include species whose highly conserved morphology poses challenges for taxonomic studies. We sequenced two mitochondrial (16S and cyt b) and two nuclear genes (PDC and RAG1) from 76 Panaspis and Afroablepharus samples from across eastern, central, and southern Africa. Concatenated gene-tree and divergence-dating analyses were conducted to infer phylogenies and biogeographic patterns. Molecular data sets revealed several cryptic lineages, with most radiations occurring during the mid-Miocene to Pliocene. We infer that rifting processes (including the formation of the East African Rift System) and climatic oscillations contributed to the expansion and contraction of savannas, and caused cladogenesis in snake-eyed skinks. Species in Panaspis and Afroablepharus used in this study, including type species for both genera, formed a monophyletic group. As a result, the latter genus should be synonymized with the former, which has priority. Conservatively, we continue to include the West African species P. breviceps and P. togoensis within an expanded Panaspis, but note that they occur in relatively divergent clades, and their taxonomic status may change with improved taxon sampling. Divergence estimates and cryptic speciation patterns of snake-eyed skinks were consistent with previous studies of other savanna vertebrate lineages from the same areas examined in this study.

  9. Evolution around the Red Sea: Systematics and biogeography of the agamid genus Pseudotrapelus (Squamata: Agamidae) from North Africa and Arabia.

    PubMed

    Tamar, Karin; Scholz, Sebastian; Crochet, Pierre-André; Geniez, Philippe; Meiri, Shai; Schmitz, Andreas; Wilms, Thomas; Carranza, Salvador

    2016-04-01

    Since the Oligocene, regions adjacent to the Red Sea have experienced major environmental changes, from tectonic movements and continuous geological activity to shifting climatic conditions. The effect of these events on the distribution and diversity of the regional biota is still poorly understood. Agamid members of the genus Pseudotrapelus are diurnal, arid-adapted lizards distributed around the Red Sea from north-eastern Africa, across the mountains and rocky plateaus of the Sinai and Arabian Peninsulas northwards to Syria. Despite recent taxonomic work and the interest in the group as a model for studying biogeographic and diversity patterns of the arid areas of North Africa and Arabia, its taxonomy is poorly understood and a comprehensive phylogeny is still lacking. In this study, we analyzed 92 Pseudotrapelus specimens from across the entire distribution range of the genus. We included all known species and subspecies, and sequenced them for mitochondrial (16S, ND4 and tRNAs) and nuclear (MC1R, c-mos) markers. This enabled us to obtain the first time-calibrated molecular phylogeny of the genus, using gene trees, species trees and coalescent-based methods for species delimitation. Our results revealed Pseudotrapelus as a monophyletic genus comprised of two major clades and six independently evolving lineages. These lineages correspond to the five currently recognized species and a sixth lineage relating to the synonymized P. neumanni. The subspecific validity of P. sinaitus werneri needs further assessment as it does not form a distinct cluster relative to P. s. sinaitus. The onset of Pseudotrapelus diversification is estimated to have occurred in Arabia during the late Miocene. Radiation has likely resulted from vicariance and dispersal events due to the continued geological instability, sea level fluctuations and climatic changes within the region.

  10. A large and unusually colored new snake species of the genus Tantilla (Squamata; Colubridae) from the Peruvian Andes.

    PubMed

    Koch, Claudia; Venegas, Pablo J

    2016-01-01

    A new colubrid species of the genus Tantilla from the dry forest of the northern Peruvian Andes is described on the basis of two specimens, which exhibit a conspicuous sexual dimorphism. Tantilla tjiasmantoi sp. nov. represents the third species of the genus in Peru. The new species is easily distinguished from its congeners by the combination of scalation characteristics and the unusual transversely-banded color pattern on the dorsum. A detailed description of the skull morphology of the new species is given based on micro-computed tomography images. The habitat of this new species is gravely threatened due to human interventions. Conservation efforts are urgently needed in the inter-Andean valley of the Maranon River.

  11. Early stages of divergence: phylogeography, climate modeling, and morphological differentiation in the South American lizard Liolaemus petrophilus (Squamata: Liolaemidae)

    PubMed Central

    Fontanella, Frank M; Feltrin, Natalia; Avila, Luciano J; Sites, Jack W; Morando, Mariana

    2012-01-01

    This study examines the phylogeographic structure within the Patagonian lizard Liolaemus petrophilus and tests for patterns of between-clade morphological divergence and sexual dimorphism, as well as demographic and niche changes associated with Pleistocene climate changes. We inferred intraspecific relationships, tested hypotheses for historical patterns of population expansion, and incorporated ecological niche modeling (ENM) with standard morphological and geometric morphometric analyses to examine between-clade divergence as indirect evidence for adaptation to different niches. The two inferred haploclades diverged during the early Pleistocene with the Southern clade depicting the genetic signature of a recent population increase associated with expanding niche envelope, whereas the Northern clade shows stable populations in a shrinking niche envelope. The combination of molecular evidence for postisolation demographic change and ENM, suggest that the two haploclades have responded differently to Pleistocene climatic events. PMID:22837827

  12. Off the scale: a new species of fish-scale gecko (Squamata: Gekkonidae: Geckolepis) with exceptionally large scales

    PubMed Central

    Daza, Juan D.; Köhler, Jörn; Vences, Miguel; Glaw, Frank

    2017-01-01

    The gecko genus Geckolepis, endemic to Madagascar and the Comoro archipelago, is taxonomically challenging. One reason is its members ability to autotomize a large portion of their scales when grasped or touched, most likely to escape predation. Based on an integrative taxonomic approach including external morphology, morphometrics, genetics, pholidosis, and osteology, we here describe the first new species from this genus in 75 years: Geckolepis megalepis sp. nov. from the limestone karst of Ankarana in northern Madagascar. The new species has the largest known body scales of any gecko (both relatively and absolutely), which come off with exceptional ease. We provide a detailed description of the skeleton of the genus Geckolepis based on micro-Computed Tomography (micro-CT) analysis of the new species, the holotype of G. maculata, the recently resurrected G. humbloti, and a specimen belonging to an operational taxonomic unit (OTU) recently suggested to represent G. maculata. Geckolepis is characterized by highly mineralized, imbricated scales, paired frontals, and unfused subolfactory processes of the frontals, among other features. We identify diagnostic characters in the osteology of these geckos that help define our new species and show that the OTU assigned to G. maculata is probably not conspecific with it, leaving the taxonomic identity of this species unclear. We discuss possible reasons for the extremely enlarged scales of G. megalepis in the context of an anti-predator defence mechanism, and the future of Geckolepis taxonomy. PMID:28194313

  13. [Home range of Aspidoscelis cozumela (Squamata: Teiidae): a parthenogenetic lizard microendemic to Cozumel Island, México].

    PubMed

    Hernández-Gallegos, Oswaldo; López-Moreno, Ana Esthela; Méndez-Sánchez, José Fernando; Rheubert, Justin Lloyd; Méndez-de la Cruz, Fausto Roberto

    2015-09-01

    Home range is defined as the area within which an individual moves to acquire resources necessary to increase their fitness and may vary inter and intra-specifically with biotic and abiotic factors. This study details the home range of the parthenogenic lizard, Aspidoscelis cozumela, an active forager microendemic to Cozumel Island, México, with high preference for open sand beaches. The home range of A. cozumela was compared with other species of Aspidoscelis (gonochoric and parthenogenetic) and other lizards that occupy coastal habitats. Furthermore, the biotic and abiotic factors that may influence home range were analyzed. This study was conducted in the beach located on the East side of the island (area of 4,000 M2) that is composed primarily of halophyte vegetation with high levels of sunlight. From 1999 to 2001, nine samples were taken which included the dry, rainy, "nortes", and breeding seasons. During each sampling, capture-mark-recapture techniques were conducted and the date, time of day, and snout-vent length (SVL) were recorded to the nearest millimeter. Individuals were located in the study area using a bi-coordinate reference using 10 x 10 m subdivisions of the habitat. Home range and home range overlap were calculated using the convex polygon method in McPaal and home range/SVL correlation was tested using Pearson's correlation. To calculate females home range, three or more recaptures were considered. A total of 20 home ranges that averaged 45.1 ± 14.0 m2 were obtained and no correlation between SVL and home range size was detected (p = 0.9229, n = 20). However, removing individuals with outlier home ranges (females with home ranges > 100 m2, n = 2) resulted in a positive correlation with SVL (r = 0.61, p = 0.0072, n = 18). A 22.9 ± 5.7% overlap in home range was also detected. The small home range of A. cozumela represents the smallest home range within the Aspidoscelis genus recorded to date (including both parthenogenetic and gonochoric species) and contrasts the theoretical predictions of broad home ranges for widely foraging species. Thermoregulatory benefits and a high population density may explain the small home range of A. cozumela. Although this species is highly adapted to the environmental conditions present on the open sand beaches, anthropogenic effects on these habitats by the development of tourism infrastructure may jeopardize their existence on Cozumel Island.

  14. First record of Porocephalus cf. clavatus (Pentastomida: Porocephalida) as a parasite on Bothrops asper (Squamata: Viperidae) in Costa Rica.

    PubMed

    Alvarado, G; Sánchez-Monge, A

    2015-11-01

    Pentastomids are parasites that infect respiratory cavities of vertebrates, they are pretty common but poorly known in wildlife veterinary. A Bothrops asper snake (Garman, 1884) was captured in the Caribbean region of Costa Rica and had its lung infested with pentastomids, identified as ca Porocephalus clavatus (Wyman, 1845). This represents the first record of Porocephalus (Humboldt, 1812) on B. asper as well as P. cf. clavatus in Costa Rica. Further studies are needed to clarify their taxonomic position, images and scanning electron microscopy photographs (SEM) of the specimens are given.

  15. A large and unusually colored new snake species of the genus Tantilla (Squamata; Colubridae) from the Peruvian Andes

    PubMed Central

    Venegas, Pablo J.

    2016-01-01

    A new colubrid species of the genus Tantilla from the dry forest of the northern Peruvian Andes is described on the basis of two specimens, which exhibit a conspicuous sexual dimorphism. Tantilla tjiasmantoi sp. nov. represents the third species of the genus in Peru. The new species is easily distinguished from its congeners by the combination of scalation characteristics and the unusual transversely-banded color pattern on the dorsum. A detailed description of the skull morphology of the new species is given based on micro-computed tomography images. The habitat of this new species is gravely threatened due to human interventions. Conservation efforts are urgently needed in the inter-Andean valley of the Maranon River. PMID:27994975

  16. Infestation of the southern alligator lizard (Squamata: Anguidae) by Ixodes pacificus (Acari: Ixodidae) and its susceptibility to Borrelia burgdorferi.

    PubMed

    Wright, S A; Lane, R S; Clover, J R

    1998-11-01

    To investigate the reservoir potential of the southern alligator lizard, Elgaria multicarinata (Blainville), for the Lyme disease spirochete, Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner, 14 lizards were collected from 1 county on each side of the northern Central Valley of California. Seven animals were collected from a Placer County site (Drivers Flat) and a Yolo County site (Cache Creek) where B. burgdorferi had been isolated previously from Ixodes pacificus Cooley & Kohls. Overall, the mean abundance of I. pacificus on all 14 lizards was 34.1 (range, 3-63) for larvae and 11.0 (range, 1-28) for nymphs. In captivity, field-attached I. pacificus larvae and nymphs required, on average, 12.6 (range, 1-37) and 14.4 (range, 5-44) d to feed to repletion, respectively. The prevalence of B. burgdorferi infection in host-seeking I. pacificus nymphs was 1.4% in Cache Creek Canyon and 9.9% in Drivers Flat. Attempts to isolate spirochetes from lizard blood or ticks that had fed on lizards and subsequently molted were unsuccessful as were efforts to cultivate spirochetes in lizard sera. These data suggest that the southern alligator lizard is not a competent reservoir for B. burgdorferi, although it is an important host for I. pacificus subadults.

  17. A fossil Diploglossus (Squamata, Anguidae) lizard from Basse-Terre and Grande-Terre Islands (Guadeloupe, French West Indies)

    NASA Astrophysics Data System (ADS)

    Bochaton, Corentin; Boistel, Renaud; Casagrande, Fabrice; Grouard, Sandrine; Bailon, Salvador

    2016-06-01

    Today, Diploglossine lizards (Anguidae) are common on the Greater Antillean Islands (West Indies), where they are represented by many endemic species. However these lizards are very rare on the Lesser Antillean Islands, where they are only represented by a single species, the Montserrat galliwasp (Diploglossus montisserrati). Here, we show that diploglossine lizards were present in the past on other Lesser Antillean islands, by reporting the discovery of Anguidae fossil remains in two Amerindian archaeological deposits and in a modern deposit. These remains are compared to skeletons of extant diploglossine lizards, including D. montisserrati, using X-ray microtomography of the type specimen of this critically endangered lizard. We also conducted a histological study of the osteoderms in order to estimate the putative age of the specimen. Our results show that the fossil specimens correspond to a member of the Diploglossus genus presenting strong similarities, but also minor morphological differences with D. montisserrati, although we postulate that these differences are not sufficient to warrant the description of a new species. These specimens, identified as Diploglossus sp., provide a new comparison point for the study of fossil diploglossine lizards and reflect the historical 17th century mentions of anguid lizards, which had not been observed since.

  18. A new species of Gekko (Squamata: Gekkonidae) from Tà Kóu Nature Reserve, Binh Thuan Province, Southern Vietnam

    PubMed Central

    Gamble, Tony

    2010-01-01

    A new species of Gekko Laurenti is described from Ta Kou Mountain, an isolated granitic peak in Ta Kou Nature Reserve, Ham Thuan Nam district, Binh Thuan province, southern Vietnam. The species is distinguished from its congeners by its moderate size, with snout to vent length (SVL) reaching a maximum 107.0 mm; dorsal pattern of 5–8 white vertebral blotches between the nape and sacrum and 6–8 pairs of short white bars on the flanks; 11–14 precloacal pores in males; 14–17 longitudinal rows of smooth dorsal tubercles; and 18–20 broad lamellae beneath the fourth toe. Gekko takouensis sp. nov. is the second endemic gekkonid discovered in the Ta Kou Nature Reserve, Cyrtodactylus takouensis Ngo & Bauer being the first. PMID:21547000

  19. Sex determination in Madagascar geckos of the genus Paroedura (Squamata: Gekkonidae): are differentiated sex chromosomes indeed so evolutionary stable?

    PubMed

    Koubová, Martina; Johnson Pokorná, Martina; Rovatsos, Michail; Farkačová, Klára; Altmanová, Marie; Kratochvíl, Lukáš

    2014-12-01

    Among amniote vertebrates, geckos represent a clade with exceptional variability in sex determination; however, only a minority of species of this highly diverse group has been studied in this respect. Here, we describe for the first time a female heterogamety in the genus Paroedura, the group radiated in Madagascar and adjacent islands. We identified homomorphic ZZ/ZW sex chromosomes with a highly heterochromatic W chromosome in Paroedura masobe, Paroedura oviceps, Paroedura karstophila, Paroedura stumpffi, and Paroedura lohatsara. Comparative genomic hybridization (CGH) revealed that female-specific sequences are greatly amplified in the W chromosome of P. lohatsara and that P. gracilis seems to possess a derived system of multiple sex chromosomes. Contrastingly, neither CGH nor heterochromatin visualization revealed differentiated sex chromosomes in the members of the Paroedura picta-Paroedura bastardi-Paroedura ibityensis clade, which is phylogenetically nested within lineages with a heterochromatic W chromosome. As a sex ratio consistent with genotypic sex determination has been reported in P. picta, it appears that the members of the P. picta-P. bastardi-P. ibityensis clade possess homomorphic, poorly differentiated sex chromosomes and may represent a rare example of evolutionary loss of highly differentiated sex chromosomes. Fluorescent in situ hybridization (FISH) with a telomeric probe revealed a telomere-typical pattern in all species and an accumulation of telomeric sequences in the centromeric region of autosomes in P. stumpffi and P. bastardi. Our study adds important information for the greater understanding of the variability and evolution of sex determination in geckos and demonstrates how the geckos of the genus Paroedura provide an interesting model for studying the evolution of the sex chromosomes.

  20. Acanthocephala in amphibians (Anura) and reptiles (Squamata) from Brazil and Paraguay with description of a new species.

    PubMed

    Smales, Lesley R

    2007-04-01

    In a survey of 1,732 amphibians and reptiles collected across São Paulo Province, Brazil, and 7 provinces in Paraguay, 26 species were found infected with acanthocephalans. Of 1,510 anurans, 14 anurans, representing 11 species, were infected with cystacanths of Centrorhynchus spp. and 1 anuran with cystacanths of Oligacanthorhynchus sp. Of 107 lizards, 1 lizard was infected with cystacanths of Centrorhynchus sp. and 1 lizard with cystacanths of Oligacanthorhynchus sp. Acanthocephalus caspanensis was found in 3 anurans (3 species) and Acanthocephalus lutzi in 3 anurans (2 species) and 2 snakes (2 species). The systematic position of A. lutzi cannot be resolved using presently available morphological data. Acanthocephalus saopaulensis n. sp. was found in a single individual of Bufo ictericus. The new species can be differentiated from all its congeners except A. caspanensis in having a sigmoid-shaped male posterior end and from A. caspanensis in having a proboscis armature of 16 rows of 5-7 hooks rather than 18-19 rows of 6-7 hooks and larger eggs. The status of Acanthocephalus and Pseudoacanthocephalus continues to be problematic.

  1. A new species of pine anole from the Sierra Madre del Sur in Oaxaca, Mexico (Reptilia, Squamata, Dactyloidae: Anolis).

    PubMed

    Köhler, Gunther; Pérez, Raúl Gómez Trejo; Petersen, Claus Bo P; de La Cruz, Fausto R Mendez

    2014-01-09

    We describe the new species Anolis peucephilus sp. nov. from the Pacific versant of southern Mexico. Anolis peucephilus differs from all congeners by having a combination of (1) smooth ventral scales; (2) usually a patch of three greatly enlarged supraocular scales; (3) extremely short hind legs, longest toe of adpressed hind leg reaching to a point between levels of axilla and ear opening, ratio shank length/snout-vent length 0.18-0.21; (4) circumnasal usually in contact with first supralabial; and (5) a large yellowish orange dewlap in males and a very small to small white dewlap in females. In external morphology, A. peucephilus is most similar to A. omiltemanus from which it differs by having even shorter hind legs with the longest toe of adpressed hind leg reaching to a point between levels of axilla and ear opening (versus usually to ear opening, occasionally to slightly beyond ear opening or to a point between shoulder and ear opening in A. omiltemanus), a slightly larger dewlap in females, to 64 mm2 (versus to 41 mm2 in A. omiltemanus), the circumnasal usually in contact with the first supralabial (versus those scales separated by the presence of a subnasal in A. omiltemanus), and 4-6 internasal scales in the new species (versus usually 6-7 in A. omiltemanus). Furthermore, A. peucephilus differs from A. omiltemanus in hemipenial morphology (no finger-like processus on asulcate side in A. peucephilus versus such a processus present in A. omiltemanus). Also, in a preliminary molecular genetic analysis of the mitochondrial CO1 gene fragment, A. peucephilus has a genetic distance of 11.5% from A. omiltemanus. Anolis peucephilus was collected at night while the lizards were sleeping in pine trees, 2-10 m above the ground.

  2. A new species of Alopoglossus lizard (Squamata, Gymnophthalmidae) from the tropical Andes, with a molecular phylogeny of the genus.

    PubMed

    Torres-Carvajal, Omar; Lobos, Simón E

    2014-01-01

    We describe a new species of Alopoglossus from the Pacific slopes of the Andes in northern Ecuador based on morphological and molecular evidence. The new species differs most significantly from all other congeners in having a double longitudinal row of widened gular scales, lanceolate dorsal scales in transverse rows, 29-32 dorsal scales in a transverse row at midbody, and 4 longitudinal rows of ventrals at midbody. It is most similar in morphology to A. festae, the only species of Alopoglossus currently recognized in western Ecuador. We analyze the phylogenetic relationships among species of Alopoglossus based on the mitochondrial gene ND4. Cis-Andean [east of the Andes] and Trans-Andean [west of the Andes] species are nested in two separate clades, suggesting that the uplift of these mountains had an important effect in the diversification of Alopoglossus. In addition, we present an updated key to the species of Alopoglossus.

  3. Additions to Philippine Slender Skinks of the Brachymeles bonitae Complex (Reptilia: Squamata: Scincidae) III: a new species from Tablas Island.

    PubMed

    Davis, Drew R; Geheber, Aaron D; Watters, Jessa L; Penrod, Michelle L; Feller, Kathryn D; Ashford, Alissa; Kouri, Josh; Nguyen, Daniel; Shauberger, Kathryn; Sheatsley, Kyra; Winfrey, Claire; Wong, Rachel; Sanguila, Marites B; Brown, Rafe M; Siler, Cameron D

    2016-06-28

    Studies of the diversity of Philippine amphibians and reptiles have resulted in the continued description of cryptic species. Species formerly thought to range across multiple recognized faunal regions are now considered to be assemblages of multiple unique species, each restricted to a single faunal region. This pattern continues to hold true when considering Philippine skinks of the genus Brachymeles. Recent studies have resulted in the description of numerous unique species with many exhibiting various degrees of digit loss or limb reduction, as well as suggesting that unique lineages are still present in the B. bonitae Complex. In this paper, we describe a new species of fossorial skink within this species complex from Tablas Island based on collections made nearly 50 years ago. Although no genetic data are available for the new species, examinations of morphological data (qualitative traits, meristic counts, and mensural measurements) support its distinction from all other members of the genus. Brachymeles dalawangdaliri sp. nov. is differentiated from other members of the genus based on a suite of unique phenotypic characteristics, including a small body size (SVL 66.0-80.9 mm), bidactyl fore-limbs, digitless, unidactyl, or bidactyl hind limbs, a high number of presacral vertebrae (49), the absence of auricular openings, and distinct dorsal head scale patterns. The description of the new species increases the diversity of endemic vertebrates recognized to occur in the Romblon Island Group in the central Philippines.

  4. [A family of short retroposons (Squaml) from squamate reptiles (Reptilia: Squamata): structure, evolution and correlation with phylogeny].

    PubMed

    Kosushkin, S A; Borodulina, O R; Solov'eva, E N; Grechko, V V

    2008-01-01

    We have isolated and characterised sequences of a SINE family specific for squamate reptiles from a genome of lacertid lizard that we called Squam1. Copies are 360-390 bp in length and share a significant similarity with tRNA gene sequence on its 5'-end. This family was also detected by us in DNA of representatives of varanids, iguanids (anolis), gekkonids, and snakes. No signs of it were found in DNA of mammals, birds, amphibians, and crocodiles. Detailed analysis of primary structure of the retroposons obtained by us from genomic libraries or GenBank sequences was carried out. Most taxa possess 2-3 subfamilies of the SINE in their genomes with specific diagnostic features in their primary structure. Individual variability of copies in different families is about 85% and is just slightly lower on the genera level. Comparison of consensus sequences on family level reveals a high degree of structural similarity with a number of specific apomorphic features which makes it a useful marker of phylogeny for this group of reptiles. Snakes do not show specific affinity to varanids when compared to other lizards, as it was suggested earlier.

  5. Out of the deep: cryptic speciation in a Neotropical gecko (Squamata, Phyllodactylidae) revealed by species delimitation methods.

    PubMed

    Domingos, Fabricius M C B; Bosque, Renan J; Cassimiro, José; Colli, Guarino R; Rodrigues, Miguel T; Santos, Marcella G; Beheregaray, Luciano B

    2014-11-01

    Levels of biodiversity in the Neotropics are largely underestimated despite centuries of research interest in this region. This is particularly true for the Cerrado, the largest Neotropical savanna and a formally recognized biodiversity hotspot. Molecular species delimitation methods have become essential tools to uncover cryptic species and can be notably robust when coupled with morphological information. We present the first evaluation of the monophyly and cryptic speciation of a widespread Cerrado endemic lizard, Gymnodactylus amarali, using phylogenetic and species-trees methods, as well as a coalescent-based Bayesian species delimitation method. We tested whether lineages resulting from the analyses of molecular data are morphologically diagnosed by traditional meristic scale characters. We recovered eight deeply divergent molecular clades within G. amarali, and two additional ones from seasonally dry tropical forest enclaves between the Cerrado and the Caatinga biomes. Analysis of morphological data statistically corroborated the molecular delimitation for all groups, in a pioneering example of the use of support vector machines to investigate morphological differences in animals. The eight G. amarali clades appear monophyletic and endemic to the Cerrado. They display several different properties used by biologists to delineate species and are therefore considered here as candidates for formal taxonomic description. We also present a preliminary account of the biogeographic history of these lineages in the Cerrado, evidence for speciation of sister lineages in the Cerrado-Caatinga contact, and highlight the need for further morphological and genetic studies to assess cryptic diversity in this biodiversity hotspot.

  6. Character congruence and phylogenetic signal in molecular and morphological data sets: a case study in the living Iguanas (Squamata, Iguanidae).

    PubMed

    Sites, J W; Davis, S K; Guerra, T; Iverson, J B; Snell, H L

    1996-10-01

    The lizard family Iguanidae comprises eight living genera distributed throughout the New and Old World, and includes several island endemics. We reconstruct phylogenetic relationships among these genera using 90 previously published morphological characters, to which we add a molecular (mtDNA sequence) data set that includes 742 nucleotides of the ND4 gene and the complete sequences of the histidine, serine, and leucine tRNAs (217 nucleotides). Trees were initially constructed separately from these three data sets, and then tested for significant conflict in topologies that would suggest the influence of different evolutionary processes. The three data sets were then combined, and a single tree was obtained from the total evidence that permitted identification of potential sources of character incongruence. Several additional analyses of the combined data sets were repeated with sequential deletion of successive classes of homoplastic characters, and we show that the same single tree topology is recovered in most cases. However, part of the tree structure collapses when the matrix of combined characters is completely purged of all homoplastic characters. We argue that this extreme results in an unacceptable loss of phylogenetic information, and we present a single phylogenetic hypothesis for all living genera of iguanas. We show that this hypothesis is significantly more parsimonious than either of two previously published trees, and we discuss the evolution and biogeography of the Iguanidae based on the preferred hypothesis.

  7. A new phasmid gecko (Squamata: Diplodactylidae: Strophurus) from the Arnhem Plateau: more new diversity in rare vertebrates from northern Australia.

    PubMed

    Oliver, Paul M; Parkin, Tom

    2014-10-22

    The Arnhem Plateau is a rugged expanse of sandstone escarpment in the Australian Monsoonal Tropics with a highly endemic biota. Here we describe a new species of small spinifex dwelling Strophurus (phasmid gecko) that also appears to be endemic to this region. Strophurus horneri sp. nov. can be diagnosed from all congeners by aspects of size, coloration and scalation. Even with the description of this new species, however, levels of morphological and genetic diversity within Strophurus from the stone country of the Northern Territory suggest additional divergent lineages are present. A number of recent studies have now provided preliminary evidence of evolutionary diversity within the Arnhem Plateau, but data remains scant and almost nothing is known about how topography and historical processes have shaped the endemic biota of this region. 

  8. A new leaf-tailed gecko of the Uroplatus ebenaui group (Squamata: Gekkonidae) from Madagascar's central eastern rainforests.

    PubMed

    Ratsoavina, Fanomezana Mihaja; Ranjanaharisoa, Fiadanantsoa Andrianja; Glaw, Frank; Raselimanana, Achille P; Miralles, Aurélien; Vences, Miguel

    2015-08-21

    We describe a new leaf-tailed gecko species of the Uroplatus ebenaui group from the eastern central rainforests of Madagascar, which had previously been considered as a confirmed candidate species. Our description of Uroplatus fiera sp. nov. relies on integrating evidence from molecular and morphological characters and is based on newly collected material from two localities. A phylogenetic analysis based on multiple mitochondrial DNA fragments places the new species as sister to a lineage of uncertain status (Uroplatus ebenaui [Ca8]), and the clade consisting of these two lineages is sister to a further undescribed candidate species (U. ebenaui [Ca1]). This entire clade is sister to U. phantasticus plus another candidate species. The new species differs from these close relatives, and all other congenerics, by strong differences in DNA sequences of mitochondrial genes (>8.5% uncorrected p-distance in 16S rDNA to all nominal species of the genus) and lacks shared alleles with any of the nominal species in the nuclear CMOS gene. From its closest relatives the new species further differs in its much smaller tail size (relative to U. phantasticus), and a narrower tail, fewer supralabials, and more toe lamellae (relative to U. ebenaui [Ca1]). Morphologically the new species is most similar to U. ebenaui but differs in its larger body size and unpigmented oral mucosa. Given its distribution in central eastern Madagascar, with records from near Fierenana and Ambatovy, its range overlaps with that of U. phantasticus. Based on examination of the U. phantasticus holotype, we confirm that this latter has a blackish pigmented oral mucosa as do those specimens typically attributed to this nomen, thereby confirming its distinctness from U. fiera sp. nov., in which the mucosa is unpigmented.

  9. A new species of karst-dwelling bent-toed gecko (Squamata: Gekkonidae) from Khammouane Province, central Laos.

    PubMed

    Luu, Vinh Quang; Nguyen, Truong Quang; Le, Minh Duc; Bonkowski, Michael; Ziegler, Thomas

    2016-02-10

    We describe a new species of the genus Cyrtodactylus from Khammouane Province, central Laos based on morphological features and molecular data. Morphologically, Cyrtodactylus bansocensis sp. nov. is differentiated from other congeners by a unique combination of the following characters: medium size, SVL reaching 74.0 mm; dorsal pattern consisting of four light transverse bands between limb insertions; supranasals in contact with each other; dorsal tubercles at midbody in 14-15 irregular rows; lateral folds present without interspersed tubercles; ventral scales between ventrolateral folds 34-35; precloacal and femoral pores in males 34, separated by four poreless scales in the male holotype and in a continuous row in the male paratype; enlarged femoral and precloacal scales present; postcloacal tubercles 5-7 on each side; dorsal tubercles present at tail base; and subcaudal scales transversely enlarged. Molecular analyses revealed the new species to be closely related to Cyrtodactylus rufford, which is also found in Khammouane Province.

  10. A new species of arboreal forest-dwelling gecko (Hemidactylus: Squamata: Gekkonidae) from coastal Kenya, East Africa.

    PubMed

    Malonza, Patrick K; Bauer, Aaron M

    2014-04-09

    A new species of Hemidactylus, H. mrimaensis sp. nov., is described from coastal kaya forests of Kenya. This small-sized, arboreal gecko may be distinguished from its probable close relative, the sympatric H. mabouia, by its more slender habitus, golden color, small adult body length (maximum SVL 50 mm in females) and features of scalation including keeled dorsal tubercles in 11-14 longitudinal rows, pointed tubercles on tail larger than those on the dorsum, and 32-34 precloacal pores in males. This gecko may be endemic to the coastal forests and given the ongoing threats to this habitat, the species is of high conservation concern.

  11. Cyrtodactylus rufford, a new cave-dwelling bent-toed gecko (Squamata: Gekkonidae) from Khammouane Province, central Laos.

    PubMed

    Luu, Vinh Quang; Calame, Thomas; Nguyen, Truong Quang; Le, Minh Duc; Bonkowski, Michael; Ziegler, Thomas

    2016-01-21

    We describe a new species of the gekkonid genus Cyrtodactylus from Khammouane Province, central Laos based on morphological and molecular data. Morphologically, Cyrtodactylus rufford sp. nov. differs from its congeners by a unique combination of the following characters: medium size, SVL reaching 72.5 mm; dorsal pattern with three or four light transverse bands between limb insertions; one intersupranasal; 14-16 irregular dorsal tubercle rows at midbody, weakly developed in the paravertebral region; 27-29 ventral scale rows between ventrolateral folds; 42-43 precloacal and femoral pores in a continuous row in males, enlarged femoral and precloacal scales present; 4 or 5 postcloacal tubercles on each side; dorsal tubercles present at base of tail; medial subcaudal scales enlarged. Molecular analyses show that the new species is closely related to C. khammouanensis, which was originally described from Khammouane Province.

  12. Redescription of the rare Philippine false gecko Pseudogekko brevipes (Reptilia: Squamata: Gekkonidae) and description of a new species.

    PubMed

    Davis, Drew R; Watters, Jessa L; Köhler, Gunther; Whitsett, Collin; Huron, Nicholas A; Brown, Rafe M; Diesmos, Arvin C; Siler, Cameron D

    2015-09-22

    Recent investigations into the species diversity of false geckos (genus Pseudogekko Taylor) have revealed several cryptic species, highlighting the need for a more thorough understanding of diversity within this enigmatic genus of endemic Philippine geckos. Newly available genetic data reveal that two of the four currently recognized species are complexes of multiple deeply divergent evolutionary lineages. In this paper we evaluate species diversity in one of these complexes, P. brevipes Boettger, and describe one additional new species. For nearly a century, P. brevipes has been recognized as a single, "widespread" species with a geographic range spanning two major faunal regions and several island groups. Poor understanding of this species has persisted due to both limited sampling and its apparent rarity. We evaluate both morphological and genetic data to define species limits in P. brevipes, and find character-based evidence to justify the recognition of two unique evolutionary lineages, one of which we describe as a new species (P. atiorum sp. nov.). The species included in this study have allopatric distributions and differ from congeners by numerous diagnostic characters of external morphology, and therefore should be recognized as full species in accordance with lineage-based species concepts. This newly described species increases the total number of species of Pseudogekko to seven.

  13. Edema induced by Bothrops asper (Squamata: Viperidae) snake venom and its inhibition by Costa Rican plant extracts.

    PubMed

    Badilla, Beatriz; Chaves, Fernando; Mora, Gerardo; Poveda, Luis J

    2006-06-01

    We tested the capacity of leaf (Urera baccifera, Loasa speciosa, Urtica leptuphylla, Chaptalia nutans, and Satureja viminea) and root (Uncaria tomentosa) extracts to inhibit edema induced by Bothrops asper snake venom. Edema-forming activity was studied plethysmographically in the rat hind paw model. Groups of rats were injected intraperitoneally with various doses of each extract and, one hour later, venom was injected subcutaneously in the right hind paw. Edema was assessed at various time intervals. The edematogenic activity was inhibited in those animals that received an injection U. tomentosa, C. nutans or L. speciosa extract. The extract of U. baccifera showed a slight inhibition of the venom effect. Extract from S. viminea and, to a lesser extent that of U. leptuphylla, induced a pro-inflammatory effect, increasing the edema at doses of 250 mg/kg at one and two hours.

  14. Catalogue of distribution of lizards (Reptilia: Squamata) from the Brazilian Amazonia. I. Dactyloidae, Hoplocercidae, Iguanidae, Leiosauridae, Polychrotidae, Tropiduridae.

    PubMed

    Ribeiro-Júnior, Marco A

    2015-07-08

    I present distribution data of all Dactyloidae, Hoplocercidae, Iguanidae, Leiosauridae, Polychrotidae and Tropiduridae lizards known from the Brazilian Amazonia, totaling 40 species-level taxa, belonging to 11 genera. This represents four more species-level taxa than previously reported for these families. Data were based on the direct examination of 41,243 specimens deposited in three North American and eight Brazilian musea, including the main collections harboring Amazonian material. Most species (62.5%) are endemic to the Amazonia; non-endemic species are mainly associated with open dry (semideciduous) forest or open vegetation (savanna) enclaves in Amazonia, with a few exceptions. As a whole, seven taxa are widespread in Amazonia, one is restricted to eastern Amazonia, three to western Amazonia, five to northern Amazonia (either in part of it or widespread in the Guiana region), two to northwestern Amazonia, one to southern Amazonia, nine to southwestern Amazonia, and seven to the southern peripheral portion of Amazonia. Five species have unique distributions and five species have a distribution that is congruent with one of the areas of endemism (AE) recognized for other organisms (birds and primates). The first herpetological gazetteer for the Brazilian Amazonia with about 3,600 georeferenced localities was also produced.

  15. The intestinal helminth community of the spiny-tailed lizard Darevskia rudis (Squamata, Lacertidae) from northern Turkey.

    PubMed

    Roca, V; Jorge, F; Ilgaz, Ç; Kumlutaş, Y; Durmuş, S H; Carretero, M A

    2016-03-01

    Populations of the lizard Darevskia rudis (Bedriaga, 1886) from northern Anatolia were examined for intestinal parasites in adult specimens. One cestode, Nematotaenia tarentolae López-Neyra, 1944 and four nematode species, Spauligodon saxicolae Sharpilo, 1962, Skrjabinelazia hoffmanni Li, 1934, Oswaldocruzia filiformis (Goeze, 1782) and Strongyloides darevskyi Sharpilo, 1976, were found. Three of these nematodes, S. saxicolae, S. hoffmanni and S. darevskyi are suggested to be part of a module in the network of Darevskia spp. and their parasites. Only one, S. darevskyi, was identified as a Darevskia spp. specialist. The very low infection and diversity parameters are indicative of the depauperate helminth communities found in this lacertid lizard, falling among the lowest within the Palaearctic saurians. Nevertheless these values are higher than those found in parthenogenetic Darevskia spp. Interpopulation variation in the intensity of S. saxicolae and N. tarentolae is attributable to local changes in ecological conditions. On the other hand, parasite abundance and richness increased in the warmer localities, while the effect of lizard sex and size on infection was negligible. The structure of these helminth communities in D. rudis are compared with those observed in other European lacertid lizards.

  16. Hemipenes in females of the Mexican viviparous lizard Barisia imbricata (Squamata: Anguidae): an example of heterochrony in sexual development.

    PubMed

    Martínez-Torres, Martín; Rubio-Morales, Beatriz; Piña-Amado, José Juan; Luis, Juana

    2015-01-01

    The sexual development of saurians follows a similar pattern to that described for other amniotes. Changes in the timing or sequence of development events are known as heterochrony. We describe the pattern of sexual development in the viviparous Mexican lizard Barisia imbricata and report heterochrony in the regression of hemipenes in this lizard. We collected gestating females; some lizards were subjected to partial hysterectomy and the embryos were processed using routine histological technique to assess gonadal development; the remaining embryos were used to assess the development of hemipenes. Other pregnant females were kept in captivity in individual terraria until the time of delivery. All neonates were sexed by eversion of hemipenes and some of their body characteristics were recorded. Several neonates were sacrificed and processed to establish gonadal histology and the young of the remaining litters were maintained in captivity to observe the fate of the hemipenes in both sexes. Gonadal development began at embryonic stage 33 and the hemipenes were visible at the same stage. In the neonates, the ovary contained oogonias and ovarian follicles, whereas the testicles showed testicular cords. All neonates had hemipenes and sex could only be established through direct observation of the reproductive ducts and gonadal histology. The hemipenes regression in the females begins after approximately 7 months of postnatal development and concludes at about 15 months of age. We think that the delayed regression of the hemipenes reflects evolutionary differences among reptiles and may be an indication of a stage in the evolutionary process of this species.

  17. Oogenesis and ovarian histology in two populations of the viviparous lizard Sceloporus grammicus (Squamata: Phrynosomatidae) from the central Mexican Plateau.

    PubMed

    Lozano, Abraham; Ramírez-Bautista, Aurelio; Uribe, Mari Carmen

    2014-08-01

    The annual histological changes in ovarian morphology (oogenesis, follicular atresia, and corpus luteum) are described for the Mexican lizard Sceloporus grammicus, in two populations that inhabit contrasting environments (vegetation categories, climate, precipitation, and temperature) from Hidalgo State, Mexico. Two germinal beds were situated on the dorsal surface of each ovary of this species. In both the populations, oogenesis involves two major processes: previtellogenesis and vitellogenesis. The histological changes during previtellogenesis are similar to those for other reptilian sauropsids, whereas vitellogenesis differs and the features of this last process are described for the first time. In early previtellogenesis, primary oocytes have fibrillar chromosomes and the ooplasm stains slightly. The primordial follicles are surrounded by a granulosa composed of cuboidal follicular cells. During late previtellogenesis, the oocyte had an eccentric nucleus with lamp-brush chromosomes and multiple nucleoli. The granulosa becomes multilayered and polymorphic, containing three cell types: small, intermediate, and pyriform. The zona pellucida was homogeneous and clearly observed. In early vitellogenesis, the oocyte showed several small acidophilic granules distributed in the center and the periphery of the oocyte. As vitellogenesis progresses, the yolk platelets move toward the central area of the oocyte and they fuse to form acidophilic and homogeneous yolk. Lipid droplets were distributed irregularly in the ooplasm of the oocyte. In Zacualtipán, the results revealed a strong seasonal reproductive activity. Females had vitellogenic follicles from July to September, and pregnant females were founded from September to March. In Tizayuca, the results showed an unusual pattern of reproductive activity. Females with vitellogenic follicles and pregnant females were found throughout the year, indicating continuous reproduction. We suggest that the observed differences in reproductive activity from these populations indicate adaptative fine tuning in response to local environmental conditions. These results contribute to the knowledge of variation in vitellogenesis and reproductive strategies of this species and among spiny lizards overall.

  18. [Displacements of the green iguana (Iguana iguana) (Squamata: Iguanidae) during the dry season in La Palma, Veracruz, Mexico].

    PubMed

    Morales-Mávil, Jorge E; Vogt, Richard C; Gadsden-Esparza, Héctor

    2007-06-01

    The green iguana (Iguana iguana) is said to be primarily sedentary, although the females travel long distances to nest. Displacement patterns must be known to help predict the effects of environmental disturbance on iguanas' survival. We studied nesting season (February-July) movements in La Palma, Los Tuxtlas, Veracruz, Mexico (18 degrees 33' N, 95 degrees 03' W). Individual movements and activity were monitored by radio tracking. The transmitters were implanted surgically in eight adult iguanas (four males and four females). Snout vent length (SVL) was used to determine the relationship between size of the body and size of home range. To estimate the size of home range, three or more points were used. Minimum convex polygons estimates of home range were calculated with McPAAL. The iguanas were radio-located between 23 and 30 occasions, mainly in trees (56% between 3-9 m); only 4% were localized under a height of 3 m (forest floor). The occupation area mean was larger for males (9,158.06+/-3,025.3 m2 vs. 6,591.24+/-4,001.1 m2) although the differences were not significant (t= 0.51, p>0.05). SVL was correlated with home range (r= 0.76; gl= 7; p<0.05). Breeding males defended their home range vigorously against other adult males. We observed one separate male home range and large portions of overlap between the sexes. The home range generally formed a conglomerate of polygons and only two had linear shapes along the river: apparently iguanas use the riparian vegetation for foraging. The females display two strategies for nesting: 1) moving to the sandy area near the sea or, 2) laying eggs near the river, in loam. Iguanas responded to habitat fragmentation and reduction by modifying their nesting strategy.

  19. Biogeography of the Lizard Genus Tropidurus Wied-Neuwied, 1825 (Squamata: Tropiduridae): Distribution, Endemism, and Area Relationships in South America

    PubMed Central

    de Carvalho, André Luiz Gomes; de Britto, Marcelo Ribeiro; Fernandes, Daniel Silva

    2013-01-01

    Based on comprehensive distributional records of the 23 species currently assigned to the lizard genus Tropidurus, we investigated patterns of endemism and area relationships in South America. Two biogeographic methods were applied, Parsimony Analysis of Endemicity (PAE) and Brooks Parsimony Analysis (BPA). Two areas of endemism were detected by PAE: the first within the domains of the semiarid Brazilian Caatinga, which includes seven endemic species, and the second in the region of the Serranía de Huanchaca, eastern Bolivia, in which three endemic species are present. The area cladograms recovered a close relationship between the Atlantic Forest and areas of the South American open corridor. The results revealed a close relationship among the provinces Caatinga (Cerrado, Parana Forest (Pantanal+Chaco)). The uplift of the Brazilian Central Plateau in the Late Pliocene-Early Pleistocene (4-2 Myr BP) has been interpreted as a major event responsible for isolation and differentiation of biotas along these areas. However, we emphasize that without the establishment of a temporal framework concerning the diversification history of Tropidurus it is premature to correlate cladogenetic events with specific time periods or putative vicariant scenarios. The limiting factors hampering the understanding of the biogeographic history of this genus include (1) the absence of temporal references in relation to the diversification of distinct clades within Tropidurus; (2) the lack of an appropriate taxonomic resolution of the species complexes currently represented by widely distributed forms; and (3) the need for a comprehensive phylogenetic hypothesis. We suggest that these three important aspects should be prioritized in future investigations. PMID:23527261

  20. Dragons in the mist: three new species of Pseudocalotes Fitzinger (Squamata: Agamidae) from the sky island archipelago of Peninsular Malaysia.

    PubMed

    Grismer, L Lee; Quah, Evan S H; Wood, Perry L Jr; Anuar, Shahrul; Muin, Abdul; Davis, Hayden R; Murdoch, Matthew L; Grismer, Jesse L; Cota, Michael; Cobos, Anthony J

    2016-07-07

    An integrative taxonomic analysis is used to delimit and describe three new species of Pseudocalotoes from the sky island archipelago of the Banjaran (=mountain range) Titiwangsa of Peninsular Malaysia. Pseudocalotes drogon sp. nov., from Fraser's Hill, Pahang is basal to the sister species P. larutensis from Bukit Larut, Perak in the Banjaran Bintang and the new species P. rhaegal sp. nov. from Cameron Highlands, Pahang. Pseudocalotes drogon sp. nov. is differentiated from all other species of Psuedocalotes by having the combination of a flat rostrum; seven postrostrals; an interparietal; 11 circumorbitals; five canthals; 7-10 superciliaries; one scale between the rostral and nasal; nine supralabials; eight infralabials; 10 postnasal-suborbital scales; four postmentals; five or six sublabials; five or six chinshields; 47 smooth, wide, gular scales; weak transverse gular and antehumeral folds; two enlarged scales between the ear and eye; enlarged upper and lower posttemporals; a single enlarged supratympanic; no enlarged postrictals; three large scales bordering the dorsal margin of the ear opening; large pretympanic scales; eight scales in the nuchal crest not separated by a gap; enlarged vertebral scales extending to the tip of the tail; keeled and non-plate-like scales on flanks; 51 midbody scales; midventrals smaller than dorsals; 19 subdigital lamellae on the fourth finger; 23 subdigital lamellae on the fourth toe; preaxial scales on third toe enlarged and spinose; subdigital lamellae not unicarinate; HW/HL 0.52; HL/SVL 0.31; no elbow or knee patches; and a male dewlap color of lime-green bearing a central yellow spot. Pseudocalotes rhaegal sp. nov. is differentiated from all other Psuedocalotes by having the combination of a convex rostrum; 6-8 postrostrals; an interparietal; nine or 10 circumorbitals; five canthals; 7-10 superciliaries; one or two scales between the rostral and nasal scales; eight or nine supralabials; seven or eight infralabials; 11 or 12 postnasal-suborbital scales; four postmentals; four or five chinshields; 40-45 smooth, wide, gular scales; no transverse gular fold; a weak antehumeral fold; three or four enlarged scales between the ear and eye; an enlarged upper and lower posttemporal; an enlarged supratympanic; no enlarged postrictals; no large scales bordering the upper margin of the ear opening or in the pretympanic region; 6-8 enlarged nuchal crest scales not separated by a gap; enlarged vertebral scales extending to the base of the tail; weakly keeled, non-plate-like scales on the flanks; 52-58 midbody scales; midventrals smaller than dorsals; 19-21 subdigital lamellae on the fourth finger; 22-26 subdigital lamellae on the fourth toe; preaxial scales on the third enlarged and rounded; subdigital lamellae not unicarinate; HW/HL 0.50-0.54; HL/SVL 0.28-0.30; no elbow or knee patches; and female dewlap color yellow bearing a purple base. The analyses also indicated that the new species, P. viserion sp. nov. from Genting Highlands, Pahang in the southern section of the Banjaran Titiwangsa is the sister species of P. flavigula from Cameron Highlands 121 km to the north and can be separated from all other species of Psuedocalotes by having the combination of three postrostrals; 10 circumorbitals; four or five canthals; 5-7 superciliaries; rostral and nasals in contact; supralabials contacting the nasal; six or seven supralabials; six or seven infralabials; two or three postmentals; 47 or 48 smooth, flat, gular scales; three chinshields; weak transverse gular and antehumeral folds; two enlarged scales between the ear and eye; an enlarged upper and lower posttemporal; an enlarged supratympanic; no enlarged postrictals; 7-9 nuchal crest scales lacking gaps and not extending beyond midbody; weakly keeled and plate-like scales on the flanks; 35-38 midbody scales; ventrals smaller than dorsals; 22 or 23 subdigital lamellae on the fourth finger; 26 or 27 subdigital lamellae on the fourth toe; preaxial scales on the third toe not modified; subdigital scales not unicarinate; HW/HL 0.62; no white marking below the eye; dewlap in males yellow; and no elbow or knee patches. Pseudocalotes rhaegal sp. nov. most likely occurs in syntopy with P. flavigula in Tanah Rata at Cameron Highlands and its discovery adds to a growing body of literature detailing the recent descriptions of several new, upland, closely related, sympatric species in Peninsular Malaysia. Another new population referred to here as Pseudocalotes sp. nov. from the Hala-Bala Wildlife Sanctuary, Betong District, Yala Province, Thailand is discussed. The discovery and description of these three new Pseudocalotes from the upland regions of Peninsular Malaysia continues to underscore the remarkably high herpetological diversity and ecological complexity in this sky island archipelago that is still underestimated, unappreciated, and unprotected.

  1. Surface structure and frictional properties of the skin of the Amazon tree boa Corallus hortulanus (Squamata, Boidae).

    PubMed

    Berthé, R A; Westhoff, G; Bleckmann, H; Gorb, S N

    2009-03-01

    The legless locomotion of snakes requires specific adaptations of their ventral scales to maintain friction force in different directions. The skin microornamentation of the snake Corallus hortulanus was studied by means of scanning electron microscopy and the friction properties of the skin were tested on substrates of different roughness. Skin samples from various parts of the body (dorsal, lateral, ventral) were compared. Dorsal and lateral scales showed similar, net-like microornamentation and similar friction coefficients. Average friction coefficients for dorsal and lateral scales on the epoxy resin surfaces were 0.331 and 0.323, respectively. In contrast, ventral scales possess ridges running parallel to the longitudinal body axis. They demonstrated a significantly lower friction coefficient compared to both dorsal and lateral scales (0.191 on average). In addition, ventral scales showed frictional anisotropy comparing longitudinal and perpendicular direction of the ridges. This study clearly demonstrates that different skin microstructure is responsible for different frictional properties in different body regions.

  2. Antifungal and Insecticidal Activity from Two Juniperus Essential Oils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Essential oils of two Tibetan Junipers Juniperus saltuaria and J. squamata var. fargesii (Cupressaceae) were obtained by distilling dried leaves and branches using a Clevenger apparatus. Sixty-seven compounds from J. saltuaria and 58 compounds from J. squamata var. fargesii were identified by gas c...

  3. Description of the hemipenial morphology of Tupinambis quadrilineatus Manzani and Abe, 1997 (Squamata, Teiidae) and new records from Piauí, Brazil

    PubMed Central

    da Silva, Marcélia Basto; de Lima-Filho, Geraldo Rodrigues; Cronemberger, Áurea Aguiar; Carvalho, Leonardo Sousa; Manzani, Paulo Roberto; Vieira, Jânia Brito

    2013-01-01

    Abstract Few data are available on the morphology of the hemipenis of teiid lizards, especially those of the recently-defined genus Tupinambis, a widely-distributed group of large-bodied lizards. This study provides an illustrated description of the hemipenis of Tupinambis quadrilineatus, which is similar to that of other representatives of the Tupinambinae subfamily. New records of the species from the state of Piauí, in northeastern Brazil, are also presented. PMID:24363597

  4. A relict lineage and new species of green palm-pitviper (Squamata, Viperidae, Bothriechis) from the Chortís Highlands of Mesoamerica

    PubMed Central

    Townsend, Josiah H.; Medina-Flores, Melissa; Wilson, Larry David; Jadin, Robert C.; Austin, James D.

    2013-01-01

    Abstract A new species of palm-pitviper of the genus Bothriechis is described from Refugio de Vida Silvestre Texíguat in northern Honduras. The new species differs from congeners by having 19 dorsal scale rows at midbody, a bright green dorsal coloration in adults, the prelacunal scale fused to the second supralabial, and in representing a northern lineage that is sister to Bothriechis lateralis, which is distributed in Costa Rica and western Panama and is isolated from the new taxon by the Nicaraguan Depression. This represents the 15th endemic species occurring in Refugio de Vida Silvestre Texíguat, one of the richest herpetofaunal sites in Honduras, itself being the country with the highest degree of herpetofaunal endemism in Central America. We name this new species in honor of a Honduran conservationist slain in fighting against illegal logging, highlighting the sacrifices of rural activists in battling these issues and the critical importance of conservation in these areas. PMID:23794885

  5. A reassessment of Melanophidium Günther, 1864 (Squamata: Serpentes:
    Uropeltidae) from the Western Ghats of peninsular India, with the description of a new species.

    PubMed

    Gower, David J; Giri, Varad; Captain, Ashok; Wilkinson, Mark

    2016-03-04

    A new species of the uropeltid snake genus, Melanophidium Günther, 1864 is described based on a series of eight specimens. Melanophidium khairei sp. nov. is the fourth species described in the genus, and the first for 144 years. Superficially M. khairei sp. nov. resembles M. punctatum Beddome, 1871 in being piebald and punctate (and it was previously misidentified as M. punctatum), but in many scalation characters it more closely resembles M. wynaudense (Beddome, 1863). The new species occurs in southern Maharashtra, Goa, and northern Karnataka, in the Western Ghats region of peninsula India. It is the most northerly member of its genus. Lectotypes and paralectotypes are designated for M. wynaudense, M. bilineatum Beddome, 1870, and M. punctatum. A new key to the species of Melanophidium is presented. Aspects of the morphology, taxonomy and distribution of the three previously described species of Melanophidium are reviewed and revised.

  6. Cryptic, Sympatric Diversity in Tegu Lizards of the Tupinambis teguixin Group (Squamata, Sauria, Teiidae) and the Description of Three New Species.

    PubMed

    Murphy, John C; Jowers, Michael J; Lehtinen, Richard M; Charles, Stevland P; Colli, Guarino R; Peres, Ayrton K; Hendry, Catriona R; Pyron, R Alexander

    2016-01-01

    Tegus of the genera Tupinambis and Salvator are the largest Neotropical lizards and the most exploited clade of Neotropical reptiles. For three decades more than 34 million tegu skins were in trade, about 1.02 million per year. The genus Tupinambis is distributed in South America east of the Andes, and currently contains four recognized species, three of which are found only in Brazil. However, the type species of the genus, T. teguixin, is known from Bolivia, Brazil, Colombia, Ecuador, French Guyana, Guyana, Peru, Suriname, Trinidad and Tobago, and Venezuela (including the Isla de Margarita). Here we present molecular and morphological evidence that this species is genetically divergent across its range and identify four distinct clades some of which are sympatric. The occurrence of cryptic sympatric species undoubtedly exacerbated the nomenclatural problems of the past. We discuss the species supported by molecular and morphological evidence and increase the number of species in the genus Tupinambis to seven. The four members of the T. teguixin group continue to be confused with Salvator merianae, despite having a distinctly different morphology and reproductive mode. All members of the genus Tupinambis are CITES Appendix II. Yet, they continue to be heavily exploited, under studied, and confused in the minds of the public, conservationists, and scientists.

  7. Two new species of diminutive leaf-litter skinks (Squamata: Scincidae: Tytthoscincus) from Gunung Penrissen, Sarawak, Malaysia (northern Borneo).

    PubMed

    Karin, Benjamin R; Das, Indraneil; Bauer, Aaron M

    2016-03-22

    We describe two new species of skinks from Gunung Penrissen, Sarawak, Malaysia, in northern Borneo, Tytthoscincus batupanggah sp. nov. and T. leproauricularis sp. nov. Morphological and molecular analyses both corroborate the two new species as unique compared to all other Tytthoscincus and additional Sphenomorphus that are candidates for taxonomic placement in the genus Tytthoscincus. Despite their phenotypic similarity and sympatric distribution, a molecular analysis shows that the new species are not sister taxa and exhibit a deep genetic divergence between each of their respective sister taxa. We discuss how historical climatic and geographic processes may have led to the co-distribution of two relatively distantly related phenotypically similar species. In light of these discoveries, we also emphasize the importance of conserving primary montane tropical rainforest for maintaining species diversity.

  8. Influences of sex, ontogeny and body size on the thermal ecology of Liolaemus lutzae (Squamata, Liolaemidae) in a restinga remnant in Southeastern Brazil.

    PubMed

    Maia-Carneiro, Thiago; Rocha, Carlos Frederico Duarte

    2013-01-01

    Variations in body temperature (Tb) of lizards can be partially explained by intrinsic factors such as sex, ontogeny and body size. Liolaemus lutzae is a lizard species restricted to restingas in the Brazilian coast in the state of Rio de Janeiro. Herein, we studied sexual dimorphism and influences of sex, ontogeny, and body size to the Tb of L. lutzae. Adult males were larger than adult females, probably due to both intersexual selection and intra-sexual selection. There was intersexual difference in lizards' Tb (males hotter than females), but Tb did not differ after factored out for the effects of body size. The mean Tb of juvenile lizards was higher than that of adults after factored out for the effect of body mass. It is possible that adults may have excluded juveniles from microhabitats with better thermal regimes. Also, this might have occurred due to requirements of juveniles to maintain high growth rates. Forage searching for prey by juveniles also exposes them to high environmental temperatures. Juveniles also may have higher Tb than co-specific adults (relative to body mass) to favor prey capture. In absolute values, adult lizards tended to use microhabitats with lower temperatures than that used by juveniles, possibly to avoid risks of overheating and death. Body temperature and snout-vent length were positively related, as well as body temperature and body mass, presumably caused by the thermal inertia of the bodies (trend of a body to resist to changes in its temperature). Intrinsic factors such as sex, ontogeny and body size can affect the thermal ecology of L. lutzae, despite coastal habitat features to which they are exposed also influences the body temperature of active lizards in restinga habitats.

  9. A new species of Bachia Gray, 1845 (Squamata: Gymnophthalmidae) from the Eastern Brazilian Cerrado, and data on its ecology, physiology and behavior.

    PubMed

    Teixeira, Mauro; Recoder, Renato Sousa; Camacho, Agustín; De Sena, Marco Aurélio; Navas, Carlos Arturo; Rodrigues, Miguel Trefaut

    2013-02-19

    A new species of Bachia of the bresslaui group, Bachia geralista sp. nov., is described from Planalto dos Gerais, an old and partially dissected plateau extending along the Cerrados of Bahia, Minas Gerais and Tocantins states, Brazil. The new species is morphologically similar to B. bresslaui, with which it has been confused; however head scalation resembles other species from sandy spots within the Cerrado (B. psamophila and B. oxyrhina). Like in B. psamophila and B. oxyrhina, the shovel-shaped snout of the new species is highly prominent, a typical trait of psammophilous habits in other gymnophthalmids. The examination of specimens of B. bresslaui from several populations within the Cerrado revealed great variation among localities, leading to the reidentification of a specimen from Utiariti, Mato Grosso, previously referred to in the literature as the second record of B. bresslaui, as the recently described B. didactyla, suggesting that cryptic diversity might remain still undiscovered within this genus in the Cerrado. Despite occurring in a relatively open Cerrado, thermal physiology of Bachia geralista sp. nov. restricts its occurrence to shaded microhabitats within this habitat.

  10. Cryptic, Sympatric Diversity in Tegu Lizards of the Tupinambis teguixin Group (Squamata, Sauria, Teiidae) and the Description of Three New Species

    PubMed Central

    Jowers, Michael J.; Lehtinen, Richard M.; Charles, Stevland P.; Colli, Guarino R.; Peres, Ayrton K.; Hendry, Catriona R.; Pyron, R. Alexander

    2016-01-01

    Tegus of the genera Tupinambis and Salvator are the largest Neotropical lizards and the most exploited clade of Neotropical reptiles. For three decades more than 34 million tegu skins were in trade, about 1.02 million per year. The genus Tupinambis is distributed in South America east of the Andes, and currently contains four recognized species, three of which are found only in Brazil. However, the type species of the genus, T. teguixin, is known from Bolivia, Brazil, Colombia, Ecuador, French Guyana, Guyana, Peru, Suriname, Trinidad and Tobago, and Venezuela (including the Isla de Margarita). Here we present molecular and morphological evidence that this species is genetically divergent across its range and identify four distinct clades some of which are sympatric. The occurrence of cryptic sympatric species undoubtedly exacerbated the nomenclatural problems of the past. We discuss the species supported by molecular and morphological evidence and increase the number of species in the genus Tupinambis to seven. The four members of the T. teguixin group continue to be confused with Salvator merianae, despite having a distinctly different morphology and reproductive mode. All members of the genus Tupinambis are CITES Appendix II. Yet, they continue to be heavily exploited, under studied, and confused in the minds of the public, conservationists, and scientists. PMID:27487019

  11. Three new karst-dwelling Cnemaspis Strauch, 1887 (Squamata; Gekkoniade) from Peninsular Thailand and the phylogenetic placement of C. punctatonuchalis and C. vandeventeri

    PubMed Central

    Grismer, L. Lee; Aowphol, Anchalee; Aguilar, César A.; Cota, Micheal; Grismer, Marta S.; Murdoch, Matthew L.; Sites Jr, Jack W.

    2017-01-01

    Three new species of Rock Geckos Cnemaspis lineogularis sp. nov., C. phangngaensis sp. nov., and C. thachanaensis sp. nov. of the chanthaburiensis and siamensis groups are described from the Thai portion of the Thai-Malay Peninsula. These new species are distinguished from all other species in their two respective groups based on a unique combination of morphological characteristics, which is further supported by mitochondrial DNA (mtDNA) from the NADH dehydrogenase subunit 2 gene (ND2). Cnemaspis lineogularis sp. nov. is differentiated from all other species in the chanthaburiensis group by having a smaller maximum SVL 38 mm, 13 paravertebral tubercles, enlarged femoral scales, no caudal bands, and a 19.5–23.0% pairwise sequence divergence (ND2). Cnemaspis phangngaensis sp. nov. is differentiated from all other species in the siamensis group by having the unique combination of 10 infralabial scales, four continuous pore-bearing precloacal scales, paravertebral tubercles linearly arranged, lacking tubercles on the lower flanks, having ventrolateral caudal tubercles anteriorly present, caudal tubercles restricted to a single paraveterbral row on each side, a single median row of keeled subcaudals, and a 8.8–25.2% pairwise sequence divergence (ND2). Cnemaspis thachanaensis sp. nov. is distinguished from all other species in the siamensis group by having 10 or 11 supralabial scales 9–11 infralabial scales, paravertebral tubercles linearly arranged, ventrolateral caudal tubercles anteriorly, caudal tubercles restricted to a single paravertebral row on each side, a single median row of keeled subcaudal scales, lacking a single enlarged subcaudal scale row, lacking postcloaclal tubercles in males, the presence of an enlarged submetatarsal scale at the base if the 1st toe, and a 13.4–28.8% pairwise sequence divergence (ND2). The new phylogenetic analyses place C. punctatonuchalis and C. vandeventeri in the siamensis group with C. punctatonuchalis as the sister species to C. huaseesom and C. vandeventeri as the sister species to C. siamensis, corroborating previous hypotheses based on morphology. The discovery of three new karst-dwelling endemics brings the total number of nominal Thai Cnemaspis species to 15 and underscores the need for continued field research in poorly known areas of the Thai-Malay Peninsula, especially those that are threatened and often overlooked as biodiversity hot spots. PMID:28149678

  12. Integrative taxonomy and preliminary assessment of species limits in the Liolaemus walkeri complex (Squamata, Liolaemidae) with descriptions of three new species from Peru

    PubMed Central

    Aguilar, César; Wood Jr, Perry L.; Cusi, Juan C.; Guzmán, Alfredo; Huari, Frank; Lundberg, Mikael; Mortensen, Emma; Ramírez, César; Robles, Daniel; Suárez, Juana; Ticona, Andres; Vargas, Víctor J.; Venegas, Pablo J.; Sites Jr, Jack W.

    2013-01-01

    Abstract Species delimitation studies based on integrative taxonomic approaches have received considerable attention in the last few years, and have provided the strongest hypotheses of species boundaries. We used three lines of evidence (molecular, morphological, and niche envelopes) to test for species boundaries in Peruvian populations of the Liolaemus walkeri complex. Our results show that different lines of evidence and analyses are congruent in different combinations, for unambiguous delimitation of three lineages that were “hidden” within known species, and now deserve species status. Our phylogenetic analysis shows that L. walkeri, L. tacnae and the three new species are strongly separated from other species assigned to the alticolor-bibronii group. Few conventional morphological characters distinguish the new species from closely related taxa and this highlights the need to integrate other sources of data to erect strong hypothesis of species limits. A taxonomic key for known Peruvian species of the subgenus Lioalemus is provided. PMID:24453545

  13. A relict lineage and new species of green palm-pitviper (Squamata, Viperidae, Bothriechis) from the Chortís Highlands of Mesoamerica.

    PubMed

    Townsend, Josiah H; Medina-Flores, Melissa; Wilson, Larry David; Jadin, Robert C; Austin, James D

    2013-01-01

    A new species of palm-pitviper of the genus Bothriechis is described from Refugio de Vida Silvestre Texíguat in northern Honduras. The new species differs from congeners by having 19 dorsal scale rows at midbody, a bright green dorsal coloration in adults, the prelacunal scale fused to the second supralabial, and in representing a northern lineage that is sister to Bothriechis lateralis, which is distributed in Costa Rica and western Panama and is isolated from the new taxon by the Nicaraguan Depression. This represents the 15th endemic species occurring in Refugio de Vida Silvestre Texíguat, one of the richest herpetofaunal sites in Honduras, itself being the country with the highest degree of herpetofaunal endemism in Central America. We name this new species in honor of a Honduran conservationist slain in fighting against illegal logging, highlighting the sacrifices of rural activists in battling these issues and the critical importance of conservation in these areas.

  14. Microanatomical and Histological Features in the Long Bones of Mosasaurine Mosasaurs (Reptilia, Squamata) – Implications for Aquatic Adaptation and Growth Rates

    PubMed Central

    Houssaye, Alexandra; Lindgren, Johan; Pellegrini, Rodrigo; Lee, Andrew H.; Germain, Damien; Polcyn, Michael J.

    2013-01-01

    Background During their evolution in the Late Cretaceous, mosasauroids attained a worldwide distribution, accompanied by a marked increase in body size and open ocean adaptations. This transition from land-dwellers to highly marine-adapted forms is readily apparent not only at the gross anatomic level but also in their inner bone architecture, which underwent profound modifications. Methodology/Principal Findings The present contribution describes, both qualitatively and quantitatively, the internal organization (microanatomy) and tissue types and characteristics (histology) of propodial and epipodial bones in one lineage of mosasauroids; i.e., the subfamily Mosasaurinae. By using microanatomical and histological data from limb bones in combination with recently acquired knowledge on the inner structure of ribs and vertebrae, and through comparisons with extant squamates and semi-aquatic to fully marine amniotes, we infer possible implications on mosasaurine evolution, aquatic adaptation, growth rates, and basal metabolic rates. Notably, we observe the occurrence of an unusual type of parallel-fibered bone, with large and randomly shaped osteocyte lacunae (otherwise typical of fibrous bone) and particular microanatomical features in Dallasaurus, which displays, rather than a spongious inner organization, bone mass increase in its humeri and a tubular organization in its femora and ribs. Conclusions/Significance The dominance of an unusual type of parallel-fibered bone suggests growth rates and, by extension, basal metabolic rates intermediate between that of the extant leatherback turtle, Dermochelys, and those suggested for plesiosaur and ichthyosaur reptiles. Moreover, the microanatomical features of the relatively primitive genus Dallasaurus differ from those of more derived mosasaurines, indicating an intermediate stage of adaptation for a marine existence. The more complete image of the various microanatomical trends observed in mosasaurine skeletal elements supports the evolutionary convergence between this lineage of secondarily aquatically adapted squamates and cetaceans in the ecological transition from a coastal to a pelagic lifestyle. PMID:24146919

  15. A retrospective study of mortality in varanid lizards (Reptilia: Squamata: Varanidae) at the Bronx Zoo: implications for husbandry and reproductive management in zoos.

    PubMed

    Mendyk, Robert W; Newton, Alisa L; Baumer, Megan

    2013-03-01

    Varanid lizards have been maintained in zoological parks for more than a century, yet few studies to date have attempted to pinpoint significant health issues affecting their management or areas of captive husbandry that are in need of improvement. In an effort to identify and better understand some of the husbandry-related challenges and health issues specifically affecting varanids in zoos, this study examined mortality in 16 species maintained at the Bronx Zoo between 1968 and 2009. Out of 108 records reviewed, complete necropsy reports were available for 85 individuals. Infection-related processes including bacterial (15.3%), protozoal (12.9%), nematode (9.4%), and fungal (3.5%) infections accounted for the greatest number of deaths (47.1%). Noninfectious diseases including female reproductive disorders (7.1%), neoplasia (7.1%), gout (10.8%), and hemipenal prolapse (1.3%) accounted for 29.4% of deaths. Multiple disease agents were responsible for 5.9% of deaths, and a cause for death could not be determined for 17.7% of individuals. Reproductive complications accounted for 11.5% of female deaths, but were identified in 23.1% of females. Although not necessarily the cause for death, gout was present in 18.8% of individuals. Differences in mortality between species, genders, and origin (captive-bred vs. wild-caught) were also evaluated. The results of this study corroborate earlier findings that identify bacterial infections, neoplasia, female reproductive disorders, gout, and endoparasitism as major sources of mortality in captive varanids. In light of these results, we discuss potential etiologies and offer recommendations for improving captive management practices in zoos.

  16. A new genus and species of gekkonid lizard (Squamata: Gekkota: Gekkonidae) from Hormozgan Province with a revised key to gekkonid genera of Iran.

    PubMed

    Safaei-Mahroo, Barbod; Ghaffari, Hanyeh; Anderson, Steven C

    2016-05-10

    We describe a new genus and species of gekkonid from two gravid specimens which were found within Koh-e Homag Protected Area, Hormozgan Province, southern Iran. The genus Parsigecko gen. nov. can be distinguished from other genera of Middle East Gekkonidae by a combination of the following characteristics: digits not dilated, dorsal tail covered with small scales without any tubercles or keels, having two strong keeled and pointed scales on each side of each annulus. Parsigecko ziaiei sp. nov. is a ground-dwelling lizard. The new species was found in the Zagros Mountain forest steppe patch with scattered wild pistachio trees and mountain almond shrubs surrounded by South Iran Nubo-Sindian desert and semi-desert habitat in the south of Iran. The genus is the 13th gekkonid genus known from Iran, and the only gekkonid genus endemic to the Zagros Mountains. A key to the genera of the Gekkonidae in Iran is provided.

  17. A cryptic palm-pitviper species (Squamata: Viperidae: Bothriechis) from the Costa Rican highlands, with notes on the variation within B. nigroviridis.

    PubMed

    Doan, Tiffany M; Mason, Andrew J; Castoe, Todd A; Sasa, Mahmood; Parkinson, Christopher L

    2016-07-15

    Middle America is one of the most biodiverse regions in the world, harboring an exceptional number of rare and endemic species. This is especially true of Middle American cloud forests, where montane specialists occupy restricted, high-elevation ranges making them attractive candidates for investigating historical biogeography and speciation. One such highland-restricted species, the black speckled palm-pitviper (Bothriechis nigroviridis), occupies the Central, Tilarán, and Talamanca Cordilleras in Costa Rica and Panama. In this study, we investigate the genetic and morphological variation among populations of B. nigroviridis by inferring a multilocus phylogeny (21 individuals) and analyzing meristic scale characters with a principal component analysis (64 individuals). We find B. nigroviridis sensu stricto to be composed of two deeply divergent lineages, one with a restricted range in the northern and central Cordillera Talamanca and the other ranging throughout the Central, Tilarán, and Talamanca Cordilleras. Furthermore, these two lineages are morphologically distinct, with previously unrecognized differences in several characters allowing us to name and diagnose a new species B. nubestris sp. nov. We also examine the genetic and morphological variation within B. nigroviridis and discuss biogeographic hypotheses that may have led to the diversification of Bothriechis lineages.

  18. How does a viviparous semifossorial lizard reproduce? Ophiodes intermedius (Squamata: Anguidae) from subtropical climate in the Wet Chaco region of Argentina.

    PubMed

    Ortiz, Martín A; Boretto, Jorgelina M; Ibargüengoytía, Nora R

    2017-01-16

    The best predictors of reproductive patterns are commonly associated with climate factors, but evolutionary history also plays an important role. The semifossorial and viviparous lizard Ophiodes intermedius from the Wet Chaco region of Argentina showed an annual cycle with asynchrony between males and females and an unusual pattern for subtropical climates, with vitellogenesis beginning in autumn, ovulation and copulation in spring, and births occurring in summer. Males exhibited annual variation of testicular size associated with spermatogenic activity, reaching their maximum gonadal activity in late summer (March), but sperm storage in the epididymis and/or deferent duct occurred throughout the year. Females showed an extended reproductive cycle beginning in mid-autumn (May) with vitellogenesis and finishing with births from late spring to mid-summer (December to February). Litter size varied from 4 to 9 offspring. Females reached sexual maturity at a larger snout-vent length and, overall, showed greater body size than males, while males exhibited larger heads than females. Fat body cycles indicated that females use lipid reserves to support vitellogenesis and embryo development, while males allocate lipid resources to the search for females, courtship and copulation rather than to gametogenesis. Ophiodes intermedius differed from other species of the genus in litter size, gestation period, timing of birth and the minimum size at sexual maturity, probably as a result of the influence of ecological, historical and phylogenetic factors.

  19. Two new endemic species of Ameiva (Squamata: Teiidae) from the dry forest of northwestern Peru and additional information on Ameiva concolor Ruthven, 1924.

    PubMed

    Koch, Claudia; Venegas, Pablo J; Rödder, Dennis; Flecks, Morris; Böhme, Wolfgang

    2013-12-04

    We describe two new species of Ameiva Meyer, 1795 from the dry forest of the Northern Peruvian Andes. The new species Ameiva nodam sp. nov. and Ameiva aggerecusans sp. nov. share a divided frontal plate and are differentiated from each other and from their congeners based on genetic (12S and 16S rRNA genes) and morphological characteristics. A. nodam sp. nov. has dilated postbrachials, a maximum known snout-vent length of 101 mm, 10 longitudinal rows of ventral plates, 86-113 midbody granules, 25-35 lamellae under the fourth toe, and a color pattern with 5 longitudinal yellow stripes on the dorsum. Ameiva aggerecusans sp. nov. has not or only hardly dilated postbrachials, a maximum known snout-vent length of 99.3 mm, 10-12 longitudinal rows of ventral plates, 73-92 midbody granules, 31-39 lamellae under the fourth toe, and the females and juveniles of the species normally exhibit a cream-colored vertebral stripe on a dark dorsum ground color. We provide information on the intraspecific variation and distribution of A. concolor. Furthermore, we provide information on the environmental niches of the taxa and test for niche conservatism. 

  20. So Far Away, Yet So Close: Strong Genetic Structure in Homonota uruguayensis (Squamata, Phyllodactylidae), a Species with Restricted Geographic Distribution in the Brazilian and Uruguayan Pampas

    PubMed Central

    Felappi, Jéssica F.; Vieira, Renata C.; Fagundes, Nelson J. R.; Verrastro, Laura V.

    2015-01-01

    The Pampas is a biologically rich South American biome, but is poorly represented in phylogeographic studies. While the Pleistocene glacial cycles may have affected the evolutionary history of species distributed in forested biomes, little is known about their effects on the habitats that remained stable through glacial cycles. The South American Pampas have been covered by grasslands during both glacial and interglacial periods and therefore represent an interesting system to test whether the genetic structure in such environments is less pronounced. In this study, we sampled Pampean populations of Homonota uruguayensis from Southern Brazil and Uruguay to assess the tempo and mode of population divergence, using both morphological measurements and molecular markers. Our results indicate that, in spite of its narrow geographic distribution, populations of H. uruguayensis show high levels of genetic structure. We found four major well-supported mtDNA clades with strong geographic associations. Estimates of their divergence times fell between 3.16 and 1.82 million years before the present. Populations from the central portion of the species distribution, on the border between Uruguay and Brazil, have high genetic diversity and may have undergone a population expansion approximately 250,000 years before the present. The high degree of genetic structure is reflected in the analyses of morphological characters, and most individuals could be correctly assigned to their parental population based on morphology alone. Finally, we discuss the biogeographic and conservation implications of these findings. PMID:25692471

  1. Phylogenomics and species delimitation in the knob-scaled lizards of the genus Xenosaurus (Squamata: Xenosauridae) using ddRADseq data reveal a substantial underestimation of diversity.

    PubMed

    Nieto-Montes de Oca, Adrián; Barley, Anthony J; Meza-Lázaro, Rubi N; García-Vázquez, Uri O; Zamora-Abrego, Joan G; Thomson, Robert C; Leaché, Adam D

    2017-01-01

    Middle American knob-scaled lizards of the genus Xenosaurus are a unique radiation of viviparous species that are generally characterized by a flattened body shape and a crevice-dwelling ecology. Only eight species of Xenosaurus, one of them with five subspecies (X. grandis), have been formally described. However, species limits within Xenosaurus have never been examined using molecular data, and no complete phylogeny of the genus has been published. Here, we used ddRADseq data from all of the described and potentially undescribed taxa of Xenosaurus to investigate species limits, and to obtain a phylogenetic hypothesis for the genus. We analyzed the data using a variety of phylogenetic models, and were able to reconstruct a well-resolved and generally well-supported phylogeny for this group. We found Xenosaurus to be composed of four major, allopatric clades concordant with geography. The first and second clades that branch off the tree are distributed on the Atlantic slopes of the Sierra Madre Oriental and are composed of X. mendozai, X. platyceps, and X. newmanorum, and X. tzacualtipantecus and an undescribed species from Puebla, respectively. The third clade is distributed from the Atlantic slopes of the Mexican Transvolcanic Belt in west-central Veracruz south to the Pacific slopes of the Sierra Madre del Sur in Guerrero and Oaxaca, and is composed of X. g. grandis, X. rectocollaris, X. phalaroanthereon, X. g. agrenon, X. penai, and four undescribed species from Oaxaca. The last clade is composed of the four taxa that are geographically closest to the Isthmus of Tehuantepec (X. g. arboreus, X. g. rackhami, X. g. sanmartinensis, and an undescribed species from Oaxaca). We also utilized a variety of molecular species delimitation approaches, including analyses with GMYC, PTP, BPP, and BFD(∗), which suggested that species diversity in Xenosaurus is at least 30% higher than currently estimated.

  2. A preliminary assessment of the Nactus pelagicus species group (Squamata: Gekkonidae) in New Guinea and a new species from the Admiralty Islands

    USGS Publications Warehouse

    Zug, George R.; Fisher, Robert N.

    2012-01-01

    The Slender-toed Geckos (Nactus) currently have four recognized species in New Guinea, and these species divide into two sister clades: a pelagicus clade and a vankampeni clade (Heinicke et al. 2010). The latter contains three dwarf species. The former consists of five bisexual populations, of which numerous New Guinea populations are uncharacterized nomenclaturally and lumped under the epithet ‘pelagicus.’ This report and description of a new species of the pelagicus group from Manus Island in the Admiralty Islands encourages us to offer a preliminary assessment of morphology and diversity in New Guinea ‘pelagicus’ populations.

  3. Integrative taxonomy and preliminary assessment of species limits in the Liolaemus walkeri complex (Squamata, Liolaemidae) with descriptions of three new species from Peru.

    PubMed

    Aguilar, César; Wood, Perry L; Cusi, Juan C; Guzmán, Alfredo; Huari, Frank; Lundberg, Mikael; Mortensen, Emma; Ramírez, César; Robles, Daniel; Suárez, Juana; Ticona, Andres; Vargas, Víctor J; Venegas, Pablo J; Sites, Jack W

    2013-12-18

    Species delimitation studies based on integrative taxonomic approaches have received considerable attention in the last few years, and have provided the strongest hypotheses of species boundaries. We used three lines of evidence (molecular, morphological, and niche envelopes) to test for species boundaries in Peruvian populations of the Liolaemus walkeri complex. Our results show that different lines of evidence and analyses are congruent in different combinations, for unambiguous delimitation of three lineages that were "hidden" within known species, and now deserve species status. Our phylogenetic analysis shows that L. walkeri, L. tacnae and the three new species are strongly separated from other species assigned to the alticolor-bibronii group. Few conventional morphological characters distinguish the new species from closely related taxa and this highlights the need to integrate other sources of data to erect strong hypothesis of species limits. A taxonomic key for known Peruvian species of the subgenus Lioalemus is provided.

  4. Additions to Philippine Slender Skinks of the Brachymeles bonitae Complex (Reptilia: Squamata: Scincidae) II: a new species from the northern Philippines.

    PubMed

    Siler, Cameron D; Davis, Drew R; Freitas, Elyse S; Huron, Nicholas A; Geheber, Aaron D; Watters, Jessa L; Penrod, Michelle L; Papeș, Monica; Amrein, Andrew; Anwar, Alyssa; Cooper, Dontae; Hein, Tucker; Manning, Annalisa; Patel, Neeral; Pinaroc, Lauren; Diesmos, Arvin C; Diesmos, Mae L; Oliveros, Carl H; Brown, Rafe M

    2016-06-28

    We describe a new digitless scincid lizard of the genus Brachymeles from northern Luzon and Camiguin Norte islands in the Philippines. This species belongs to the Brachymeles bonitae Complex, and both molecular and morphological data confirm that this species is distinct from all other congeners. Formerly considered to be a single widespread species, this group of species has been the focus of recent systematic reviews. Here we describe a new species in the B. bonitae Complex, recognized currently to constitute five species. Brachymeles ilocandia sp. nov. is the second digitless and the seventeenth non-pentadactyl species in genus. The description of this species brings the total number of species in the genus to 40, and provides new insight into unique distribution patterns of species of the northern Philippines.

  5. A review of Cordylus machadoi (Squamata: Cordylidae) in southwestern Angola, with the description of a new species from the Pro-Namib desert.

    PubMed

    Stanley, Edward L; Ceríaco, Luis M P; Bandeira, Suzana; Valerio, Hilaria; Bates, Michael F; Branch, William R

    2016-01-07

    The girdled lizard genus Cordylus is represented in Angola by two species, Cordylus angolensis and C. machadoi, separated from their nearest congeners by over 700 km. Here we describe a new species, Cordylus namakuiyus sp. nov., endemic to the arid lowlands west of the southern Angolan escarpment. Phylogenetic analysis using three mitochondrial and eight nuclear genes shows that the low-elevation forms and the proximate, high-elevation species C. machadoi are genetically divergent and reciprocally monophyletic, and together form the earliest diverging lineage of the northern Cordylus clade. Morphological data, collected using computed tomography and traditional techniques (scalation and morphology), identify consistent phenotypic differences between these high- and low-elevation species and allows for a detailed description of the osteology and osteodermal arrangements of the new species. A series of 50 specimens, collected during the 1925 Vernay expedition to southwestern Angola and housed at the American Museum of Natural History, are assigned to the new species, although the identity of Cordylus from northern Namibia remains ambiguous and requires further investigation.

  6. Microendemicity in the northern Hajar Mountains of Oman and the United Arab Emirates with the description of two new species of geckos of the genus Asaccus (Squamata: Phyllodactylidae)

    PubMed Central

    Jayasinghe, Sithum; Wilms, Thomas; Els, Johannes

    2016-01-01

    Background The Hajar Mountains of Oman and the United Arab Emirates (UAE) is the highest mountain range in Eastern Arabia. As a result of their old geological origin, geographical isolation, complex topography and local climate, these mountains provide an important refuge for endemic and relict species of plants and animals with strong Indo-Iranian affinities. Among vertebrates, the rock climbing nocturnal geckos of the genus Asaccus represent the genus with the highest number of endemic species in the Hajar Mountains. Recent taxonomic studies on the Zagros populations of Asaccus have shown that this genus is much richer than it was previously thought and preliminary morphological and molecular data suggest that its diversity in Arabia may also be underestimated. Methods A total of 83 specimens originally classified as Asaccus caudivolvulus (including specimens of the two new species described herein), six other Asaccus species from the Hajar and the Zagros Mountains and two representatives of the genus Haemodracon were sequenced for up to 2,311 base pairs including the mitochondrial 12S and cytb and the nuclear c-mos, MC1R and ACM4 genes. Phylogenetic relationships were inferred using both Bayesian and maximum-likelihood approaches and the former method was also used to calibrate the phylogenetic tree. Haplotype networks and phylogenetic trees were inferred from the phased nuclear genes only. Sixty-one alcohol-preserved adult specimens originally classified as Asaccus caudivolvulus from the northern Hajar Mountains were examined for 13 morphometric and the five meristic variables using multivariate methods and were also used to diagnose and describe the two new species. Results The results of the molecular and morphological analyses indicate that the species originally classified as Asaccus caudivolvulus is, in fact, an assemblage of three different species that started diversifying during the Mid-Miocene. The molecular phylogenies consistently recovered the Hajar endemic A. montanus as sister taxon to all the other Asaccus species included in the analyses, rendering the Arabian species of Asaccus polyphyletic. Discussion Using this integrative approach we have uncovered a very old diversification event that has resulted in a case of microendemicity, where three morphologically and ecologically similar medium-sized lizard species coexist in a very short and narrow mountain stretch. Asaccus caudivolvulus is restricted to a small coastal area of the UAE and at risk from heavy development, while the two new species described herein are widely distributed across the northern tip of the Hajar Mountains and seem to segregate in altitude when found in close proximity in the Musandam Peninsula (Oman). Similarly to other integrative analyses of Hajar reptiles, this study highlights the high level of diversity and endemicity of this arid mountain range, underscoring its status as one of the top hotspots of reptile diversity in Arabia. PMID:27602305

  7. A new species of lizard Placosoma Tschudi, 1847 (Squamata: Gymnophthalmidae) from the relictual forest mountains of the State of Ceará, Brazil.

    PubMed

    Borges-Nojosa, Diva Maria; Caramaschi, Ulisses; Rodrigues, Miguel Trefaut

    2016-09-19

    A new species of Placosoma Tschudi, 1847, until now restricted to the Atlantic Forest areas of southeastern Brazil is        described based on specimens obtained about 1700 km north to the current distribution of the genus. Placosoma limaverdorum spec. nov. is apparently endemic to three "brejos-de-altitude", relictual forest mountains surrounded by dry Caatingas, in the State of Ceará, northeastern Brazil. It differs from their congeners by the presence of an undivided transparent palpebral disk, a divided nasal scale with a central nostril, a deep tympanic recess, a distinctive and thin light vertebral stripe on the dorsal surface of the head, body and tail, femoral pores present only in males (21-26), preanal pores absent and additionally by having 21-24 rows of transverse ventral scales, 34-38 dorsals, dorsal, lateral and ventral scales smooth, dorsal scales quadrangular, longer than wide, except in the neck region, where they are wider than long.

  8. A new blue-tailed Monitor lizard (Reptilia, Squamata, Varanus) of the Varanus indicus group from Mussau Island, Papua New Guinea

    PubMed Central

    Weijola, Valter; Donnellan, Stephen C.; Lindqvist, Christer

    2016-01-01

    Abstract We describe a new species of Varanus from Mussau Island, north-east of New Guinea. The new species is a member of the Varanus indicus species group and is distinguished from all other members by both morphological and molecular genetic characters. It is the third species of Varanus reported from the Bismarck Archipelago and the first record of a yellow tongued member of the Varanus indicus species group from a remote oceanic island. The herpetofauna of Mussau Island has not been well studied but the discovery of this new species is in accordance with recent findings indicating that the island may harbor several unknown endemic vertebrates. The distribution of the closely related Varanus finschi is also discussed in the light of recent fieldwork and a review of old records. PMID:27103877

  9. Radiation, multiple dispersal and parallelism in the skinks, Chalcides and Sphenops (Squamata: Scincidae), with comments on Scincus and Scincopus and the age of the Sahara Desert.

    PubMed

    Carranza, S; Arnold, E N; Geniez, Ph; Roca, J; Mateo, J A

    2008-03-01

    Phylogenetic analysis using up to 1325 base pairs of mitochondrial DNA from 179 specimens and 30 species of Chalcides, Sphenops, Eumeces, Scincopus and Scincus indicates that Sphenops arose twice independently within Chalcides. It is consequently synonymized with that genus. Chalcides in this broader sense originated in Morocco, diversifying into four main clades about 10 Ma, after which some of its lineages dispersed widely to cover an area 40 times as large. Two separate lineages invaded the Canary Islands and at least five main lineages colonized southern Europe. At least five more spread across northern Africa, one extending into southwest Asia. Elongate bodies with reduced limbs have evolved at least four times in Chalcides, mesic 'grass-swimmers' being produced in one case and extensive adaptation to life in loose desert sand in two others. In clade, Chalcides striatus colonized SW Europe from NW Africa 2.6 Ma and C. chalcides mainland Italy 1.4 Ma, both invasions being across water, while C. c. vittatus reached Sardinia more recently, perhaps anthropogenically, and C. guentheri spread 1200km further east to Israel. C. minutus is a composite, with individuals from the type locality forming a long independent lineage and the remaining ones investigated being most closely related to C. mertensi. In the Northern clade, C. boulengeri and C. sepsoides spread east through sandy habitats north of the Sahara about 5 Ma, the latter reaching Egypt. C. bedriagai invaded Spain around the same time, perhaps during the Messinian period when the Mediterranean was dry, and shows considerable diversification. Although it is currently recognized as one species, the C. ocellatus clade exhibits as much phylogenetic depth as the other main clades of Chalcides, having at least six main lineages. These have independently invaded Malta and Sardinia from Tunisia and also southwest Arabia C. o. humilis appears to have spread over 4000 km through the Sahel, south of the Sahara quite recently, perhaps in the Pleistocene. In the Western clade of Chalcides, C. delislei appears to have dispersed in a similar way. There were also two invasions of the Canary Islands: one around 5 Ma by C. simonyi, and the other about 7 Ma by the ancestor of C. viridanus+C. sexlineatus. C. montanus was believed to be related to C. lanzai of the Northern clade, but in the mtDNA tree it is placed within C. polylepis of the Western clade, although this may possibly be an artifact of introgression. The Eumeces schneideri group, Scincopus and Scincus form a clade separate from Chalcides. Within this clade, the geographically disjunct E. schneideri group is paraphyletic. One of its members, E. algeriensis is the sister taxon to Scincopus, and Scincus may also be related to these taxa. The phylogeny suggests Scincopus entered desert conditions in Africa, up to 9.6 Ma and the same may have been true of Scincus up to 11.7 Ma. Scincus appears to have diversified and spread into Arabia around 6 Ma. Dates of origin and divergence of these skinks, desert Chalcides and other squamates agree with recent geological evidence that the Sahara is at least 5-7 My old. The subspecies Chalcides viridanus coeruleopunctatus is upgraded to the species level as C. coeruleopunctatus stat nov., on the basis of its large genetic divergence from C. v. viridanus.

  10. A phylogeny of the only ground-dwelling radiation of Cyrtodactylus (Squamata, Gekkonidae): diversification of Geckoella across peninsular India and Sri Lanka.

    PubMed

    Agarwal, Ishan; Karanth, K Praveen

    2015-01-01

    The subgenus Geckoella, the only ground-dwelling radiation within Cyrtodactylus, closely overlaps in distribution with brookii group Hemidactylus in peninsular India and Sri Lanka. Both groups have Oligocene origins, the latter with over thrice as many described species. The striking difference in species richness led us to believe that Geckoella diversity is underestimated, and we sampled for Geckoella across peninsular India. A multi-locus phylogeny reveals Geckoella diversity is hugely underestimated, with at least seven undescribed species, doubling previously known richness. Strikingly, the new species correspond to cryptic lineages within described Indian species (complexes); a number of these endemic lineages from the hills of peninsular India outside the Western Ghats, highlighting the undocumented diversity of the Indian dry zone. The Geckoella phylogeny demonstrates deep splits between the Indian species and Sri Lankan G. triedrus, and between Indian dry and wet zone clades, dating back to the late Oligocene. Geckoella and brookii group Hemidactylus show contrasting diversification patterns. Geckoella shows signals of niche conservatism and appears to have retained its ancestral forest habitat. The late Miocene burst in speciation in Geckoella may be linked to the expansion of rain forests during the mid-Miocene climatic optimum and subsequent fragmentation with increasing late Miocene aridification.

  11. Differentiation of sex chromosomes and karyotypic evolution in the eye-lid geckos (Squamata: Gekkota: Eublepharidae), a group with different modes of sex determination.

    PubMed

    Pokorná, Martina; Rábová, Marie; Ráb, Petr; Ferguson-Smith, Malcolm A; Rens, Willem; Kratochvíl, Lukáš

    2010-11-01

    The eyelid geckos (family Eublepharidae) include both species with temperature-dependent sex determination and species where genotypic sex determination (GSD) was suggested based on the observation of equal sex ratios at several incubation temperatures. In this study, we present data on karyotypes and chromosomal characteristics in 12 species (Aeluroscalabotes felinus, Coleonyx brevis, Coleonyx elegans, Coleonyx variegatus, Eublepharis angramainyu, Eublepharis macularius, Goniurosaurus araneus, Goniurosaurus lichtenfelderi, Goniurosaurus luii, Goniurosaurus splendens, Hemitheconyx caudicinctus, and Holodactylus africanus) covering all genera of the family, and search for the presence of heteromorphic sex chromosomes. Phylogenetic mapping of chromosomal changes showed a long evolutionary stasis of karyotypes with all acrocentric chromosomes followed by numerous chromosomal rearrangements in the ancestors of two lineages. We have found heteromorphic sex chromosomes in only one species, which suggests that sex chromosomes in most GSD species of the eyelid geckos are not morphologically differentiated. The sexual difference in karyotype was detected only in C. elegans which has a multiple sex chromosome system (X(1)X(2)Y). The metacentric Y chromosome evolved most likely via centric fusion of two acrocentric chromosomes involving loss of interstitial telomeric sequences. We conclude that the eyelid geckos exhibit diversity in sex determination ranging from the absence of any sexual differences to heteromorphic sex chromosomes, which makes them an interesting system for exploring the evolutionary origin of sexually dimorphic genomes.

  12. Phylogenetic relationships, genetic divergence, historical biogeography and conservation of an endangered gecko, Goniurosaurus kuroiwae (Squamata: Eublepharidae), from the Central Ryukyus, Japan.

    PubMed

    Honda, Masanao; Kurita, Takaki; Toda, Mamoru; Ota, Hidetoshi

    2014-05-01

    The Kuroiwa's eyelid gecko Goniurosaurus kuroiwae is an endangered species in a state of relict endemism in the Central Ryukyus, Japan, and is divided into five subspecies. We analyzed variations in sequence data for approximately 1900 base positions of mitochondrial 12S and 16S rRNA, and cytochrome b genes from samples representing all recognized subspecies of G. kuroiwae together with those from congeneric species in order to test the relevant previous phylogenetic hypotheses and discuss biogeographical implications in the degree and pattern of genetic divergence within G. kuroiwae. Our results, while confirming a previous molecular phylogenetic hypothesis proposed on the basis of much smaller data set, negate the relationships hypothesized on morphological grounds by explicitly supporting: 1) the primary dichotomy, with substantial genetic divergence, between G. k. splendens from the Amami Island Group and the remaining subspecies all from the Okinawa Island Group; and 2) the presence of at least six independent lineages within the latter, indicating non-monophyly for two of the subspecies, G. k. kuroiwae and G. k. orientalis, in the current taxonomic definitions. The marked genetic divergence between populations of the two island groups seems to have initiated in the middle Miocene, i.e., prior to formation of straits that have consistently been separating these two island groups since the early Pleistocene. All populations of G. kuroiwae are regarded as endangered from the viewpoint of conservation genetics.

  13. Conservation assessments in climate change scenarios: spatial perspectives for present and future in two Pristidactylus (Squamata: Leiosauridae) lizards from Argentina.

    PubMed

    Minoli, Ignacio; Avila, Luciano Javier

    2017-02-26

    The consequences of global climate change can already be seen in many physical and biological systems and these effects could change the distribution of suitable areas for a wide variety of organisms to the middle of this century. We analyzed the current habitat use and we projected the suitable area of present conditions into the geographical space of future scenarios (2050), to assess and quantify whether future climate change would affect the distribution and size of suitable environments in two Pristidactylus lizard species. Comparing the habitat use and future forecasts of the two studied species, P. achalensis showed a more restricted use of available resource units (RUs) and a moderate reduction of the potential future area. On the contrary, P. nigroiugulus uses more available RUs and has a considerable area decrease for both future scenarios. These results suggest that both species have a moderately different trend towards reducing available area of suitable habitats, the persistent localities for both 2050 CO2 concentration models, and in the available RUs used. We discussed the relation between size and use of the current habitat, changes in future projections along with the protected areas from present-future and the usefulness of these results in conservation plans. This work illustrates how ectothermic organisms might have to face major changes in their availability suitable areas as a consequence of the effect of future climate change.

  14. Evolutionary dynamics of two satellite DNA families in rock lizards of the genus Iberolacerta (Squamata, Lacertidae): different histories but common traits.

    PubMed

    Rojo, Verónica; Martínez-Lage, Andrés; Giovannotti, Massimo; González-Tizón, Ana M; Nisi Cerioni, Paola; Caputo Barucchi, Vincenzo; Galán, Pedro; Olmo, Ettore; Naveira, Horacio

    2015-09-01

    Satellite DNAs compose a large portion of all higher eukaryotic genomes. The turnover of these highly repetitive sequences is an important element in genome organization and evolution. However, information about the structure and dynamics of reptilian satellite DNA is still scarce. Two satellite DNA families, HindIII and TaqI, have been previously characterized in four species of the genus Iberolacerta. These families showed different chromosomal locations, abundances, and evolutionary rates. Here, we extend the study of both satellite DNAs (satDNAs) to the remaining Iberolacerta species, with the aim to investigate the patterns of variability and factors influencing the evolution of these repetitive sequences. Our results revealed disparate patterns but also common traits in the evolutionary histories of these satellite families: (i) each satellite DNA is made up of a library of monomer variants or subfamilies shared by related species; (ii) species-specific profiles of satellite repeats are shaped by expansions and/or contractions of different variants from the library; (iii) different turnover rates, even among closely related species, result in great differences in overall sequence homogeneity and in concerted or non-concerted evolution patterns, which may not reflect the phylogenetic relationships among taxa. Contrasting turnover rates are possibly related to genomic constraints such as karyotype architecture and the interspersed organization of diverging repeat variants in satellite arrays. Moreover, rapid changes in copy number, especially in the centromeric HindIII satDNA, may have been associated with chromosomal rearrangements and even contributed to speciation within Iberolacerta.

  15. Body location and tail regeneration effects on osteoderms morphology-are they useful tools for systematic, paleontology, and skeletochronology in diploglossine lizards (squamata, anguidae)?

    PubMed

    Bochaton, Corentin; De Buffrenil, Vivian; Lemoine, Michel; Bailon, Salvador; Ineich, Ivan

    2015-11-01

    Although diploglossine osteoderms were mentioned in several systematic and paleontological studies, their morphological variability in single specimens or within species remains paradoxically undescribed. This is mainly the effect of the lack of attention paid hitherto to the morphological and histological characteristics of the tail osteoderms. This study demonstrated that a previously undescribed morphological variability exists in these osteoderms, especially in those resulting from tail regeneration. Indeed, regenerated osteoderms display a plesiomorphic anguid morphology that was previously considered to be absent in Diploglossinae. We also provide the first histological description of diploglossine osteoderms and new information about the obvious differences in growth dynamic between regenerated and nonregenerated osteoderms. These new data raise questions about the usefulness of diploglossine osteoderms in systematic, paleontological, and skeletochronological studies. Our study shows that the exact position on the trunk or on a regenerated or nonregenerated tail of each studied osteoderm must be known in order to avoid mistakes related to their important interspecies and intraspecies variability.

  16. A simple non-invasive protocol to establish primary cell lines from tail and toe explants for cytogenetic studies in Australian dragon lizards (Squamata: Agamidae)

    PubMed Central

    O’Meally, Denis; Quinn, Alexander E.; Sarre, Stephen D.; Georges, Arthur; Marshall Graves, Jennifer A.

    2009-01-01

    Primary cell lines were established from cultures of tail and toe clips of five species of Australian dragon lizards: Tympanocryptis pinguicolla, Tympanocryptis sp., Ctenophorus fordi, Amphibolurus norrisi and Pogona vitticeps. The start of exponential cell growth ranged from 1 to 5 weeks. Cultures from all specimens had fibroblastic morphology. Cell lines were propagated continuously up to ten passages, cryopreserved and recovered successfully. We found no reduction in cell viability after short term (<6 months) storage at −80 °C. Mitotic metaphase chromosomes were harvested from these cell lines and used in differential staining, banding and fluorescent in situ hybridisation. Cell lines maintained normal diploidy in all species. This study reports a simple non-invasive method for establishing primary cell lines from Australian dragon lizards without sacrifice. The method is likely to be applicable to a range of species. Such cell lines provide a virtually unlimited source of material for cytogenetic, evolutionary and genomic studies. PMID:19199067

  17. Karyotypic analysis and FISH mapping of microsatellite motifs reveal highly differentiated XX/XY sex chromosomes in the pink-tailed worm-lizard (Aprasia parapulchella, Pygopodidae, Squamata)

    PubMed Central

    2013-01-01

    Background The infraorder Gekkota is intriguing because it contains multiple chromosomal and environmental sex determination systems that vary even among closely related taxa. Here, we compare male and females karyotypes of the pink-tailed worm-lizard (Aprasia parapulchella), a small legless lizard belonging to the endemic Australian family Pygopodidae. Results We applied comparative genomic hybridization to reveal an XX/XY sex chromosome system in which the Y chromosome is highly differentiated from the X in both gross morphology and DNA sequence. In addition, FISH mapping has revealed that two microsatellite repeat motifs, (AGAT)n and (AC)n, have been amplified multiple times on the Y chromosome. Conclusion XY karyotypes are found in other pygopodids (Delma inornata and Lialis burtonis), suggesting that the common ancestor of Pygopodidae also had XY sex chromosomes. However, the morphology and size of the Y chromosomes are different among the three species, suggesting that the processes underlying the evolution of sex chromosomes in the Pygopodidae involved chromosome rearrangements and accumulation and amplification of repeats. PMID:24344753

  18. A new species of the genus Eremias Fitzinger, 1834 (Squamata: Lacertidae) from Central Iran, supported by mtDNA sequences and morphology.

    PubMed

    Rastegar-Pouyani, Eskandar; Hosseinian, Saeed; Rafiee, Soolmaz; Kami, Haji Gholi; Rajabizadeh, Mehdi; Wink, Michael

    2016-06-29

    A new species of the lacertid genus Eremias Fitzinger, 1834 is described from northwest of Isfahan province, Central Iran. Two mitochondrial genes (cyt b and 12S DNA) were sequenced and analyzed as reliable molecular markers for the separation of this newly discovered species from closely related species within the genus Eremias: E. velox, E. persica, E. papenfussi, E. lalezharica, E. montana, E. strauchi, E. kopetdaghica and E. suphani. Genetic distances (K2-p) between any of these species with the newly described species are relatively high (27.5-32.8% for cyt b and 5.2-10.4% for 12S DNA). Phylogenetic analyses (MP, ML and BI) generated trees with very similar topologies. According to molecular and morphological data, Eremias isfahanica sp. nov. belongs to the subgenus Aspidorhinus, and is closely related to E. papenfussi. Because several new Eremias species have recently been described from the Iranian Plateau, we additionally provide an updated identification key.

  19. Complete mitochondrial genome of the desert toad-headed agama, Phrynocephalus przewalskii (Reptilia, Squamata, Agamidae), a novel gene organization in vertebrate mtDNA.

    PubMed

    Li, Donghai; Song, Sen; Chen, Tao; Zhang, Caihong; Chang, Cheng

    2015-01-01

    The mitogenome of the desert toad-headed agama, Phrynocephalus przewalskii, was amplified using polymerase chain reaction (PCR), long-and-accurate PCR and directly sequenced by primer walking. The complete mitogenome was 16,892 bp in size and contained 13 protein-coding, 23 tRNA, and 2 rRNA genes, and 1 control region. The mitogenome of the P. przewalskii was similar to those of other Phrynocephalus sand lizards in gene arrangement and composition, except that tRNA-Phe and tRNA-Pro were exchanged and tRNA-Phe had two copies. The control region comprised three parts, one between tRNA-Thr and tRNA-Phe, a second between the two tRNA-Phe copies, and a third between tRNA-Pro and 12S RNA. The overall nucleotide composition of the H-strand was 36.3% A, 26.7% T, 12.5% G, 24.6% C. The complete mitogenome of P. przewalskii will contribute to understanding the evolution of the genus Phrynocephalus and the family Agamidae.

  20. Commentary on the type material of Tantilla gracilis Baird and Girard, 1853 and Tantilla nigriceps Kennicott, 1860 (Reptilia: Squamata), with a neotype designation for T. nigriceps

    USGS Publications Warehouse

    Gotte, S.W.; Wilson, L.D.

    2005-01-01

    We demonstrate that USNM 2040 and not UMMZ 3781 (originally part of lot USNM 4500) was most likely the holotype of Tantilla gracilis. The type specimens of Tantilla nigriceps have been lost or destroyed. It is not possible to determine from the original description of Tantilla nigriceps if this name represents what is currently known as T. nigriceps or T. hobartsmithi. In order to attribute the name T. nigriceps firmly to the species as currently recognized, we designate a neotype.

  1. Pygmy chameleons of the Rhampholeon platyceps compex (Squamata: Chamaeleonidae): description of four new species from isolated 'sky islands' of northern Mozambique.

    PubMed

    Branch, William R; Bayliss, Julian; Tolley, Krystal A

    2014-06-06

    The taxonomic status of recently discovered populations of pygmy chameleons (Rhampholeon) from the northern Mozambique montane isolates of Mt. Chiperone, Mt. Mabu, Mt. Inago and Mt. Namuli are assessed, and compared with the closest geographical congeners, including Rhampholeon platyceps Günther 1893 from Mt. Mulanje, and Rh. chapmanorum Tilbury 1992 from the Malawi Hills, both in southern Malawi. Relationships were examined using morphological features and a phylogenetic analysis incorporating two mitochondrial and one nuclear marker. The phylogeny showed that each montane isolate contained a distinct, well-supported clade of chameleons. Chameleons from the Mozambican montane isolates are within a monophyletic clade inclusive of species from southern Malawi (Rh. platyceps and Rh. chapmanorum). Although some relationships are unresolved, the southern Malawi and Mozambican isolates appear to share their most recent common ancestor with species from the Eastern Arc Mountains and Southern Highlands of Tanzania and Malawi (Rh. moyeri, Rh. uluguruesis, Rh. nchisiensis). Along with Rh. beraduccii and Rh. acuminatus, all are included in the subgenus Rhinodigitum. Sister to this larger clade are species from west/central Africa (Rh. temporalis, Rh. spectrum) and the Rh. marshalli-gorongosae complex from southwest Mozambique and adjacent Zimbabwe. Morphological and molecular results confirm that Brookesia platyceps carri Loveridge 1953 is a junior subjective synonym of Rhampholeon platyceps Günther 1892. Historical records of Rh. platyceps from the Shire Highlands (Chiromo) and the Zomba Plateau, are incorrect and the species is now considered endemic to the Mulanje massif. All of the four newly discovered, isolated populations are genetically and morphologically distinct, and we take the opportunity to describe each as a new species. Rhampholeon (Rhinodigitum) maspictus sp. nov. is restricted to Mt. Mabu and distinguished by its large size, well-developed dorsal crenulations, and bright male breeding coloration; Rhampholeon (Rhinodigitum) nebulauctor sp. nov. is restricted to Mt. Chiperone and distinguished by its small size, weakly-developed dorsal crenulations, and a large rostral process in males; Rhampholeon (Rhinodigitum) tilburyi sp. nov. is restricted to Mt. Namuli and distinguished by its small size, weakly-developed dorsal crenulations, and prominent flexure of the snout in males; and Rhampholeon (Rhinodigitum) bruessoworum sp. nov. is restricted to Mt. Inago and distinguished by its small size, weakly-developed dorsal crenulations, large rostral process in males, and relatively long tail in both sexes. 

  2. Establishing a New Species Encephalitozoon pogonae for the Microsporidian Parasite of Inland Bearded Dragon Pogona vitticeps Ahl 1927 (Reptilia, Squamata, Agamidae).

    PubMed

    Sokolova, Yuliya Y; Sakaguchi, Kanako; Paulsen, Daniel B

    2016-07-01

    The microsporidium parasitizing Inland Bearded Dragons Pogona vitticeps, and developing primarily in macrophages within foci of granulomatous inflammation of different organs, is described as a new species Encephalitozoon pogonae. Establishing the new species was based on sequencing the ITS-SSUrDNA region of the ribosomal gene and consequent SSUrDNA-inferred phylogenetic analyses, as well as on comparison of pathogenesis, host specificity, and ultrastructure among Encephalitozoon species and isolates. The new species is closely related to E. lacertae and E. cuniculi. Analysis of the literature suggests that this microsporidium has been reported previously as an unidentified microsporidian species or isolate of E. cuniculi and may represent a common infection in bearded dragons. All stages of E. pogonae develop in parasitophorous vacuoles. Uninucleate spores on methanol-fixed smears measured 2.1 × 1.1 μm, range 1.7-2.6 × 0.9-1.7 μm; on ultrathin sections spores measured 0.8-1.1 × 1.8-2.2 μm. Ultrastructural study revealed 3-6 polar filament coils, a mushroom-shaped polar disk, and a polar sac embracing half of the volume occupied by the lamellar polaroplast. In activated spores, polar filament everted eccentrically. The overall morphology and intracellular development of E. pogonae were similar to other Encepahalitozoon spp. We also review the existing data on microsporidia infecting reptiles.

  3. Plasma concentrations of progesterone and estradiol and the relation to reproduction in Galápagos land iguanas, Conolophus marthae and C. subcristatus (Squamata, Iguanidae).

    PubMed

    Onorati, Michela; Sancesario, Giulia; Pastore, Donatella; Bernardini, Sergio; Carrión, Jorge E; Carosi, Monica; Vignoli, Leonardo; Lauro, Davide; Gentile, Gabriele

    2016-09-01

    In a combined approach, endocrine and ultrasonic analyses were performed to assess reproduction of two syntopic populations of terrestrial Galápagos iguanas the Conolophus marthae (the Galápagos Pink Land Iguana) and C. subcristatus on the Volcán Wolf (Isabela Island). The ELISA methods (enzyme-linked immunosorbent assay) were used to measure plasma concentrations of progesterone (P4) and 17β-estradiol (E2) from samples collected over the course of three different seasons: July 2010, June 2012-2014. As for C. subcristatus, the large number of females with eggs in 2012 and 2014 were associated with increased plasma P4 concentrations and the corresponding absence of females with eggs in July 2010 when concentrations of both hormones levels were basal indicating reproduction was still ongoing in June and had ended in July. In C. marthae, even though there was a positive relationship between egg-development stages and hormone concentrations, P4 concentrations were basal through the three years that samples were collected, with some females having a lesser number of eggs compared with C. subcristatus. In C. marthae P4 and E2 patterns did not allow for defining a specific breeding season.

  4. Sampling strategies for delimiting species: genes, individuals, and populations in the Liolaemus elongatus-kriegi complex (Squamata: Liolaemidae) in Andean-Patagonian South America.

    PubMed

    Morando, Mariana; Avila, Luciano J; Sites, Jack W

    2003-04-01

    Recovery of evolutionary history and delimiting species boundaries in widely distributed, poorly known groups requires extensive geographic sampling, but sampling regimes are difficult to design a priori because evolutionary diversity is often "hidden" by inadequate taxonomy. Large data sets are needed, and these provide unique challenges for analysis when they span intra- and interspecific levels of divergence. However, protocols have been designed to combine methods of analysis for DNA sequences that exhibit both very shallow and relatively deeper divergences. In this study, we combined several tree-based phylogeny reconstruction methods with nested-clade analysis to extract maximum historical signal at various levels in the poorly known Liolaemus elongatus-kriegi lizard complex in temperate South America. We implemented a recently descrirbed tree-based protocol for DNA sequences to test for species boundaries, and we propose modifications to accommodate large data sets and gene regions with heterogeneous substitution rates. Combining haplotype trees with nested-clade analyses allowed testing of species boundaries on the basis of a priori defined criteria. The results obtained suggest that the number of putative species in the L. elongatus-kriegi complex could be doubled. We discuss these findings in the context of the advantages and limitations of a combined approach for retrieval of maximum historical information in large data sets and with reference to the yet formidable unresolved issues of sampling strategies.

  5. Quaternary range and demographic expansion of Liolaemus darwinii (Squamata: Liolaemidae) in the Monte Desert of Central Argentina using Bayesian phylogeography and ecological niche modelling.

    PubMed

    Camargo, Arley; Werneck, Fernanda P; Morando, Mariana; Sites, Jack W; Avila, Luciano J

    2013-08-01

    Until recently, most phylogeographic approaches have been unable to distinguish between demographic and range expansion processes, making it difficult to test for the possibility of range expansion without population growth and vice versa. In this study, we applied a Bayesian phylogeographic approach to reconstruct both demographic and range expansion in the lizard Liolaemus darwinii of the Monte Desert in Central Argentina, during the Late Quaternary. Based on analysis of 14 anonymous nuclear loci and the cytochrome b mitochondrial DNA gene, we detected signals of demographic expansion starting at ~55 ka based on Bayesian Skyline and Skyride Plots. In contrast, Bayesian relaxed models of spatial diffusion suggested that range expansion occurred only between ~95 and 55 ka, and more recently, diffusion rates were very low during demographic expansion. The possibility of population growth without substantial range expansion could account for the shared patterns of demographic expansion during the Last Glacial Maxima (OIS 2 and 4) in fish, small mammals and other lizards of the Monte Desert. We found substantial variation in diffusion rates over time, and very high rates during the range expansion phase, consistent with a rapidly advancing expansion front towards the southeast shown by palaeo-distribution models. Furthermore, the estimated diffusion rates are congruent with observed dispersal rates of lizards in field conditions and therefore provide additional confidence to the temporal scale of inferred phylogeographic patterns. Our study highlights how the integration of phylogeography with palaeo-distribution models can shed light on both demographic and range expansion processes and their potential causes.

  6. Nuclear markers support the mitochondrial phylogeny of Vipera ursinii-renardi complex (Squamata: Viperidae) and species status for the Greek meadow viper.

    PubMed

    Mizsei, Edvárd; Jablonski, Daniel; Roussos, Stephanos A; Dimaki, Maria; Ioannidis, Yannis; Nilson, Göran; Nagy, Zoltán T

    2017-01-31

    Meadow vipers (Vipera ursinii-renardi complex) are small-bodied snakes that live in either lowland grasslands or montane subalpine-alpine meadows spanning a distribution from France to western China. This complex has previously been the focus of several taxonomic studies which were based mainly on morphological, allozyme or immunological characters and did not clearly resolve the relationships between the various taxa. Recent mitochondrial DNA analyses found unexpected relationships within the complex which had taxonomical consequences for the detected lineages. The most surprising was the basal phylogenetic position of Vipera ursinii graeca, a taxon described almost 30 years ago from the mountains of Greece. We present here new analyses of three nuclear markers (BDNF, NT3, PRLR; a first for studies of meadow and steppe vipers) as well as analyses of newly obtained mitochondrial DNA sequences (CYT B, ND4).Our Bayesian analyses of nuclear sequences are concordant with previous studies of mitochondrial DNA, in that the phylogenetic position of the graeca clade is a clearly distinguished and distinct lineage separated from all other taxa in the complex. These phylogenetic results are also supported by a distinct morphology, ecology and isolated distribution of this unique taxon. Based on several data sets and an integrative species concept we recommend to elevate this taxon to species level: Vipera graeca Nilson & Andrén, 1988 stat. nov.

  7. A ZZ/ZW sex chromosome system in the thick-tailed Gecko ( Underwoodisaurus milii; Squamata: Gekkota: Carphodactylidae), a member of the ancient gecko lineage.

    PubMed

    Pokorná, M; Rens, W; Rovatsos, M; Kratochvíl, L

    2014-01-01

    Geckos (Gekkota) are a highly diversified group of lizards with an exceptional diversity in sex-determining systems. Despite this intriguing documented variability, data on sex determination in many lineages is still scarce. Here, we document the previously overlooked heteromorphic ZZ/ZW sex chromosomes in the thick-tailed gecko, Underwoodisaurus milii, a member of the ancient lineage of pygopodoid geckos. The finding of female heterogamety within pygopodoid geckos was unexpected, as until now only male heterogamety and environmental sex determination have been reported in this group, and female heterogamety was known only in distantly related gecko families separated from the pygopodoid geckos around 150 million years ago. The W chromosome in U. milii is highly heterochromatic and contains a large number of telomeric-like repeats comparable to around 50% of all telomeric-like sequences present in male genomes. The accumulation of these repeats might have been responsible for the considerable size expansion of the W chromosome in comparison to the Z chromosome. The heteromorphic ZZ/ZW sex chromosomes with accumulated telomeric-like repeats in the thick-tailed geckos further illustrate the exceptional diversity of sex-determining systems in geckos and add important information to our understanding of the evolution and phylogeny of sex-determining systems in reptiles.

  8. Cyrtodactylus rosichonariefi sp. nov. (Squamata: Gekkonidae), a new swamp-dwelling bent-toed gecko from Bunguran Island (Great Natuna), Indonesia.

    PubMed

    Riyanto, Awal; Grismer, L Lee; Wood, Perry L

    2015-05-29

    Cyrtodactylus rosichonariefi sp. nov. is the second newly described species of Bent-toed gecko from Bunguran Island (Great Natuna), Indonesia. This species occurs in the Sekunyam Forest and is differentiated from all other species of the C. semenanjungensis species group of the Thai-Malay Peninsula by having the following unique combination of characteristics: intermediate size (SVL of adult male holotype 54.6 mm); enlarged femoral scales, no femoral pores, no precloacal groove, enlarged precloacal scales, no precloacal pores; subcaudals not enlarged; and dorsal pattern blotched but lacking paired, dark, semilunar-shaped blotches on upper nape. The new species is the sister species of C. majulah Grismer, Wood & Lim. [Corrected

  9. Hiding in plain sight: a new species of bent-toed gecko (Squamata: Gekkonidae: Cyrtodactylus) from West Timor, collected by Malcolm Smith in 1924.

    PubMed

    Kathriner, Andrew; Bauer, Aaron M; O'shea, Mark; Sanchez, Caitlin; Kaiser, Hinrich

    2014-12-24

    We describe a new species of bent-toed gecko from a single specimen initially collected in 1924 by Malcolm Smith on Timor Island in the Lesser Sunda Archipelago of Indonesia. Cyrtodactylus celatus sp. nov. is distinguished from all other congeners by the following combination of characters: small adult size; without spinose tubercles on the ventrolateral body fold and along the lateral margin of the tail; 16 longitudinal rows of tubercles at midbody; 42 ventral scales between the ventrolateral folds at midbody; no transversely enlarged, median subcaudal scales; 17 subdigital lamellae (seven basal + ten distal) under the fourth toe; no abrupt transition between postfemoral and ventral femoral scale series. The specimen is the earliest confirmed record of the genus Cyrtodactylus for Timor, and it is the first putatively endemic gecko species described from this island. 

  10. A new species of karst-adapted Cnemaspis Strauch, 1887 (Squamata: Gekkonidae) from a threatened karst region in Pahang, Peninsular Malaysia.

    PubMed

    Grismer, L Lee; Wood, Perry L; Mohamed, Maketab; Chan, Kin Onn; Heinz, Heather M; Sumarli, Alex S-I; Chan, Jacob A; Loredo, Ariel I

    2013-12-12

    A new species of karst-adapted gekkonid lizard of the genus Cnemaspis Strauch is described from Gua Gunting and Gua Goyang in a karst region of Merapoh, Pahang, Peninsular Malaysia whose unique limestone formations are in immediate danger of being quarried. The new species differs from all other species of Cnemaspis based on its unique suite of morphological and color pattern characters. Its discovery underscores the unique biodiversity endemic to karst regions and adds to a growing list of karst-adapted reptiles from Peninsular Malaysia. We posit that new karst-adapted species endemic to limestone forests will continue to be discovered and these regions will harbor a significant percentage of Peninsular Malaysia's biodiversity and thusly should be conserved rather than quarried.

  11. Isolation, characterization, cloning and expression of an alpha-neurotoxin from the venom of the Mexican coral snake Micrurus laticollaris (Squamata: Elapidae).

    PubMed

    Carbajal-Saucedo, Alejandro; López-Vera, Estuardo; Bénard-Valle, Melisa; Smith, Eric N; Zamudio, Fernando; de Roodt, Adolfo R; Olvera-Rodríguez, Alejandro

    2013-05-01

    A new member of short chain α-neurotoxic protein family from venom of the Mexican coral snake, Micrurus laticollaris, was characterized. This protein, named MlatA1, possesses 61 amino acids with 8 conserved cysteine residues, sharing 30-91% sequence identity with other fully sequenced Micrurus toxins. MlatA1 (LD50i.v. = 0.064 mg/kg) antagonizes with both fetal and adult nicotinic acetylcholine receptor (nAChR) as well as α-7 neuronal nAChR in a dose-dependent way. Specific rabbit anti-Mlat serum (titer higher than 18,000) does not show any protective ability against this toxin, nevertheless it was able to recognize protein bands in six out of twelve Micrurus venoms showing the existence of two distinct antigenic groups for α-neurotoxins in North American coral snakes species. The MlatA1 gene was cloned and used to produce recombinant toxin (rMlatA1) that was recognized by rabbit anti-native toxin but was depleted of toxic activity.

  12. Species on the rocks: Systematics and biogeography of the rock-dwelling Ptyodactylus geckos (Squamata: Phyllodactylidae) in North Africa and Arabia.

    PubMed

    Metallinou, Margarita; Červenka, Jan; Crochet, Pierre-André; Kratochvíl, Lukáš; Wilms, Thomas; Geniez, Philippe; Shobrak, Mohammed Y; Brito, José C; Carranza, Salvador

    2015-04-01

    The understanding of the diversity of species in the Palearctic and the processes that have generated it is still weak for large parts of the arid areas of North Africa and Arabia. Reptiles are among their most remarkable representatives, with numerous groups well adapted to the diverse environments. The Ptyodactylus geckos are a strictly rock-dwelling genus with homogeneous morphology distributed across mountain formations and rocky plateaus from the western African ranges in Mauritania and the Maghreb to the eastern tip of the Arabian Peninsula, with an isolated species in southern Pakistan. Here, we use a broad sampling of 378 specimens, two mitochondrial (12S and cytb) and four nuclear (c-mos, MC1R, ACM4, RAG2) markers in order to obtain the first time-calibrated molecular phylogeny of the genus and place its diversification in a temporal framework. The results reveal high levels of intraspecific variability, indicative of undescribed diversity, and they do not support the monophyly of one species (P. ragazzii). Ptyodactylus species are allopatric across most of their range, which may relate to their high preference for the same type of structural habitat. The onset of their diversification is estimated to have occurred in the Late Oligocene, while that of several deep clades in the phylogeny took place during the Late Miocene, a period when an increase in aridification in North Africa and Arabia initiated.

  13. Molecular phylogeny, species limits, and biogeography of the Brazilian endemic lizard genus Enyalius (Squamata: Leiosauridae): an example of the historical relationship between Atlantic Forests and Amazonia.

    PubMed

    Rodrigues, Miguel Trefaut; Bertolotto, Carolina Elena Viña; Amaro, Renata Cecília; Yonenaga-Yassuda, Yatiyo; Freire, Eliza Maria Xavier; Pellegrino, Katia Cristina Machado

    2014-12-01

    The endemic Brazilian Enyalius encompasses a diverse group of forest lizards with most species restricted to the Atlantic Forest (AF). Their taxonomy is problematic due to extensive variation in color pattern and external morphology. We present the first phylogenetic hypothesis for the genus based on 2102 bp of the mtDNA (cyt-b, ND4, and 16S) and nuclear (c-mos) regions, uncovering all previously admitted taxa (9 spp). Different methods of tree reconstruction were explored with Urostrophus vautieri, Anisolepis grilli and A. longicauda as outgroups. The monophyly of Enyalius and its split into two deeply divergent clades (late Oligocene and early Miocene) is strongly supported. Clade A assembles most lineages restricted to south and southeastern Brazil, and within it Enyalius brasiliensis is polyphyletic; herein full species status of E. brasiliensis and E. boulengeri is resurrected. Clade B unites the Amazonian E. leechii as sister-group to a major clade containing E. bilineatus as sister-group to all remaining species from northeastern Brazil. We detected unrecognized diversity in several populations suggesting putative species. Biogeographical analyses indicate that Enyalius keeps fidelity to shadowed forests, with few cases of dispersal into open regions. Ancient dispersal into the Amazon from an AF ancestor may have occurred through northeastern Brazil.

  14. Description and phylogenetic relationships of a new genus and two new species of lizards from Brazilian Amazonia, with nomenclatural comments on the taxonomy of Gymnophthalmidae (Reptilia: Squamata).

    PubMed

    Colli, Guarino R; Hoogmoed, Marinus S; Cannatella, David C; Cassimiro, José; Gomes, Jerriane Oliveira; Ghellere, José Mário; Gomes, Jerriane Oliveira; Ghellere, José Mário; Nunes, Pedro M Sales; Pellegrino, Kátia C M; Salerno, Patricia; Souza, Sergio Marques De; Rodrigues, Miguel Trefaut

    2015-08-18

    We describe a new genus and two new species of gymnophthalmid lizards based on specimens collected from Brazilian Amazonia, mostly in the "arc of deforestation". The new genus is easily distinguished from other Gymnophthalmidae by having very wide, smooth, and imbricate nuchals, arranged in two longitudinal and 6-10 transverse rows from nape to brachium level, followed by much narrower, strongly keeled, lanceolate, and mucronate scales. It also differs from all other Gymnophthalmidae, except Iphisa, by the presence of two longitudinal rows of ventrals. The new genus differs from Iphisa by having two pairs of enlarged chinshields (one in Iphisa); posterior dorsal scales lanceolate, strongly keeled and not arranged in longitudinal rows (dorsals broad, smooth and forming two longitudinal rows), and lateral scales keeled (smooth). Maximum parsimony, maximum likelihood, and Bayesian phylogenetic analyses based on morphological and molecular data indicate the new species form a clade that is most closely related to Iphisa. We also address several nomenclatural issues and present a revised classification of Gymnophthalmidae.

  15. Three new karst-dwelling Cnemaspis Strauch, 1887 (Squamata; Gekkoniade) from Peninsular Thailand and the phylogenetic placement of C. punctatonuchalis and C. vandeventeri.

    PubMed

    Wood, Perry Lee; Grismer, L Lee; Aowphol, Anchalee; Aguilar, César A; Cota, Micheal; Grismer, Marta S; Murdoch, Matthew L; Sites, Jack W

    2017-01-01

    Three new species of Rock Geckos Cnemaspis lineogularis sp. nov., C. phangngaensis sp. nov., and C. thachanaensis sp. nov. of the chanthaburiensis and siamensis groups are described from the Thai portion of the Thai-Malay Peninsula. These new species are distinguished from all other species in their two respective groups based on a unique combination of morphological characteristics, which is further supported by mitochondrial DNA (mtDNA) from the NADH dehydrogenase subunit 2 gene (ND2). Cnemaspis lineogularis sp. nov. is differentiated from all other species in the chanthaburiensis group by having a smaller maximum SVL 38 mm, 13 paravertebral tubercles, enlarged femoral scales, no caudal bands, and a 19.5-23.0% pairwise sequence divergence (ND2). Cnemaspis phangngaensis sp. nov. is differentiated from all other species in the siamensis group by having the unique combination of 10 infralabial scales, four continuous pore-bearing precloacal scales, paravertebral tubercles linearly arranged, lacking tubercles on the lower flanks, having ventrolateral caudal tubercles anteriorly present, caudal tubercles restricted to a single paraveterbral row on each side, a single median row of keeled subcaudals, and a 8.8-25.2% pairwise sequence divergence (ND2). Cnemaspis thachanaensis sp. nov. is distinguished from all other species in the siamensis group by having 10 or 11 supralabial scales 9-11 infralabial scales, paravertebral tubercles linearly arranged, ventrolateral caudal tubercles anteriorly, caudal tubercles restricted to a single paravertebral row on each side, a single median row of keeled subcaudal scales, lacking a single enlarged subcaudal scale row, lacking postcloaclal tubercles in males, the presence of an enlarged submetatarsal scale at the base if the 1st toe, and a 13.4-28.8% pairwise sequence divergence (ND2). The new phylogenetic analyses place C. punctatonuchalis and C. vandeventeri in the siamensis group with C. punctatonuchalis as the sister species to C. huaseesom and C. vandeventeri as the sister species to C. siamensis, corroborating previous hypotheses based on morphology. The discovery of three new karst-dwelling endemics brings the total number of nominal Thai Cnemaspis species to 15 and underscores the need for continued field research in poorly known areas of the Thai-Malay Peninsula, especially those that are threatened and often overlooked as biodiversity hot spots.

  16. Scale Morphology and Micro-Structure of Monitor Lizards (Squamata: Varanidae: Varanus spp.) and their Allies: Implications for Systematics, Ecology, and Conservation.

    PubMed

    Bucklitsch, Yannick; Böhme, Wolfgang; Koch, André

    2016-08-17

    We analysed scale morphology and micro-structure from five different body regions using scanning electron microscopy (SEM) across all nine recognized subgenera of the monitor lizard genus Varanus including 41 different species investigated. As far as we are aware, this qualitative visual technique was applied by us for the first time to most monitor lizard species and probably also to the primary outgroup and sister species Lanthanotus borneensis. A comprehensive list of 20 scalation characters each with up to seven corresponding character states was established and defined for the five body regions sampled. For the phylogenetic approach, parsimony analyses of the resulting morphological data matrix as well as Bremer and bootstrap support calculations were performed with the software TNT. Our results demonstrate that a variety of micro-ornamentations (i.e., ultra- or micro-dermatoglyphics) as seen in various squamate groups is hardly present in monitor lizards. In several species from six out of nine subgenera, however, we found a honeycomb-shaped micro-structure of foveate polygons. Two further samples of Euprepiosaurus Fitzinger, 1843 exhibit each another unique microscopic structure on the scale surface. Notably, the majority of species showing the honeycombed ultra-structure inhabit arid habitats in Australia, Africa and the Middle East. Therefore, it can be inferred that this microscopic scalation feature, which has also been identified in other desert dwelling lizard species, is taxonomically and ecologically correlated with a xeric habitat type in varanids, too. In addition, the systematic affiliation of V. spinulosus, an endemic monitor lizard species from the Solomon Islands with an extraordinary scale shape, is discussed in the light of current hypotheses about its phylogenetic position within the Varanidae. Due to its unique scalation characteristics, in combination with other morphological evidence, a new monotypic subgenus, Solomonsaurus subgen. nov., is erected for this enigmatic monitor lizard species. Furthermore, we propose a taxonomic splitting of the morphologically and ecologically heterogeneous subgenus Euprepiosaurus comprising the Pacific or mangrove and the tree monitor lizards, respectively, again based on the SEM data. Thus, for the members of the highly arboreal V. prasinus species group erection of a new subgenus, Hapturosaurus subgen. nov., is justified based on the autapomorphic scale shape in concert with further morphological, phylogenetic and ecological evidence. In addition, V. reisingeri originally described as a distinct species is considered conspecific with the wide-spread V. prasinus due to joint synapormorphic features in the ventral scale micro-structure. Consequently, V. prasinus is (again) rendered polytypic with the taxon reisingeri being assigned subspecies status here.        In conclusion, the established scalation characters allow discrimination of single species even among closely-related Varanus species, such as the members of the V. indicus species group. Together with a recently published identification key for Southeast Asian monitor lizards based on macroscopic phenotypic characters (Koch et al. 2013), the SEM-pictures of the present study may serve as additional references for the microscopic identification of CITES-relevant monitor lizard skins and products, respectively.

  17. [Demography and nesting ecology of green iguana, Iguana iguana (Squamata: Iguanidae), in 2 exploited populations in Depresión Momposina, Colombia].

    PubMed

    Muñoz, Eliana M; Ortega, Angela M; Bock, Brian C; Páez, Vivian P

    2003-03-01

    We studied the demography and nesting ecology of two populations of Iguana iguana that face heavy exploitation and habitat modification in the Momposina Depression, Colombia. Lineal transect data was analyzed using the Fourier model to provide estimates of social group densities, which was found to differ both within and among populations (1.05-6.0 groups/ha). Mean group size and overall iguana density estimates varied between populations as well (1.5-13.7 iguanas/ha). The density estimates were far lower than those reported from more protected areas in Panama and Venezuela. Iguana densities were consistently higher in sites located along rivers (2.5 iguanas/group) than in sites along the margin of marshes, probably due to vegetational differences (1.5 iguanas/group). There was no correlation between density estimates and estimates of relative abundance (number of iguanas seen/hour/person) due to differing detectabilities of iguana groups among sites. The adult sex ratio (1:2.5 males:females) agreed well with other reports in the literature based upon observation of adult social groups, and probably results from the polygynous mating system in this species rather than a real demographic skew. Nesting in this population occurs from the end of January through March and hatching occurs between April and May. We monitored 34 nests, which suffered little vertebrate predation, perhaps due to the lack of a complete vertebrate fauna in this densely inhabited area, but nests suffered from inundation, cattle trampling, and infestation by phorid fly larvae. Clutch sizes in these populations were lower than all other published reports except for the iguana population on the highly xeric island of Curaçao, implying that adult females in our area are unusually small. We argue that this is more likely the result of the exploitation of these populations rather than an adaptive response to environmentally extreme conditions.

  18. Taxonomic revision of the Australian arid zone lizards Gehyra variegata and G. montium (Squamata, Gekkonidae) with description of three new species.

    PubMed

    Hutchinson, Mark N; Sistrom, Mark J; Donnellan, Stephen C; Hutchinson, Rhonda G

    2014-06-09

    The taxonomy of central Australian populations of geckos of the genus Gehyra has been uncertain since chromosomal studies carried out in the 1970s and 1980s revealed considerable heterogeneity and apparently independent patterns of morphological and karyotypic diversity. Following detailed molecular genetic studies, species boundaries in this complex have become clearer and we here re-set the boundaries of the three named species involved, G. variegata (Duméril & Bibron, 1836), G. montium Storr, 1982, and G. nana King, 1982, and describe three new species. Two of the new species, G. moritzi and G. pulingka, include populations formerly assigned to either G. montium or G. nana Storr, 1982, while the third, G. versicolor, includes all of the eastern Australian populations formerly assigned to G. variegata.

  19. Molecular phylogeny, biogeography and insights into the origin of parthenogenesis in the Neotropical genus Leposoma (Squamata: Gymnophthalmidae): Ancient links between the Atlantic Forest and Amazonia.

    PubMed

    Pellegrino, Katia C M; Rodrigues, Miguel T; Harris, D James; Yonenaga-Yassuda, Yatiyo; Sites, Jack W

    2011-11-01

    Leposoma is a conspicuous component of leaf litter herpetofauna of South and Central American rainforests. The 15 bisexual and one parthenogenetic species are allocated to the parietale and scincoides groups based on morphology. Phylogenetic analyses of 1830 bp (mtDNA+nuclear) were performed on 63 specimens of four species from Amazonian and Panamanian rainforests, and six species and one undescribed form from the Atlantic Forest. Different methods of tree reconstruction were explored, with Anotosaura vanzolinia and Colobosauroides cearensis as outgroups. The monophyly of the parietale and scincoides groups is strongly supported. Contrary to previous hypotheses suggesting a recent contact between Atlantic and Amazon forests, our estimates point to an initial split in Miocene. The position of Leposoma baturitensis, endemic to relictual forests in the semiarid Caatingas northeastern Brazil, and its divergence from the remaining species of the Atlantic Forest, suggests an ancient isolation with no indication of a secondary contact with forests of the eastern coast. Our data do not permit unambiguous assignment of parental species of the unisexual Leposoma percarinatum or the mechanism involved in the origin of parthenogenesis, but revealed two highly divergent diploid and triploid lineages within L. percarinatum, indicating that the unisexuals represent a species complex.

  20. Deep divergence and structure in the Tropical Oceanic Pacific: a multilocus phylogeography of a widespread gekkonid lizard (Squamata: Gekkonidae: Gehyra oceanica)

    USGS Publications Warehouse

    Tonione, Maria A.; Fisher, Robert N.; Zhu, Catherine; Moritz, Craig

    2016-01-01

    Aim The islands of the Tropical Oceanic Pacific (TOP) host both local radiations and widespread, colonizing species. The few phylogeographical analyses of widespread species often point to recent human-aided expansions through the Pacific, suggesting that the communities are recently assembled. Here we apply multilocus data to infer biogeographical history of the gekkonid lizard, Gehyra oceanica, which is widespread, but for which prior analyses suggested a pre-human history and in situ diversification. Location Tropical Oceanic Pacific. Methods We generated a data set including mtDNA and diagnostic SNPs for 173 individuals of G. oceanica spanning Micronesia, Melanesia, and Polynesia. For a subset of these individuals, we also sequenced nuclear loci. From these data, we performed maximum likelihood and Bayesian inference to reveal major clades. We also performed Bayesian clustering analyses and coalescence–based species delimitation tests to infer the number of species in this area. Results We found evidence for six independent evolutionary lineages (candidate species) within G. oceanica that diverged between the Pliocene and the early Pleistocene, with high diversity through northern Melanesia, and pairing of northern Melanesian endemic taxa with widespread lineages across Micronesia and Polynesia. Main conclusions The islands of northern Melanesia not only have unrecognized diversity, but also were the source of independent expansions of lineages through the more remote northern and eastern Pacific. These results highlight the very different evolutionary histories of island faunas on remote archipelagos versus those across Melanesia and point to the need for more intensive studies of fauna within Melanesia if we are to understand the evolution of diversity across the tropical Pacific.

  1. A New Iranian Phrynocephalus (Reptilia: Squamata: Agamidae) from the hottest place on earth and a key to the genus Phrynocephalus in southwestern Asia and Arabia.

    PubMed

    Kamali, Kamran; Anderson, Steven C

    2015-01-06

    A new species of agamid lizard, Phrynocephalus lutensis sp. nov., is described from the Lut Desert in Iran. It is a species adapted to wind-blown sand in this semi-isolated basin. It appears to be most closely similar to P. luteoguttatus and P. euptilopus on the basis of external morphology. A key to the 19 known Phrynocephalus species of southwestern Asia and Arabia is presented for the first time.

  2. Integrating early detection with DNA barcoding: species identification of a non-native monitor lizard (Squamata: Varanidae) carcass in Mississippi, U.S.A.

    USGS Publications Warehouse

    Reed, Robert N.; Hopken, Matthew W.; Steen, David A.; Falk, Bryan G.; Piaggio, Antoinette J.

    2016-01-01

    Early detection of invasive species is critical to increasing the probability of successful management. At the primary stage of an invasion, invasive species are easier to control as the population is likely represented by just a few individuals. Detection of these first few individuals can be challenging, particularly if they are cryptic or otherwise characterized by low detectability. The engagement of members of the public may be critical to early detection as there are far more citizen s on the landscape than trained biologists. However, it can be difficult to assess the credibility of public reporting, especially when a diagnostic digital image or a physical specimen in good condition are lacking. DNA barcoding can be used for verification when morphological identification of a specimen is not possible or uncertain (i.e., degraded or partial specimen). DNA barcoding relies on obtaining a DNA sequence from a relatively small fragment of mitochondrial DNA and comparing it to a database of sequences containing a variety of expertly identified species. He rein we report the successful identification of a degraded specimen of a non-native, potentially invasive reptile species (Varanus niloticus) via DNA barcoding, after discovery and reporting by a member of the public.

  3. The Ixodes (Acari: Ixodidae) of Mexico: Parasite-Host and Host-Parasite Checklists

    DTIC Science & Technology

    2007-08-20

    Clover J.R. (1998) Infestation of the southern alligator lizard (Squamata: Anguidae) by Ixodes pacificus (Acari: Ixodidae) and its susceptibility to Borrelia burgdorferi . Journal of Medical Entomology, 35, 1044–1049.

  4. Unusual horizontal transfer of a long interspersed nuclear element between distant vertebrate classes

    PubMed Central

    Kordis, Dusan; Gubensek, Franc

    1998-01-01

    We have shown previously by Southern blot analysis that Bov-B long interspersed nuclear elements (LINEs) are present in different Viperidae snake species. To address the question as to whether Bov-B LINEs really have been transmitted horizontally between vertebrate classes, the analysis has been extended to a larger number of vertebrate, invertebrate, and plant species. In this paper, the evolutionary origin of Bov-B LINEs is shown unequivocally to be in Squamata. The previously proposed horizontal transfer of Bov-B LINEs in vertebrates has been confirmed by their discontinuous phylogenetic distribution in Squamata (Serpentes and two lizard infra-orders) as well as in Ruminantia, by the high level of nucleotide identity, and by their phylogenetic relationships. The horizontal transfer of Bov-B LINEs from Squamata to the ancestor of Ruminantia is evident from the genetic distances and discontinuous phylogenetic distribution. The ancestor of Colubroidea snakes is a possible donor of Bov-B LINEs to Ruminantia. The timing of horizontal transfer has been estimated from the distribution of Bov-B LINEs in Ruminantia and the fossil data of Ruminantia to be 40–50 My ago. The phylogenetic relationships of Bov-B LINEs from the various Squamata species agrees with that of the species phylogeny, suggesting that Bov-B LINEs have been maintained stably by vertical transmission since the origin of Squamata in the Mesozoic era. PMID:9724768

  5. [Genomic structure and sex determination in squamate reptiles].

    PubMed

    Kichigin, I G; Trifonov, V A

    2013-01-01

    Squamata is the largest reptilian order including snakes and lizards which occupies a key position in phylogeny of amniotes. A variety of sex determination modes in lizards is one of the most interesting parts of the biology of this order. These mechanisms are genomic sex determination (both XY and ZW systems) and temperature-dependent sex determination. Studies of squamata sex chromosomes are pivotal for understanding evolution of other vertebrate sex chromosomes. Unfortunately, this clade has long been neglected by molecular geneticists. In this paper, we describe recent data on molecular cytogenetics and genomics of squamates, evolution of their sex chromosomes and sex determination mechanisms.

  6. Cool Season Paleotemperatures at Tree Line in Taiwan

    NASA Astrophysics Data System (ADS)

    Wright, W. E.; Chan, M.

    2011-12-01

    Taiwan has over 200 mountains whose peaks exceed 3,000 meters in elevation. Despite straddling the Tropic of Cancer, the higher peaks have snow and freezing temperatures every winter. Trees growing above 3,500 meters show clear temperature variation, even producing frost rings. Yet unlike temperate tree-line species, with their warm season temperature signal, trees growing at Taiwan's tree line show sensitivity to cool season temperatures. Juniperus squamata growing above 3,500 meters in central Taiwan have ring width time series that commonly exceed 600 years. Presented are the first dendroclimatological analyses from Taiwanese Juniperus squamata.

  7. Divergence and long-distance overseas dispersals of island populations of the Ryukyu five-lined skink, Plestiodon marginatus (Scincidae: Squamata), in the Ryukyu Archipelago, Japan, as revealed by mitochondrial DNA phylogeography.

    PubMed

    Kurita, Kazuki; Hikida, Tsutomu

    2014-04-01

    We assessed the historical biogeography of the Ryukyu five-lined skink, Plestiodon marginatus, and related species (P. stimpsonii and P. elegans). Our specific aims were to reveal the origin, tim- ing, and route of the colonization to three volcanic islands in the northern Tokara Group of the northern Ryukyus: Kuchinoshima, Nakanoshima, and Suwanosejima. We conducted phylogenetic analyses and divergence time estimation using a partial sequence of the mitochondrial cytochrome b gene for P. marginatus collected from across its whole range (the northern and central Ryukyus), and for P. stimpsonii (from the Yaeyama Group of the southern Ryukyus) and P. elegans (from Taiwan). Our results suggest three major clades (A, B, and C). Clades A and B consist of P. marginatus, excluding the Kuchinoshima population, and Clade C consisted of the Kuchinoshima population, P. stimpsonii, and P. elegans. These clades are estimated to have diverged during the Late Miocene to the Late Pliocene. Among the three examined northern Tokara populations, the Kuchinoshima population was shown to be a sister group of P. stimpsonii. The two other populations from Nakanoshima and Suwanosejima Islands were closely related to P. marginatus from the northern part of the Okinawa Group and that from Kodakarajima Island in the southern Tokara Group, respectively. These populations are estimated to have diverged from their respective related spe cies in various ages of the Early to Late Pleistocene, suggesting that they colonized the islands by independent overseas dispersals of approximately 50-850 km via the Kuroshio Current. Taxonomic implications for P. marginatus are also discussed.

  8. The association of Triatoma maculata (Ericsson 1848) with the gecko Thecadactylus rapicauda (Houttuyn 1782) (Reptilia: Squamata: Gekkonidae): a strategy of domiciliation of the Chagas disease peridomestic vector in Venezuela?

    PubMed Central

    Reyes-Lugo, M; Reyes-Contreras, M; Salvi, I; Gelves, W; Avilán, A; Llavaneras, D; Navarrete, LF; Cordero, G; Sánchez, EE; Rodríguez-Acosta, A

    2011-01-01

    Objective To investigate the bioecological relationship between Chagas disease peridomestic vectors and reptiles as source of feeding. Methods In a three-story building, triatomines were captured by direct search and electric vacuum cleaner search in and outside the building. Then, age structure of the captured Triatoma maculata (T. maculata) were identified and recorded. Reptiles living in sympatric with the triatomines were also searched. Results T. maculata were found living sympatric with geckos (Thecadactylus rapicauda) and they bit residents of the apartment building in study. A total of 1 448 individuals of T. maculata were captured within three days, of which 74.2% (1 074 eggs) were eggs, 21.5% were nymphs at different stages, and 4.3% were adults. Conclusions The association of T. maculata and T. rapicauda is an effective strategy of colonizing dwellings located in the vicinity of the habitat where both species are present; and therefore, could have implications of high importance in the intradomiciliary transmission of Chagas disease. PMID:23569775

  9. The missing leopard lizard: Liolaemus ubaghsi sp. nov., a new species of the leopardinus clade (Reptilia: Squamata: Liolaemidae) from the Andes of the O'Higgins Region in Chile.

    PubMed

    Esquerré, Damien; Troncoso-Palacios, Jaime; Garín, Carlos F; Núnez, Herman

    2014-06-17

    Liolaemus is an extremely species rich genus of iguanid lizards from southern South America. Most of the diversity though is found in the Andes Cordillera, between Argentina and Chile. Here we describe Liolaemus ubaghsi sp. nov., from El Teniente Mine, in the Andean mountains of the O'Higgins Region in Chile. This species presents scalation and pattern traits that belong to the leopardinus clade, a group of viviparous, high altitude lizards that inhabit the mountain ranges surrounding Santiago City. The species of this clade in turn belong to the Andean and Patagonian elongatus-kriegi complex. Liolaemus ubaghsi sp. nov. has been previously recognized as L. leopardinus and L. elongatus, nevertheless we present diagnostic traits that allow us to describe it as a new species. It mainly differs from the rest of the leopardinus clade (L. leopardinus, L. ramonensis, L. valdesianus and L. frassinettii) by having the following unique combination of traits: ochre background coloration, a wide dark occipital stripe, dark flanks, white dots dispersed on the dorsum, absence of leopard-like spots and enlarged infralabial scales. 

  10. An inconspicuous, conspicuous new species of Asian pipesnake, genus Cylindrophis (Reptilia: Squamata: Cylindrophiidae), from the south coast of Jawa Tengah, Java, Indonesia, and an overview of the tangled taxonomic history of C. ruffus (Laurenti, 1768).

    PubMed

    Kieckbusch, Max; Mecke, Sven; Hartmann, Lukas; Ehrmantraut, Lisa; O'shea, Mark; Kaiser, Hinrich

    2016-03-20

    We describe a new species of Cylindrophis currently known only from Grabag, Purworejo Regency, Jawa Tengah Pro-vince (Central Java), Java, Indonesia. Cylindrophis subocularis sp. nov. can be distinguished from all congeners by the presence of a single, eponymous subocular scale between the 3rd and 4th or 4th and 5th supralabial, preventing contact between the 4th or 5th supralabial and the orbit, and by having the prefrontal in narrow contact with or separated from the orbit. We preface our description with a detailed account of the tangled taxonomic history of the similar and putatively wide-ranging species C. ruffus, which leads us to (1) remove the name Scytale scheuchzeri from the synonymy of C. ruffus, (2) list the taxon C. rufa var. javanica as species inquirenda, and (3) synonymize C. mirzae with C. ruffus. We provide additional evidence to confirm that the type locality of C. ruffus is Java. Cylindrophis subocularis sp. nov. is the second species of Asian pipesnake from Java.

  11. A new species of bent-toed gecko, genus Cyrtodactylus Gray, 1827 (Reptilia: Squamata: Gekkonidae), from Jawa Timur Province, Java, Indonesia, with taxonomic remarks on C. fumosus (Müller, 1895).

    PubMed

    Hartmann, Lukas; Mecke, Sven; Kieckbusch, Max; Mader, Felix; Kaiser, Hinrich

    2016-01-26

    A new species of the gekkonid lizard genus Cyrtodactylus Gray, 1827 is described from Klakah, Lumajang Regency, Jawa Timur Province, Java, Indonesia. Cyrtodactylus klakahensis sp. nov. can be distinguished from all other congeners by the presence of (1) a deep precloacal groove in males, (2) three rows of enlarged precloacofemoral scales, of which the third row bears 37-38 pores in males, (3) three or four rows of enlarged scales between the precloacofemoral scale rows and the cloaca, forming distinct chevrons, (4) raised and strongly keeled dorsal tubercles in 15-19 rows at midbody, (5) an indistinct lateral fold, (6) 17-20 subdigital lamellae under the 4th toe, and (7) subcaudal scales which are not transversely enlarged. Cyrtodactylus klakahensis sp. nov. is only the third bent-toed gecko species described from Java, indicating that the diversity of this genus on this island has been neglected in the past. Furthermore, we confirm that C. fumosus (Müller, 1895) is a species that possesses a precloacal groove in males and is most likely restricted to northern Sulawesi. That species is defined by a single female holotype (NMB-REPT 2662). Specimens in museum collections catalogued as C. fumosus from localities elsewhere are misidentified and likely represent undescribed species.

  12. A lost species or the loss of stripes? The case of Contomastix lizards from Cabo Polonio, Uruguay, with observations on C. lacertoides (Duméril & Bibron) and Cnemidophorus grandensis Cope (Squamata, Teiidae).

    PubMed

    Borteiro, Claudio; Kolenc, Francisco; Prigioni, Carlos; Lyra, Mariana L; Baldo, Diego

    2013-01-01

    The main goal of this manuscript is the reevaluation of the taxonomic status of the teiid lizard Contomastix charrua, known only from Cabo Polonio, a small coastal rocky outcrop in southeastern Uruguay. This species was erected on the basis of the presence of a second pair of ceratobranchials and longer cornua in the hyoid bone, in addition to a reduced expression of the pattern of coloration as compared with C. lacertoides. Nevertheless, we found that both species have indistinguishable hyoid morphology, bearing C. lacertoides a noticeable second pair of ceratobranchials. Besides, we realized that the pattern of coloration in this species is more variable than previously considered. As a result of the present work, C. charrua is included in the synonymy of C. lacertoides. In addition, we provide some observations on the holotype of Cnemidophorus grandensis, a junior synonym of C. lacertoides.

  13. Applying n-dimensional hypervolumes for species delimitation: unexpected molecular, morphological, and ecological diversity in the Leaf-Toed Gecko Phyllodactylus reissii Peters, 1862 (Squamata: Phyllodactylidae) from northern Peru.

    PubMed

    Koch, Claudia; Flecks, Morris; Venegas, Pablo J; Bialke, Patrick; Valverde, Sebastian; Rödder, Dennis

    2016-09-02

    An integrative taxonomic approach based on morphology, molecular analyses, and climatic niche modeling was used to uncover cryptic diversity in the phyllodactylid gecko species Phyllodactylus reissii. At least three distinct species could be identified among the examined specimens from southern Ecuador and northern Peru. Phyllodactylus magister, described by Noble (1924) from arid Andean valleys of the Chinchipe and Marañón rivers in the Peruvian Department of Cajamarca and synonymized with P. reissii by Dixon & Huey (1970) is elevated from synonymy and a detailed redescription is provided. A new species of the genus Phyllodactylus from the Andean dry forest of the southern Marañón valley is identified and described herein. Phyllodactylus pachamama sp. nov. is differentiated from other South American congeners on the basis of mtDNA sequence divergence, morphological characters, and differences in the realized climatic niche. At least in Peru, P. reissii seems to primarily inhabit the northern coastal region west of the Andes, while the inter-Andean area along the Río Marañón and its tributaries seems to be inhabited mostly by other species of the genus, which are endemic to this area. The Andean valleys are underestimated in terms of biodiversity and lack thorough investigation and conservation actions.

  14. Lost in the middle of the sea, found in the back of the shelf: A new giant species of Trachylepis (Squamata: Scincidae) from Tinhosa Grande islet, Gulf of Guinea.

    PubMed

    Ceríaco, Luis M P

    2015-06-18

    A new species of Trachylepis is described from Tinhosa Grande islet, São Tomé e Príncipe, Gulf of Guinea. Tinhosa Grande islet is a small (20.5 ha), isolated desert islet used by several bird communities as a nesting place. The new species is distinguished from its congeners by its color pattern, size and lepidosis. Due to its limited geographical distribution the new species appears to be one of the most vulnerable vertebrate species on the planet. In this study we provide a brief discussion on the natural history of the new species, as well as conservation concerns and suggestions.

  15. The Knight and the King: two new species of giant bent-toed gecko (Cyrtodactylus, Gekkonidae, Squamata) from northern New Guinea, with comments on endemism in the North Papuan Mountains

    PubMed Central

    Oliver, Paul M.; Richards, Stephen J.; Mumpuni; Rösler, Herbert

    2016-01-01

    Abstract The diverse biota of New Guinea includes many nominally widespread species that actually comprise multiple deeply divergent lineages with more localised histories of evolution. Here we investigate the systematics of the very large geckos of the Cyrtodactylus novaeguineae complex using molecular and morphological data. These data reveal two widespread and divergent lineages that can be distinguished from each other, and from type material of Cyrtodactylus novaeguineae, by aspects of size, build, coloration and male scalation. On the basis of these differences we describe two new species. Both have wide distributions that overlap extensively in the foothill forests of the North Papuan Mountains, however one is seemingly restricted to hill and lower montane forests on the ranges themselves, while the other is more widespread throughout the surrounding lowlands. The taxon endemic to the North Papuan Mountains is related to an apparently lowland form currently known only from Waigeo and Batanta Island far to the west – hinting at a history on island arcs that accreted to form the North Papuan Mountains. PMID:27006624

  16. A revision of the Mexican Anolis (Reptilia, Squamata, Dactyloidae) from the Pacific versant west of the Isthmus de Tehuantepec in the states of Oaxaca, Guerrero, and Puebla, with the description of six new species .

    PubMed

    Köhler, Gunther; Pérez, Raúl Gómez Trejo; Petersen, Claus Bo P; De La Cruz, Fausto R Méndez

    2014-09-19

    We revise the species of anoles occurring along the Pacific versant of Mexico west of the Isthmus de Tehuantepec in the states of Oaxaca, Guerrero, and Puebla. Based on our analyses of morphological and molecular genetic data, we recognize 21 species, six of which we describe as new (i.e., Anolis carlliebi sp. nov., A. immaculogularis sp. nov., A. nietoi sp. nov., A. sacamecatensis sp. nov., A. stevepoei sp. nov., and A. zapotecorum sp. nov.). Furthermore, we synonymize Anolis forbesi Smith & Van Gelder 1955 with Anolis microlepidotus Davis 1954. Of the recognized species, six have smooth ventral scales (i.e., Anolis dunni, A. gadovii, A. liogaster, A. omiltemanus, A. peucephilus, and A. taylori) and 14 have keeled ventral scales (i.e., A. boulengerianus, A. carlliebi, A. immaculogularis, A. megapholidotus, A. microlepidotus, A. nebuloides, A. nebulosus, A. nietoi, A. quercorum, A. sacamecatensis, A. stevepoei, A. subocularis, A. unilobatus, and A. zapotecorum). In one species, A. macrinii, the ventral scales vary from smooth to weakly keeled. For each species we provide color descriptions in life, color photographs in life, descriptions and illustration of hemipenis morphology (if available), description of external morphology, distribution maps based on the specimensexamined, comments on the conservation status, and natural history notes. Finally, we provide a dichotomous key for the identification of the 21 species of anoles occurring along the Pacific versant of Mexico west of the Isthmus de Tehuantepec in the states of Oaxaca, Guerrero, and Puebla. 

  17. Mixed-Up Sex Chromosomes: Identification of Sex Chromosomes in the X1X1X2X2/X1X2Y System of the Legless Lizards of the Genus Lialis (Squamata: Gekkota: Pygopodidae).

    PubMed

    Rovatsos, Michail; Johnson Pokorná, Martina; Altmanová, Marie; Kratochvíl, Lukáš

    2016-01-01

    Geckos in general show extensive variability in sex determining systems, but only male heterogamety has been demonstrated in the members of their legless family Pygopodidae. In the pioneering study published more than 45 years ago, multiple sex chromosomes of the type X1X1X2X2/X1X2Y were described in Burton's legless lizard (Lialisburtonis) based on conventional cytogenetic techniques. We conducted cytogenetic analyses including comparative genomic hybridization and fluorescence in situ hybridization (FISH) with selected cytogenetic markers in this species and the previously cytogenetically unstudied Papua snake lizard (Lialis jicari) to better understand the nature of these sex chromosomes and their differentiation. Both species possess male heterogamety with an X1X1X2X2/X1X2Y sex chromosome system; however, the Y and one of the X chromosomes are not small chromosomes as previously reported in L. burtonis, but the largest macrochromosomal pair in the karyotype. The Y chromosomes in both species have large heterochromatic blocks with extensive accumulations of GATA and AC microsatellite motifs. FISH with telomeric probe revealed an exclusively terminal position of telomeric sequences in L. jicari (2n = 42 chromosomes in females), but extensive interstitial signals, potentially remnants of chromosomal fusions, in L.burtonis (2n = 34 in females). Our study shows that even largely differentiated and heteromorphic sex chromosomes might be misidentified by conventional cytogenetic analyses and that the application of more sensitive cytogenetic techniques for the identification of sex chromosomes is beneficial even in the classical examples of multiple sex chromosomes.

  18. Chemosensory recognition of the marbled whiptail lizard, Aspidoscelis marmorata (Squamata: Teiidae) to odors of sympatric lizards (Crotophytus collaris, Coleonyx brevis, Eumeces obsoletus and Uta stansburiana) that represent different predation risks.

    PubMed

    Punzo, F

    2008-01-01

    The ability of the whiptail lizard Aspidoscelis marmorata (Teiidae) to detect and discriminate chemical stimuli associated with the integument of a sympatric saurophagous lizard (Crotaphytus collaris) was tested. Females of A. marmorata were presented with cotton swabs containing chemical cues from C. collaris and three species of nonsaurophagous lizards, as well as water and cologne (pungency control), and total number of tongue-flick (TF) recorded. Other responses were assessed including directed TF rate, time from initial presentation of the stimulus to first TF (latency), time spent fleeing from the stimulus, and number of flight bouts. The number of TFs, directed TF rate, and number of attempts at fleeing exhibited by were significantly greater when females were presented with swabs containing cues from C. collaris as compared to nonsaurophagous lizards and both control treatments. A. marmorata required significantly less time to elicit their first TF when presented with cues from C. collaris as compared to all other treatments. Most previous studies have focused on the responses of lizards to cues associated with snake predators. This study provides the first available data on responses of a teiid to cues associated with a saurophagous lizard.

  19. The transfer of two clades of Malaysian Sphenomorphus Fitzinger (Squamata: Scincidae) into the genus Tytthoscincus Linkem, Diesmos, & Brown and the description of a new Malaysian swamp-dwelling species.

    PubMed

    Grismer, L Lee; Muin, Mohd Abdul; Wood, Perry L Jr; Anuar, Shahrul; Linkem, Charles W

    2016-03-15

    Phylogenetic analyses based on the mitochondrial gene ND2 and its flanking tRNAs indicate the diminutive upland and insular species Sphenomorphus bukitensis, S. butleri, S. langkawiensis, S. perhentianensis, and S. temengorensis form a monophyletic group that is phylogenetically embedded within the Southeast Asian genus Tytthoscincus. The analyses also indicate that a new swamp-dwelling skink from the Bukit Panchor State Park, Pulau Pinang, Peninsular Malaysia is the sister species to the swamp-dwelling species S. sibuensis from Pulau Sibu, Johor and Singapore and that these two are also embedded in the genus Tytthoscincus. By transferring the two Peninsular Malaysian clades of Sphenomorphus into the genus Tytthoscincus, the monophyly of the latter is maintained. The new species T. panchorensis sp. nov. can be distinguished from all other species of Tytthoscincus by having a unique combination of morphological and color pattern characteristics.

  20. Sesamoid bones in tuatara (Sphenodon punctatus) investigated with X-ray microtomography, and implications for sesamoid evolution in Lepidosauria.

    PubMed

    Regnault, Sophie; Hutchinson, John R; Jones, Marc E H

    2017-01-01

    Sesamoids bones are small intra-tendinous (or ligamentous) ossifications found near joints and are often variable between individuals. Related bones, lunulae, are found within the menisci of certain joints. Several studies have described sesamoids and lunulae in lizards and their close relatives (Squamata) as potentially useful characters in phylogenetic analysis, but their status in the extant outgroup to Squamata, tuatara (Sphenodon), remains unclear. Sphenodon is the only living rhynchocephalian, but museum specimens are valuable and difficult to replace. Here, we use non-destructive X-ray microtomography to investigate the distribution of sesamoids and lunulae in 19 Sphenodon specimens and trace the evolution of these bones in Lepidosauria (Rhynchocephalia + Squamata). We find adult Sphenodon to possess a sesamoid and lunula complement different from any known squamate, but also some variation within Sphenodon specimens. The penultimate phalangeal sesamoids and tibial lunula appear to mineralize prior to skeletal maturity, followed by mineralization of a sesamoid between metatarsal I and the astragalocalcaneum (MTI-AC), the palmar sesamoids, and tibiofemoral lunulae around attainment of skeletal maturity. The tibial patella, ulnar, and plantar sesamoids mineralize late in maturity or variably. Ancestral state reconstruction indicates that the ulnar patella and tibiofemoral lunulae are synapomophies of Squamata, and the palmar sesamoid, tibial patella, tibial lunula, and MTI-AC may be synapomorphies of Lepidosauria. J. Morphol. 278:62-72, 2017. ©© 2016 Wiley Periodicals,Inc.

  1. Effect of beta-adrenergic antagonists on bioluminescence control in three species of brittlestars (Echinodermata: Ophiuroidea).

    PubMed

    Dupont, S; Mallefet, J; Vanderlinden, C

    2004-05-01

    The role of adrenaline in the nervous control of bioluminescence in three brittlestar species, Amphiura filiformis, Amphipholis squamata, and Ophiopsila aranea, was assessed by testing two different beta-adrenergic antagonists (propranolol and labetalol) over a wide concentration range (10(-10)-10(-3)M). We compared the effects of analogues (active vs. inactive) of the same substance (L- and D-enantiomers of propranolol). Propranolol presented both specific and nonspecific effects: (i) nonspecific effects were observed at the higher concentrations tested (10(-4) and 10(-3)M) in all three species; (ii) specific effects were detected only at the lower concentrations tested (10(-6)-10(-5)M). In A. squamata, the involvement of adrenaline in the nervous control of luminescence is supported by propranolol and labetolol specific inhibition. The neuropharmacological implications of nonspecific effects, the involvement of adrenaline and the interspecific differences in the brittlestar nervous control of bioluminescence are discussed.

  2. Antifungal and insecticidal activity of two Juniperus essential oils.

    PubMed

    Wedge, David E; Tabanca, Nurhayat; Sampson, Blair J; Werle, Christopher; Demirci, Betul; Baser, K Husnu Can; Nan, Peng; Duan, Jia; Liu, Zhijun

    2009-01-01

    Essential oils of two Tibetan Junipers Juniperus saltuaria and J. squamata var. fargesii (Cupressaceae) were obtained by distilling dried leaves and branches using a Clevenger apparatus. Sixty-seven compounds from J. saltuaria and 58 from J. squamata var. fargesii were identified by gas chromatography-mass spectrometry (GC-MS). Both essential oils contained similar ratios of four abundant monoterpenoids: 44 and 35% sabinene, 13 and 9% elemol, 8 and 7% terpinen-4-ol, and 4 and 17% alpha-pinene, respectively. These oils had antifungal activity based on a direct bioautography assay of Colletotrichum acutatum, C. fragariae, and C. gloeosporioides, and insecticidal activity based on serial-time mortality bioassay of azalea lace bugs, Stephanitis pyrioides. Antifungal activity of Juniperus oils was weak when compared with commercial fungicides such as benomyl and captan. Whole Juniperus oils at quarter the dosage used against Colletotrichum species were more insecticidal than 10 mg/mL malathion, killing > or =70-90% adult lace bugs after 4 hours of exposure. Rf values of 0.18 for J. saltuaria oil and 0.19 for J. squamata oil indicated lipophilic monoterpenes which were the putative sources of biological activity.

  3. The Evolutionary Implications of Hemipenial Morphology of Rattlesnake Crotalus durissus terrificus (Laurent, 1768) (Serpentes: Viperidae: Crotalinae)

    PubMed Central

    Porto, Marcovan; de Oliveira, Marco Antonio; Pissinatti, Lorenzo; Rodrigues, Renata Lopes; Rojas-Moscoso, Julio Alejandro; Cogo, José Carlos; Metze, Konradin; Antunes, Edson; Nahoum, César; Mónica, Fabíola Z.; De Nucci, Gilberto

    2013-01-01

    Most amniotes vertebrates have an intromittent organ to deliver semen. The reptile Sphenodon and most birds lost the ancestral penis and developed a cloaca-cloaca mating. Known as hemipenises, the copulatory organ of Squamata shows unique features between the amniotes intromittent organ. They are the only paired intromittent organs across amniotes and are fully inverted and encapsulated in the tail when not in use. The histology and ultrastructure of the hemipenes of Crotalus durissus rattlesnake is described as the evolutionary implications of the main features discussed. The organization of hemipenis of Crotalus durissus terrificus in two concentric corpora cavernosa is similar to other Squamata but differ markedly from the organization of the penis found in crocodilians, testudinata, birds and mammals. Based on the available data, the penis of the ancestral amniotes was made of connective tissue and the incorporation of smooth muscle in the framework of the sinusoids occurred independently in mammals and Crotalus durissus. The propulsor action of the muscle retractor penis basalis was confirmed and therefore the named should be changed to musculus hemipenis propulsor.The retractor penis magnus found in Squamata has no homology to the retractor penis of mammals, although both are responsible for the retraction of the copulatory organ. PMID:23840551

  4. The Evolutionary Implications of Hemipenial Morphology of Rattlesnake Crotalus durissus terrificus (Laurent, 1768) (Serpentes: Viperidae: Crotalinae).

    PubMed

    Porto, Marcovan; de Oliveira, Marco Antonio; Pissinatti, Lorenzo; Rodrigues, Renata Lopes; Rojas-Moscoso, Julio Alejandro; Cogo, José Carlos; Metze, Konradin; Antunes, Edson; Nahoum, César; Mónica, Fabíola Z; De Nucci, Gilberto

    2013-01-01

    Most amniotes vertebrates have an intromittent organ to deliver semen. The reptile Sphenodon and most birds lost the ancestral penis and developed a cloaca-cloaca mating. Known as hemipenises, the copulatory organ of Squamata shows unique features between the amniotes intromittent organ. They are the only paired intromittent organs across amniotes and are fully inverted and encapsulated in the tail when not in use. The histology and ultrastructure of the hemipenes of Crotalus durissus rattlesnake is described as the evolutionary implications of the main features discussed. The organization of hemipenis of Crotalus durissus terrificus in two concentric corpora cavernosa is similar to other Squamata but differ markedly from the organization of the penis found in crocodilians, testudinata, birds and mammals. Based on the available data, the penis of the ancestral amniotes was made of connective tissue and the incorporation of smooth muscle in the framework of the sinusoids occurred independently in mammals and Crotalus durissus. The propulsor action of the muscle retractor penis basalis was confirmed and therefore the named should be changed to musculus hemipenis propulsor.The retractor penis magnus found in Squamata has no homology to the retractor penis of mammals, although both are responsible for the retraction of the copulatory organ.

  5. First report of the male of Amblyomma rotundatum (Acari: Ixodidae) from a field-collected host.

    PubMed

    Labruna, Marcelo B; Terrassini, Flávio A; Camargo, Luís Marcelo A

    2005-11-01

    An adult male of the tick Amblyomma rotundatum Koch was collected on a naturally infested lizard, Tropidurus sp. (Squamata: Tropiduridae), at Monte Negro, State of Rondonia, Brazil. The tick's identity was confirmed morphologically and by analysis of the second internal transcribed spacer of the ribosomal DNA. This is the third known male specimen of A. rotundatum, a species that has been shown to reproduce exclusively by parthenogenesis. The two previously reported male specimens seemed to be partially teratological or gynandromorphic, whereas the present specimen shows no visible genetic or developmental anomaly.

  6. Acetylcholine receptors at neuromuscular synapses: phylogenetic differences detected by snake alpha-neurotoxins.

    PubMed Central

    Burden, S J; Hartzell, H C; Yoshikami, D

    1975-01-01

    Phylogenetic differences in acetylcholine receptors from skeletal neuromuscular synapses of various species of snakes and lizards have been investigated, using the snake venom alpha-neurotoxins alpha-atratoxin (cobrotoxin) and alpha-bungarotoxin. The acetylcholine receptors of the phylogenetically primitive lizards, like those from all other vertebrates previously tested, are blocked by these alpha-neurotoxins. In contrast, receptors from snakes and advanced lizards are insensitive to one or both of the toxins. It is suggested that toxin-resistant acetylcholine receptors appeared early in the evolution of Squamata and preceded the appearance of alpha-neurotoxins. Images PMID:1081230

  7. Integration of molecules and new fossils supports a Triassic origin for Lepidosauria (lizards, snakes, and tuatara)

    PubMed Central

    2013-01-01

    Background Lepidosauria (lizards, snakes, tuatara) is a globally distributed and ecologically important group of over 9,000 reptile species. The earliest fossil records are currently restricted to the Late Triassic and often dated to 227 million years ago (Mya). As these early records include taxa that are relatively derived in their morphology (e.g. Brachyrhinodon), an earlier unknown history of Lepidosauria is implied. However, molecular age estimates for Lepidosauria have been problematic; dates for the most recent common ancestor of all lepidosaurs range between approximately 226 and 289 Mya whereas estimates for crown-group Squamata (lizards and snakes) vary more dramatically: 179 to 294 Mya. This uncertainty restricts inferences regarding the patterns of diversification and evolution of Lepidosauria as a whole. Results Here we report on a rhynchocephalian fossil from the Middle Triassic of Germany (Vellberg) that represents the oldest known record of a lepidosaur from anywhere in the world. Reliably dated to 238–240 Mya, this material is about 12 million years older than previously known lepidosaur records and is older than some but not all molecular clock estimates for the origin of lepidosaurs. Using RAG1 sequence data from 76 extant taxa and the new fossil specimens two of several calibrations, we estimate that the most recent common ancestor of Lepidosauria lived at least 242 Mya (238–249.5), and crown-group Squamata originated around 193 Mya (176–213). Conclusion A Early/Middle Triassic date for the origin of Lepidosauria disagrees with previous estimates deep within the Permian and suggests the group evolved as part of the faunal recovery after the end-Permain mass extinction as the climate became more humid. Our origin time for crown-group Squamata coincides with shifts towards warmer climates and dramatic changes in fauna and flora. Most major subclades within Squamata originated in the Cretaceous postdating major continental fragmentation. The

  8. Amblyomma dissimile Koch (Acari: Ixodidae) attacking Primolius maracana Vieillot (Psittaciformes: Psittacidae) in the Amazon region, State of Pará, Brazil.

    PubMed

    Scofield, A; Bahia, M; Martins, A L; Góes-Cavalcante, G; Martins, T F; Labruna, M B

    2011-01-01

    The tick Amblyomma dissimile Koch feeds preferentially on reptiles (Squamata), although amphibians (Anura) also seem to be important hosts. We report an A. dissimile nymph infesting a blue-winged macaw, Primolius maracana, held in captivity in the Mangal das Garças Park, State of Pará, Brazil. Environmental observations suggest that free-living iguanas (Iguana iguana), which used to walk on the bird enclosure in the park, were the source of the A. dissimile tick that infested the blue-winged macaw. We provide the second world record of a bird host for A. dissimile, and the first bird record for this species in South America.

  9. Complete mitochondrial genome of the red-spotted tokay gecko (Gekko gecko, Reptilia: Gekkonidae): comparison of red- and black-spotted tokay geckos.

    PubMed

    Qin, Xin-Min; Qian, Fang; Zeng, De-Long; Liu, Xiao-Can; Li, Hui-Min

    2011-10-01

    Here, we sequenced the complete mitochondrial genome of the red-spotted tokay gecko (Squamata: Gekkonidae). The genome is 16,590 bp in size. Its gene arrangement pattern was identical with that of black-spotted tokay gecko. We compared the mitochondrial genome of red-spotted tokay gecko with that of the black-spotted tokay gecko. Nucleotide sequence of the two whole mitochondrial genomes was 97.99% similar, and the relatively high similarity seems to indicate that they may be separated at the subspecies level. The information of mitochondrial genome comparison of the two morphological types of tokay gecko is discussed in detail.

  10. Eocene lizard from Germany reveals amphisbaenian origins.

    PubMed

    Müller, Johannes; Hipsley, Christy A; Head, Jason J; Kardjilov, Nikolay; Hilger, André; Wuttke, Michael; Reisz, Robert R

    2011-05-19

    Amphisbaenia is a speciose clade of fossorial lizards characterized by a snake-like body and a strongly reinforced skull adapted for head-first burrowing. The evolutionary origins of amphisbaenians are controversial, with molecular data uniting them with lacertids, a clade of Old World terrestrial lizards, whereas morphology supports a grouping with snakes and other limbless squamates. Reports of fossil stem amphisbaenians have been falsified, and no fossils have previously tested these competing phylogenetic hypotheses or shed light on ancestral amphisbaenian ecology. Here we report the discovery of a new lacertid-like lizard from the Eocene Messel locality of Germany that provides the first morphological evidence for lacertid-amphisbaenian monophyly on the basis of a reinforced, akinetic skull roof and braincase, supporting the view that body elongation and limblessness in amphisbaenians and snakes evolved independently. Morphometric analysis of body shape and ecology in squamates indicates that the postcranial anatomy of the new taxon is most consistent with opportunistically burrowing habits, which in combination with cranial reinforcement indicates that head-first burrowing evolved before body elongation and may have been a crucial first step in the evolution of amphisbaenian fossoriality.

  11. Molecular evolution of HoxA13 and the multiple origins of limbless morphologies in amphibians and reptiles.

    PubMed

    Singarete, Marina E; Grizante, Mariana B; Milograna, Sarah R; Nery, Mariana F; Kin, Koryu; Wagner, Günter P; Kohlsdorf, Tiana

    2015-01-01

    Developmental processes and their results, morphological characters, are inherited through transmission of genes regulating development. While there is ample evidence that cis-regulatory elements tend to be modular, with sequence segments dedicated to different roles, the situation for proteins is less clear, being particularly complex for transcription factors with multiple functions. Some motifs mediating protein-protein interactions may be exclusive to particular developmental roles, but it is also possible that motifs are mostly shared among different processes. Here we focus on HoxA13, a protein essential for limb development. We asked whether the HoxA13 amino acid sequence evolved similarly in three limbless clades: Gymnophiona, Amphisbaenia and Serpentes. We explored variation in ω (dN/dS) using a maximum-likelihood framework and HoxA13sequences from 47 species. Comparisons of evolutionary models provided low ω global values and no evidence that HoxA13 experienced relaxed selection in limbless clades. Branch-site models failed to detect evidence for positive selection acting on any site along branches of Amphisbaena and Gymnophiona, while three sites were identified in Serpentes. Examination of alignments did not reveal consistent sequence differences between limbed and limbless species. We conclude that HoxA13 has no modules exclusive to limb development, which may be explained by its involvement in multiple developmental processes.

  12. An Amphisbaenian Skull from the European Miocene and the Evolution of Mediterranean Worm Lizards

    PubMed Central

    Bolet, Arnau; Delfino, Massimo; Fortuny, Josep; Almécija, Sergio; Robles, Josep M.; Alba, David M.

    2014-01-01

    The evolution of blanid amphisbaenians (Mediterranean worm lizards) is mainly inferred based on molecular studies, despite their fossils are common in Cenozoic European localities. This is because the fossil record exclusively consists in isolated elements of limited taxonomic value. We describe the only known fossil amphisbaenian skull from Europe – attributed to Blanus mendezi sp. nov. (Amphisbaenia, Blanidae) – which represents the most informative fossil blanid material ever described. This specimen, from the Middle Miocene of Abocador de Can Mata (11.6 Ma, MN7+8) in the Vallès-Penedès Basin (Catalonia, NE Iberian Peninsula), unambiguously asserts the presence of Blanus in the Miocene of Europe. This reinforces the referral to this genus of the previously-known, much more incomplete and poorly-diagnostic material from other localities of the European Neogene. Our analysis – integrating the available molecular, paleontological and biogeographic data – suggests that the new species postdates the divergence between the two main (Eastern and Western Mediterranean) extant clades of blanids, and probably precedes the split between the Iberian and North-Western African subclades. This supports previous paleobiogeographic scenarios for blanid evolution and provides a significant minimum divergence time for calibrating molecular analyses of blanid phylogeny. PMID:24896828

  13. Ultrastructural differentiation of sperm tail region in Diplometopon zarudnyi (an amphisbaenian reptile)

    PubMed Central

    Al-Dokhi, O.; Mukhtar, Ahmed; Al-Dosary, A.; Al-Sadoon, M.K.

    2015-01-01

    Diplometopon zarudnyi, a worm lizard belongs to amphisbaenia under trogonophidae family. This species exists in limited areas of the Arabian Peninsula and is an oscillating digger found in sub-surface soils. The present study aimed to investigate the sperm tail differentiation in D. zarudnyi. Ten male adults of D. zarudnyi were collected from Riyadh during April–May 2011. To study the sperm tail at the ultrastructural level the testes were fixed in 3% glutaraldehyde, than post fixed in 1% osmium tetaroxide followed by dehydration in ethanol grades; samples were cleared in propylene oxide and embedded in resin. Tail formation begins by the moving of centrioles and mitochondria towards the posterior pole of sperm head. Simultaneously many microtubules of the midpiece axoneme were enclosed by a thick layer of granular material. Mitochondria of midpiece lie alongside the proximal centriole which forms a very short neck region and possess tubular cristae internally and concentric layers of cristae superficially. During this course a fibrous sheath surrounds the axoneme of mid and principal piece. At the end dissolution of longitudinal manchette takes place. The mitochondria then rearrange themselves around the proximal and distal centrioles to form a neck region. Later, the fibrous sheath surrounds the proximal portion of the flagella. This part along with sperm head of D. zarudnyi provides a classical model that could be used in future for evolutionary and phylogenetic purposes of class reptilia. PMID:26155090

  14. Molecular evolution of HoxA13 and the multiple origins of limbless morphologies in amphibians and reptiles

    PubMed Central

    Singarete, Marina E.; Grizante, Mariana B.; Milograna, Sarah R.; Nery, Mariana F.; Kin, Koryu; Wagner, Günter P.; Kohlsdorf, Tiana

    2015-01-01

    Developmental processes and their results, morphological characters, are inherited through transmission of genes regulating development. While there is ample evidence that cis-regulatory elements tend to be modular, with sequence segments dedicated to different roles, the situation for proteins is less clear, being particularly complex for transcription factors with multiple functions. Some motifs mediating protein-protein interactions may be exclusive to particular developmental roles, but it is also possible that motifs are mostly shared among different processes. Here we focus on HoxA13, a protein essential for limb development. We asked whether the HoxA13 amino acid sequence evolved similarly in three limbless clades: Gymnophiona, Amphisbaenia and Serpentes. We explored variation in ω (dN/dS) using a maximum-likelihood framework and HoxA13sequences from 47 species. Comparisons of evolutionary models provided low ω global values and no evidence that HoxA13 experienced relaxed selection in limbless clades. Branch-site models failed to detect evidence for positive selection acting on any site along branches of Amphisbaena and Gymnophiona, while three sites were identified in Serpentes. Examination of alignments did not reveal consistent sequence differences between limbed and limbless species. We conclude that HoxA13 has no modules exclusive to limb development, which may be explained by its involvement in multiple developmental processes. PMID:26500429

  15. A gravid lizard from the Cretaceous of China and the early history of squamate viviparity

    NASA Astrophysics Data System (ADS)

    Wang, Yuan; Evans, Susan E.

    2011-09-01

    Although viviparity is most often associated with mammals, roughly one fifth of extant squamate reptiles give birth to live young. Phylogenetic analyses indicate that the trait evolved more than 100 times within Squamata, a frequency greater than that of all other vertebrate clades combined. However, there is debate as to the antiquity of the trait and, until now, the only direct fossil evidence of squamate viviparity was in Late Cretaceous mosasauroids, specialised marine lizards without modern equivalents. Here, we document viviparity in a specimen of a more generalised lizard, Yabeinosaurus, from the Early Cretaceous of China. The gravid female contains more than 15 young at a level of skeletal development corresponding to that of late embryos of living viviparous lizards. This specimen documents the first occurrence of viviparity in a fossil reptile that was largely terrestrial in life, and extends the temporal distribution of the trait in squamates by at least 30 Ma. As Yabeinosaurus occupies a relatively basal position within crown-group squamates, it suggests that the anatomical and physiological preconditions for viviparity arose early within Squamata.

  16. Macrobenthos of sandy beach and nearshore environments at Murrells Inlet, South Carolina, U.S.A.

    NASA Astrophysics Data System (ADS)

    Knott, David M.; Calder, Dale R.; Van Dolah, Robert F.

    1983-05-01

    Quantitative samples of benthic macrofauna were collected seasonally from sandy beaches and adjacent nearshore areas bordering the entrance of a high salinity inlet in South Carolina. Intertidal stations were numerically dominated by the polychaete Scolelepis squamata, the amphipod Neohaustorius schmitzi and the bivalve Donax variabilis. Abundant subtidal species included the polychaetes Spiophanes bombyx and Scolelepis squamata, the amphipods Protohaustorius deichmannae and Acanthohaustorius millsi, and the bivalve Tellina sp. Species composition, faunal density and species diversity varied along three transects extending from mean high water to depths of about 5 m. Although some species groups were habitat-restricted, the numerically dominant species were widely distributed throughout the subtidal and intertidal zones. Polychaetes dominated the fauna of subtidal and intertidal habitats, both in terms of numbers of species and numbers of individuals. This dominance was attributed to the moderate wave energy in this area, as well as to the sheltering effect of a jetty that was constructed during the course of the study. Jetty construction also resulted in faunal enrichment at intertidal stations on a sheltered transect.

  17. A new hypothesis of squamate evolutionary relationships from nuclear and mitochondrial DNA sequence data

    SciTech Connect

    Townsend, Ted M.; Larson, Allan; Louis, Edward; Macey, J. Robert

    2004-05-19

    Squamate reptiles serve as model systems for evolutionary studies of a variety of morphological and behavioral traits, and phylogeny is crucial to many generalizations derived from such studies. Specifically, the traditional dichotomy between Iguania and Scleroglossa has been correlated with major evolutionary shifts within Squamata. We present a molecular phylogenetic study of squamates using DNA sequence data from the nuclear genes RAG-1 and c-mos and the mitochondrial ND2 region, sampling all major clades and most major subclades. Monophyly of Iguania, Anguimorpha, and almost all currently recognized squamate families is strongly supported. However, monophyly is rejected for Scleroglossa, Varanoidea, and several other higher taxa, and Iguania is highly nested within Squamata. Limblessness evolved independently in snakes, dibamids, and amphisbaenians, suggesting widespread morphological convergence or parallelism in limbless, burrowing forms. Amphisbaenians are the sister group of lacertids, and snakes are grouped with iguanians and anguimorphs. Dibamids diverged early in squamate evolutionary history. Xantusiidae is the sister taxon of Cordylidae. Studies of functional tongue morphology and feeding mode have found significant differences between Scleroglossa and Iguania, and our finding of a nonmonophyletic Scleroglossa and a highly nested Iguania suggest that similar states evolved separately in Sphenodon and Iguania, and that jaw prehension is the ancestral feeding mode in squamates.

  18. Does beach nourishment have long-term effects on intertidal macroinvertebrate species abundance?

    NASA Astrophysics Data System (ADS)

    Leewis, Lies; van Bodegom, Peter M.; Rozema, Jelte; Janssen, Gerard M.

    2012-11-01

    Coastal squeeze is the largest threat for sandy coastal areas. To mitigate seaward threats, erosion and sea level rise, sand nourishment is commonly applied. However, its long-term consequences for macroinvertebrate fauna, critical to most ecosystem services of sandy coasts, are still unknown. Seventeen sandy beaches - nourished and controls - were sampled along a chronosequence to investigate the abundance of four dominant macrofauna species and their relations with nourishment year and relevant coastal environmental variables. Dean's parameter and latitude significantly explained the abundance of the spionid polychaete Scolelepis squamata, Beach Index (BI), sand skewness, beach slope and latitude explained the abundance of the amphipod Haustorius arenarius and Relative Tide Range (RTR), recreation and sand sorting explained the abundance of Bathyporeia sarsi. For Eurydice pulchra, no environmental variable explained its abundance. For H. arenarius, E. pulchra and B. sarsi, there was no relation with nourishment year, indicating that recovery took place within a year after nourishment. Scolelepis squamata initially profited from the nourishment with "over-recolonisation". This confirms its role as an opportunistic species, thereby altering the initial community structure on a beach after nourishment. We conclude that the responses of the four dominant invertebrates studied in the years following beach nourishment are species specific. This shows the importance of knowing the autecology of the sandy beach macroinvertebrate fauna in order to be able to mitigate the effects of beach nourishment and other environmental impacts.

  19. Conservation of chromosomes syntenic with avian autosomes in squamate reptiles revealed by comparative chromosome painting.

    PubMed

    Pokorná, Martina; Giovannotti, Massimo; Kratochvíl, Lukáš; Caputo, Vincenzo; Olmo, Ettore; Ferguson-Smith, Malcolm A; Rens, Willem

    2012-08-01

    In contrast to mammals, birds exhibit a slow rate of chromosomal evolution. It is not clear whether high chromosome conservation is an evolutionary novelty of birds or was inherited from an earlier avian ancestor. The evolutionary conservatism of macrochromosomes between birds and turtles supports the latter possibility; however, the rate of chromosomal evolution is largely unknown in other sauropsids. In squamates, we previously reported strong conservatism of the chromosomes syntenic with the avian Z, which could reflect a peculiarity of this part of the genome. The chromosome 1 of iguanians and snakes is largely syntenic with chromosomes 3, 5 and 7 of the avian ancestral karyotype. In this project, we used comparative chromosome painting to determine how widely this synteny is conserved across nine families covering most of the main lineages of Squamata. The results suggest that the association of the avian ancestral chromosomes 3, 5 and 7 can be dated back to at least the early Jurassic and could be an ancestral characteristic for Unidentata (Serpentes, Iguania, Anguimorpha, Laterata and Scinciformata). In Squamata chromosome conservatism therefore also holds for the parts of the genome which are homologous to bird autosomes, and following on from this, a slow rate of chromosomal evolution could be a common characteristic of all sauropsids. The large evolutionary stasis in chromosome organization in birds therefore seems to be inherited from their ancestors, and it is particularly striking in comparison with mammals, probably the only major tetrapod lineage with an increased rate of chromosomal rearrangements as a whole.

  20. A review of Chilean chiggers (Acari: Trombiculidae), with the description of a new genus and ten new species.

    PubMed

    Stekolnikov, Alexandr A; González-Acuña, Daniel

    2015-05-29

    A new genus and species of chigger mites, Diaguitacarus choapensis gen. et sp. nov., is described from four lizard species of the genus Liolaemus in Choapa Province of Chile. Eight new chigger species are described from lizards of the genera Liolaemus, Phymaturus (Squamata: Liolaemidae), and Microlophus (Squamata: Tropiduridae), in Arica and Parinacota, Atacama, Coquimbo, Valparaíso, and Biobío Regions: Eutrombicula nerudai sp. nov., Eutrombicula mistrali sp. nov., Eutrombicula picunche sp. nov., Microtrombicula mapuche sp. nov., Parasecia molini sp. nov., Paratrombicula philippii sp. nov., Morelacarus jorgei sp. nov., and Morelacarus camanchaca sp. nov. A new species Proschoengastia antarctica sp. nov., which is described from American mink Neovison vison on Navarino Island (Region of Magallanes and Antártica Chilena), is the most southerly chigger species, found at the distance of about 1000 km from the continent of Antarctica. Whartonacarus chaetosus (Brennan and Jones, 1961) comb. nov., which was described from Peru, is for the first time recorded in Chile (Atacama Region) and on Microlophus atacamensis. A new combination Proschoengastia macrochaeta (Brennan and Jones, 1961) comb. nov. is established. The genus Morelacarus Vercammen-Grandjean, 1973 previously known from Mexico and southwestern USA is for the first time recorded in Chile. A review of all previously described Chilean chiggers and a key to Eutrombicula species from Chile are provided. In all, 22 species from 13 genera were recorded in Chile, of which only one species (Whartonacarus chaetosus) is known outside the country.

  1. Molecular characterization of thyroid hormone receptors from the leopard gecko, and their differential expression in the skin.

    PubMed

    Kanaho, Yoh-Ichiro; Endo, Daisuke; Park, Min Kyun

    2006-06-01

    Thyroid hormones (THs) play crucial roles in various developmental and physiological processes in vertebrates, including squamate reptiles. The effect of THs on shedding frequency is interesting in Squamata, since the effects on lizards are quite the reverse of those in snakes: injection of thyroxine increases shedding frequency in lizards, but decreases it in snakes. However, the mechanism underlying this differential effect remains unclear. To facilitate the investigation of the molecular mechanism of the physiological functions of THs in Squamata, their two specific receptor (TRalpha and beta) cDNAs, which are members of the nuclear hormone receptor superfamily, were cloned from a lizard, the leopard gecko, Eublepharis macularius. This is the first molecular cloning of thyroid hormone receptors (TRs) from reptiles. The deduced amino acid sequences showed high identity with those of other species, especially in the C and E/F domains, which are characteristic domains in nuclear hormone receptors. Expression analysis revealed that TRs were widely expressed in many tissues and organs, as in other animals. To analyze their role in the skin, temporal expression analysis was performed by RT-PCR, revealing that the two TRs had opposing expression patterns: TRalpha was expressed more strongly after than before skin shedding, whereas TRbeta was expressed more strongly before than after skin shedding. This provides good evidence that THs play important roles in the skin, and that the roles of their two receptor isoforms are distinct from each other.

  2. Snakes antibodies.

    PubMed

    Gambón-Deza, Francisco; Sánchez-Espinel, Christian; Mirete-Bachiller, Serafín; Magadán-Mompó, Susana

    2012-09-01

    Immunoglobulins are basic molecules of the immune system of vertebrates. In previous studies we described the immunoglobulins found in two squamata reptiles, Anolis carolinensis and Eublepharis macularius. Snakes are squamata reptiles too but they have undergone an extreme evolutionary process. We therefore wanted to know how these changes affected their immunoglobulin coding genes. To perform this analysis we studied five snake transcriptomes and two genome draft sequences. Sequences coding for immunoglobulin M (IgM), immunoglobulin D (IgD) and two classes of immunoglobulin Y (IgY - named IgYa and IgYb-) were found in all of them. Moreover, the Thamnophis elegans transcriptome and Python molurus genome draft sequences showed a third class of IgY, the IgYc, whose constant region only presents three domains and lacks the CH2. All data suggest that the IgYb is the evolutionary origin of this IgYc. An exhaustive search of the light chains were carried out, being lambda the only light chain found in snakes. The results provide a clear picture of the immunoglobulins present in the suborder Serpentes.

  3. Intra- and interspecific density-dependent effects on growth in helminth parasites of the cormorant, Phalacrocorax carbo sinensis.

    PubMed

    Dezfuli, B S; Volponi, S; Beltrami, I; Poulin, R

    2002-05-01

    The action of intra- and interspecific competition, mediated by density-dependent effects on growth, was investigated among the 3 helminth species found in the alimentary tract of 104 cormorants, Phalacrocorax carbo sinensis. Intraspecific density-dependent effects on worm sizes were observed in the abundant nematode Contracaecum rudolphii, as shown by a negative correlation between mean worm size and intensity of infection. Higher intensities of infection by C. rudolphii were also associated with more variable worm sizes in the nematode Syncuaria squamata, suggesting a one-sided and density-dependent interspecific effect. There was also clear evidence of some form of negative interaction between the nematode S. squamata and the acanthocephalan Southwellina hispida from two fronts. First, there was a strong negative correlation between the intensities of infection of the 2 species across hosts. Second, sizes of worms of 1 species became more variable as the number of worms of the other species per host increased, and vice versa. This interspecific density-dependent effect on growth was thus apparently symmetrical. We also found evidence that worm size is a predictor of egg output in the 3 helminth species, indicating that intra- and interspecific density-dependent effects on growth can affect population dynamics in these worms. These results illustrate the complex nature of density dependence in helminth growth, and how its effects can act both within and among species.

  4. Genomic V exons from whole genome shotgun data in reptiles.

    PubMed

    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).

  5. A new squamate lizard from the Upper Cretaceous Adamantina Formation (Bauru Group), São Paulo State, Brazil.

    PubMed

    Nava, William R; Martinelli, Agustín G

    2011-03-01

    The record of non-mosasaur squamates (Reptilia, Squamata) is sparse in the Cretaceus fossil record of Brazil and include six putative reports, three from the Aptian-Albian of the Araripe Basin (Tijubina pontei Bonfim-Júnior and Marques, Olindalacerta brasiliensis Evans and Yabumoto, and a lizard indet.) and three from the Upper Cretaceous of the Bauru Group (Pristiguana brasiliensis Estes and Price, Anilioidae gen. et sp. indet., and Squamata gen. et sp. indet.). In this contribution, a new genus and species of lizard, Brasiliguana prudentis gen. et sp. nov., is described based on an isolated left maxilla with teeth. The material was discovered in an outcrop of the Upper Cretaceous Adamantina Formation (Bauru Group) located in the proximity of Presidente Prudente Municipality, São Paulo State, Brazil. The new taxon is considered a basal non-Priscagamidae+Acrodonta iguanian based on the presence of a weakly inclined anterior margin of the maxillary nasal process and maxillary tooth shape and tooth implantation similar to that of iguanians rather than of other lizard groups (e.g. teiids). This finding significantly increases the squamate lizard diversity of South America, which is still poorly understood and sparsely represented in the fossil record.

  6. Mass extinction of lizards and snakes at the Cretaceous-Paleogene boundary.

    PubMed

    Longrich, Nicholas R; Bhullar, Bhart-Anjan S; Gauthier, Jacques A

    2012-12-26

    The Cretaceous-Paleogene (K-Pg) boundary is marked by a major mass extinction, yet this event is thought to have had little effect on the diversity of lizards and snakes (Squamata). A revision of fossil squamates from the Maastrichtian and Paleocene of North America shows that lizards and snakes suffered a devastating mass extinction coinciding with the Chicxulub asteroid impact. Species-level extinction was 83%, and the K-Pg event resulted in the elimination of many lizard groups and a dramatic decrease in morphological disparity. Survival was associated with small body size and perhaps large geographic range. The recovery was prolonged; diversity did not approach Cretaceous levels until 10 My after the extinction, and resulted in a dramatic change in faunal composition. The squamate fossil record shows that the end-Cretaceous mass extinction was far more severe than previously believed, and underscores the role played by mass extinctions in driving diversification.

  7. Tikiguania and the antiquity of squamate reptiles (lizards and snakes).

    PubMed

    Hutchinson, Mark N; Skinner, Adam; Lee, Michael S Y

    2012-08-23

    Tikiguania estesi is widely accepted to be the earliest member of Squamata, the reptile group that includes lizards and snakes. It is based on a lower jaw from the Late Triassic of India, described as a primitive lizard related to agamids and chamaeleons. However, Tikiguania is almost indistinguishable from living agamids; a combined phylogenetic analysis of morphological and molecular data places it with draconines, a prominent component of the modern Asian herpetofauna. It is unlikely that living agamids have retained the Tikiguania morphotype unchanged for over 216 Myr; it is much more conceivable that Tikiguania is a Quaternary or Late Tertiary agamid that was preserved in sediments derived from the Triassic beds that have a broad superficial exposure. This removes the only fossil evidence for lizards in the Triassic. Studies that have employed Tikiguana for evolutionary, biogeographical and molecular dating inferences need to be reassessed.

  8. Mass extinction of lizards and snakes at the Cretaceous-Paleogene boundary

    NASA Astrophysics Data System (ADS)

    Longrich, Nicholas R.; Bhullar, Bhart-Anjan S.; Gauthier, Jacques A.

    2012-12-01

    The Cretaceous-Paleogene (K-Pg) boundary is marked by a major mass extinction, yet this event is thought to have had little effect on the diversity of lizards and snakes (Squamata). A revision of fossil squamates from the Maastrichtian and Paleocene of North America shows that lizards and snakes suffered a devastating mass extinction coinciding with the Chicxulub asteroid impact. Species-level extinction was 83%, and the K-Pg event resulted in the elimination of many lizard groups and a dramatic decrease in morphological disparity. Survival was associated with small body size and perhaps large geographic range. The recovery was prolonged; diversity did not approach Cretaceous levels until 10 My after the extinction, and resulted in a dramatic change in faunal composition. The squamate fossil record shows that the end-Cretaceous mass extinction was far more severe than previously believed, and underscores the role played by mass extinctions in driving diversification.

  9. Histology of the Skin of Three Limbless Squamates Dwelling in Mesic and Arid Environments.

    PubMed

    Allam, Ahmed A; Daza, Juan D; Abo-Eleneen, Rasha E

    2016-07-01

    The skin of limbless squamates has an increased contact with the substrate compared with limbed counterparts. Comparatively, the contact with the substrate is intensified in fossorial species, where the whole circumference of the body interacts with the soil during underground locomotion. Although fossoriality in Squamata, specifically lizards and snakes, has been studied ecologically and morphologically (e.g., osteological changes), not enough detail is yet available regarding changes in organs critical for underground lifestyle such as the skin. Here we used histological and microscopical techniques (scanning electron microscopy and transmission electron microscopy) to uncover the structural detail of the epidermis and dermis in three limbless reptiles, the amphisbaenian Diplometopon zarudnyi, and two snakes, Indotyphlops braminus (Typhlopidae) and Cerastes cerastes (Viperidae). The skin of these taxa shows pronounced morphological diversity, which is likely associated to different environmental and functional demands upon these reptiles. Anat Rec, 299:979-989, 2016. © 2016 Wiley Periodicals, Inc.

  10. Nasal mites of the subfamily Speleognathinae (Ereynetidae) from birds in Texas.

    PubMed

    Pence, D B; Casto, S D

    1976-06-01

    Nasal mites of the subfamily Speleognathinae were recovered from several species of birds in Texas. New host records include Ophthalmophagus striatus (Crossley) 1952 from Columbigallina passerina, Boydaia clarki Fain 1963 from Callipepla squamata, Boydaia falconis Fain 1956 from Falco sparverius, and Boydaia tyrannus Ford 1959 from Myiarchus cinerascens. Also recovered was Astrida coccyzae Pence 1972 from Coccyzus americanus. Boydaia pheucticola sp. n. from Pheucticus melanocephalus is described. It differs from similar species in the adult female by having the coxal setae formula 2-1-2-0, sensillae clavate but not globose or subglobose, and interior seta on coxa I reduced in size but not vestigial. The larva is differentiated by the modified legs II with one long recurved hooklike claw and a shorter curved claw.

  11. New data on Pleistocene and Holocene herpetofauna of Marie Galante (Blanchard Cave, Guadeloupe Islands, French West Indies): Insular faunal turnover and human impact

    NASA Astrophysics Data System (ADS)

    Bailon, S.; Bochaton, C.; Lenoble, A.

    2015-11-01

    This work presents the herpetofaunal remains collected from Blanchard Cave (Marie-Galante, Guadeloupe Archipelago). This site has yielded the oldest stratigraphic layers (around 40,000 BP) of the island, along with data concerning the herpetofaunal biodiversity of the island from the Late Pleistocene to pre-Columbian and modern times. The study of these fossil remains reveals the presence of at least 11 amphibian and squamata taxa (Eleutherodactylus cf. martinicensis, Iguana sp., Anolis ferreus, Leiocephalus cf. cuneus, Thecadactylus cf. rapicauda, cf. Capitellum mariagalantae, Ameiva sp., cf. Antillotyphlops, Boa sp., Alsophis sp. and Colubridae sp. 2) during the Late Pleistocene and Holocene on Marie-Galante Island and provides new evidence concerning extinction times and the introduced or native status of taxa. This study also reveals that this bone assemblage is the result of diverse accumulation processes and provides new morphological data on the past herpetofauna of Marie-Galante.

  12. Contributions to the knowledge of amphibians and reptiles from Volta Grande do Xingu, northern Brazil.

    PubMed

    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.

  13. Comparative reproductive and physiological responses of northern bobwhite and scaled quail to water deprivation

    USGS Publications Warehouse

    Giuliano, W.M.; Patino, R.; Lutz, R.S.

    1998-01-01

    We compared reproductive and physiological responses of captive female northern bobwhite (Colinus virginianus) and scaled quail (Callipepla squamata) under control and water deprivation conditions. Scaled quail required less food and water to reproduce successfully under control conditions than northern bobwhite. Additionally, in scaled quail, serum osmolality levels and kidney mass were unaffected by water deprivation, whereas in northern bobwhite, serum osmolality levels increased and kidney mass declined. This finding indicates that scaled quail may have osmoregulatory abilities superior to those of northern bobwhite. Under control conditions, northern bobwhite gained more body mass and produced more but smaller eggs than scaled quail. Under water deprivation conditions, northern bobwhite lost more body mass but had more laying bens with a higher rate of egg production than scaled quail. Our data suggest that northern bobwhite allocated more resources to reproduction than to body maintenance, while scaled quail apparently forego reproduction in favor of body maintenance during water deprivation conditions.

  14. Synergic effects of tryptamine and octopamine on ophiuroid luminescence (Echinodermata).

    PubMed

    Vanderlinden, C; Mallefet, J

    2004-10-01

    In ophiuroids, bioluminescence is under nervous control. Previous studies have shown that acetylcholine is the main neurotransmitter triggering light emission in Amphipholis squamata and Amphiura filiformis. By contrast, none of the neurotransmitters tested so far induced luminescence in two other ophiuroid species, Ophiopsila aranea and Ophiopsila californica. The aim of this work was thus to investigate the putative involvement of two biogenic amines, tryptamine and octopamine, in light emission of three ophiuroid species. A. filiformis responds to both tryptamine and octopamine, mainly on its arm segments, while O. californica only responds to tryptamine stimulation. By contrast, tryptamine and octopamine do not seem to be involved in O. aranea luminescence control since none of these substances induced light emission in this species. The synergic effects of several other drugs with tryptamine and octopamine were also tested.

  15. A new species of insular Rock Gecko (Genus Cnemaspis Strauch, 1887) from the Bidong Archipelago, Terengganu, Peninsular Malaysia.

    PubMed

    Grismer, L Lee; Wood, Perry L; Ahmad, Amirrudin B; Sumarli, Alexandra S-I; Vazquez, Jessika J; Ismail, Lukman H B; Nance, Ronald; Mohd-Amin, Muhammad Afif B; Othman, Mohamad N A B; Rizaijessika, Syed A; Kuss, Maria; Murdoch, Matthew; Cobos, Anthony

    2014-01-24

    A new insular species Cnemaspis bidongensis sp. nov. (Squamata: Gekkonidae), is described from Pulau Bidong, Terengganu, Peninsular Malaysia and bears a unique suite of morphological and color pattern characters that differentiate it from all other congeners. Cnemaspis bidongensis sp. nov. is the sister species to C. kendallii (Gray) and represents the fifth insular endemic species of Cnemaspis on archipelagos along the east coast of Peninsular Malaysia. This species survived massive deforestation of the small island of Bidong (260 ha) from the mid 1970s to the early 1990s when the island served as a Vietnamese refugee camp and harbored as many as 40,000 people at one time. We hypothesize that this species' generalized lifestyle contributed to its survival, allowing it to seek refuge in rocky microhabitats.

  16. Two new Japanese species of Gastrotricha (Chaetonotida, Chaetonotidae, Lepidodermella and Dichaeturidae, Dichaetura), with Comments on the Diversity of Gastrotrichs in Rice Paddies.

    PubMed

    Suzuki, Takahito G; Maeda, Masako; Furuya, Hidetaka

    2013-01-01

    Two new species of freshwater gastrotrichs are described from rice paddies in Otsu, Shiga, Japan. Lepidodermella acantholepida n. sp. is a medium sized species attaining a length of 145 microum, scales are flattened ovals and similar to those of L. squamata except that two dorsal scales near the furca have a claw-like spine. Dichaeturafilispina n. sp. is a medium sized species attaining a length of 185 microm, characterized by a thin, fiber-like spine, a spined furca with a constriction near its base and an elongate body. A total of 44 species (seven genera) including two new species were found in the rice paddies. The diversity of rice paddy gastrotrichs is briefly discussed.

  17. A new species of Ornithodoros (Acari: Argasidae), parasite of Microlophus spp. (Reptilia: Tropiduridae) from northern Chile.

    PubMed

    Venzal, José M; Nava, Santiago; González-Acuña, Daniel; Mangold, Atilio J; Muñoz-Leal, Sebastián; Lado, Paula; Guglielmone, Alberto A

    2013-02-01

    A new species, Ornithodoros microlophi (Acari: Argasidae), belonging to the subgenus Alectorobius is described from larvae collected on the lizards Microlophus atacamensis (Donoso-Barros, 1966) and Microlophus quadrivittatus (Tschudi, 1845) (Squamata: Tropiduridae) in continental and insular localities from northern Chile. Larvae of O. microlophi can be distinguished from other Neotropical species of the genus Ornithodoros by a combination of the following characters, namely 10 pairs of ventral setae, venter with 6 pairs of sternal setae, dorsal plate pyriform, 19-21 pairs of dorsal setae (typically 20), 13 pairs are dorsolateral and 7 pairs are central, and hypostome with dental formula 4/4 in medial portion and apex pointed. Phylogenetic analysis of 16S rDNA sequences suggests that O. microlophi represents an independent lineage within Neotropical species of the Argasidae.

  18. Live birth among Iguanian lizards predates Pliocene--Pleistocene glaciations.

    PubMed

    Schulte, James A; Moreno-Roark, Franck

    2010-04-23

    Among tetrapods, viviparity is estimated to have evolved independently within Squamata (lizards and snakes) more than 100 times, most frequently in species occupying cold climate environments. Because of this relationship with cold climates, it is sometimes assumed that many origins of squamate viviparity occurred over the past 2.5-4 Myr during the Pliocene-Pleistocene glaciations; however, this hypothesis is untested. Divergence-dating analysis on a 733-species tree of Iguanian lizards recovers 20 independent lineages that have evolved viviparity, of which 13 multispecies groups derived live birth prior to glacial advances (8-66 Myr ago). These results place the transitions from egg-laying to live birth among squamates in a well-supported historical context to facilitate examination of the underlying phenotypic and genetic changes associated with this complex shift in reproduction.

  19. Development and characterization of nine microsatellites for an endangered tree, Pinus wangii (Pinaceae)1

    PubMed Central

    Dou, Jing-Jing; Zhou, Ren-Chao; Tang, An-Jun; Ge, Xue-Jun; Wu, Wei

    2013-01-01

    • Premise of the study: Pinus wangii is an endemic and endangered species in southwestern China, and microsatellite primers were developed to characterize its genetic diversity and population structure. • Methods and Results: Using the Fast Isolation by AFLP of Sequences COntaining repeats (FIASCO) protocol, nine sets of microsatellite primers were developed in P. wangii. One population with 26 individuals of P. wangii, as well as 11 individuals each for two congeneric species, P. taiwanensis and P. squamata, were used to test their polymorphism and transferability. The number of alleles per locus ranged from one to seven with an average of 3.7, and the observed heterozygosity and expected heterozygosity ranged from 0 to 0.91 and 0 to 0.75, respectively. • Conclusions: We developed nine sets of polymorphic microsatellite loci that are suitable for investigating genetic diversity and population structure of P. wangii, and these markers may be useful for other Pinus species. PMID:25202511

  20. Reptiles.

    PubMed

    Shine, Richard

    2013-03-18

    Most small children can tell you that 'reptiles' are the snakes, lizards, crocodiles, and turtles (perhaps with the dinosaurs thrown in) - suggesting that it's easy to tell the difference between reptiles and other animals. Unfortunately, evolutionary biologists struggle with the same task, because phylogenetic analysis tells us loud and clear that these different types of what we loosely call 'reptiles' are not particularly closely related to each other (Figure 1). On the evolutionary tree, some of them (dinosaurs, crocodiles) are much more closely related to birds than to the other animals that we call reptiles. Other reptiles are the descendants of very ancient lineages; for example, turtles separated from the other reptiles, including the now-dominant Squamata (lizards and snakes), at least 200 million years ago. And another 200-million-year-old lineage has left just a single survivor, a lizard-like creature (the tuatara), on a few islands in New Zealand.

  1. Biochemical Characterization, Action on Macrophages, and Superoxide Anion Production of Four Basic Phospholipases A2 from Panamanian Bothrops asper Snake Venom

    PubMed Central

    Rueda, Aristides Quintero; Rodríguez, Isela González; Arantes, Eliane C.; Setúbal, Sulamita S.; Calderon, Leonardo de A.; Zuliani, Juliana P.; Stábeli, Rodrigo G.; Soares, Andreimar M.

    2013-01-01

    Bothrops asper (Squamata: Viperidae) is the most important venomous snake in Central America, being responsible for the majority of snakebite accidents. Four basic PLA2s (pMTX-I to -IV) were purified from crude venom by a single-step chromatography using a CM-Sepharose ion-exchange column (1.5 × 15 cm). Analysis of the N-terminal sequence demonstrated that pMTX-I and III belong to the catalytically active Asp49 phospholipase A2 subclass, whereas pMTX-II and IV belong to the enzymatically inactive Lys49 PLA2s-like subclass. The PLA2s isolated from Panama Bothrops asper venom (pMTX-I, II, III, and IV) are able to induce myotoxic activity, inflammatory reaction mainly leukocyte migration to the muscle, and induce J774A.1 macrophages activation to start phagocytic activity and superoxide production. PMID:23509779

  2. Macrobenthic zonation patterns along a morphodynamical continuum of macrotidal, low tide bar/rip and ultra-dissipative sandy beaches

    NASA Astrophysics Data System (ADS)

    Degraer, S.; Volckaert, A.; Vincx, M.

    2003-03-01

    The species composition, densities, biomass and zonation patterns of the macrobenthos of sandy beaches are greatly influenced by the morphodynamics and morphology of the beaches. Macrobenthic zonation patterns along a small-scale morphodynamic gradient, comprising eight Belgian beach sites, were investigated. By taking into account the dimensionless fall velocity ( Ω) and the relative tidal range, the beach sites were ordered along the gradient from the ultra-dissipative beach type (UD) to the low tide bar/rip beach type (LTBR). The resulting beach state index varied between 1.8 and 4.2 and the beach profiles were related with the beaches' morphodynamic state. In total 35 macrobenthic species, mainly polychaetes and crustaceans, were encountered, varying between 19 and 23 species per beach site. The species composition was quite similar among beach sites, with Scolelepis squamata being abundant at all eight sites. Furthermore, the macrobenthic distribution patterns were mainly related to elevation at all beach sites. Some remarkable difference in metrics, largely related to the beach morphodynamics and the consequent hydrodynamics, were found. At the hydrodynamically benign and consequently macrobenthos-rich UD beaches, the highest macrobenthic densities and biomass occurred on the upper beach, while at the hydrodynamically harsh and thus macrobenthos-poor LTBR beaches, the maximum densities and biomass occurred lower on the beach. Species, typically occurring on the upper UD beaches, such as Eurydice pulchra, S. squamata, and Bathyporeia sarsi, were restricted to the sub-optimal middle and lower beach zone at LTBR beaches. Only Bathyporeia pilosa was found on the upper beach of both UD and LTBR beaches. The more robust polychaete Ophelia rathkei and the interstitial polychaete Hesionides arenaria were exclusively found in the hydrodynamically harsh conditions of the middle LTBR beach zone.

  3. Novel Approaches for Phylogenetic Inference from Morphological Data and Total-Evidence Dating in Squamate Reptiles (Lizards, Snakes, and Amphisbaenians).

    PubMed

    Pyron, R Alexander

    2016-08-11

    Here, I combine previously underutilized models and priors to perform more biologically realistic phylogenetic inference from morphological data, with an example from squamate reptiles. When coding morphological characters, it is often possible to denote ordered states with explicit reference to observed or hypothetical ancestral conditions. Using this logic, we can integrate across character-state labels and estimate meaningful rates of forward and backward transitions from plesiomorphy to apomorphy. I refer to this approach as MkA, for "asymmetric." The MkA model incorporates the biological reality of limited reversal for many phylogenetically informative characters, and significantly increases likelihoods in the empirical data sets. Despite this, the phylogeny of Squamata remains contentious. Total-evidence analyses using combined morphological and molecular data and the MkA approach tend toward recent consensus estimates supporting a nested Iguania. However, support for this topology is not unambiguous across data sets or analyses, and no mechanism has been proposed to explain the widespread incongruence between partitions, or the hidden support for various topologies in those partitions. Furthermore, different morphological data sets produced by different authors contain both different characters and different states for the same or similar characters, resulting in drastically different placements for many important fossil lineages. Effort is needed to standardize ontology for morphology, resolve incongruence, and estimate a robust phylogeny. The MkA approach provides a preliminary avenue for investigating morphological evolution while accounting for temporal evidence and asymmetry in character-state changes. [Congruence; convergence; dating; molecular discordance; morphological phylogenetics; reversals; Squamata; total evidence.].

  4. Reptilian Transcriptomes v2.0: An Extensive Resource for Sauropsida Genomics and Transcriptomics

    PubMed Central

    Tzika, Athanasia C.; Ullate-Agote, Asier; Grbic, Djordje; Milinkovitch, Michel C.

    2015-01-01

    Despite the availability of deep-sequencing techniques, genomic and transcriptomic data remain unevenly distributed across phylogenetic groups. For example, reptiles are poorly represented in sequence databases, hindering functional evolutionary and developmental studies in these lineages substantially more diverse than mammals. In addition, different studies use different assembly and annotation protocols, inhibiting meaningful comparisons. Here, we present the “Reptilian Transcriptomes Database 2.0,” which provides extensive annotation of transcriptomes and genomes from species covering the major reptilian lineages. To this end, we sequenced normalized complementary DNA libraries of multiple adult tissues and various embryonic stages of the leopard gecko and the corn snake and gathered published reptilian sequence data sets from representatives of the four extant orders of reptiles: Squamata (snakes and lizards), the tuatara, crocodiles, and turtles. The LANE runner 2.0 software was implemented to annotate all assemblies within a single integrated pipeline. We show that this approach increases the annotation completeness of the assembled transcriptomes/genomes. We then built large concatenated protein alignments of single-copy genes and inferred phylogenetic trees that support the positions of turtles and the tuatara as sister groups of Archosauria and Squamata, respectively. The Reptilian Transcriptomes Database 2.0 resource will be updated to include selected new data sets as they become available, thus making it a reference for differential expression studies, comparative genomics and transcriptomics, linkage mapping, molecular ecology, and phylogenomic analyses involving reptiles. The database is available at www.reptilian-transcriptomes.org and can be enquired using a wwwblast server installed at the University of Geneva. PMID:26133641

  5. Incidence, causes and consequences of pregnancy failure in viviparous lizards: implications for research and conservation settings.

    PubMed

    Hare, Kelly M; Cree, Alison

    2010-01-01

    Research on the causes of pregnancy failure in vertebrates has historically been mammal-focussed. However, live-birth (viviparity) has evolved multiple times, and is present in all other vertebrate taxa except Aves and Agnatha. Viviparous lizards (O. Squamata, excluding snakes and amphisbaenians) provide a valuable experimental group when studying major evolutionary events and some are also species of high conservation value. Consequently, both researchers and herpetoculturists often require high reproductive output from captive-held lizards. We reviewed the literature to determine potential or known causes of pregnancy failure for captive lizards. Pregnancy success across species averages approximately 86%, but varies extensively and does not appear to be related to embryonic stage when brought into captivity or level of placentation. Causes of pregnancy failure also vary among species, but correct thermal environments are vital to success, and providing adequate nutrition before vitellogenesis increases the number of viable offspring. A coordinated sequence of hormonal changes involving both pro-pregnancy and pro-labour factors is important for successful pregnancies, although uncertainty remains around the maternal concentrations of corticosterone that allow successful development. Several research areas commonly studied in mammals have yet to be explored or fully addressed in pregnant lizards, including impacts of toxins, parasites, UV light and nutritional quality. As viviparity has evolved over 100 times in lizards, and many different levels of placentation exist, pregnant lizards provide valuable models for studies in ecology and evolution and offer a useful comparison for studies on other viviparous vertebrates.

  6. Observations on the sexual segment of the kidney of snakes with emphasis on ultrastructure in the yellow-bellied sea snake, Pelamis platurus.

    PubMed

    Sever, David M; Rheubert, Justin L; Gautreaux, Jillian; Hill, Toren G; Freeborn, Layla R

    2012-05-01

    The sexual segment of the kidney (SSK) is an accessory sex structure in male lizards and snakes (Squamata). We describe histology of the SSK in 12 species of snakes, including one from the basal Scolecophidia, Leptotyphlops dulcis, and from the more advanced Alethinophidia, species from the Acrochordidae (Acrochordus granulatus), Homalopsidae (Cerberus rynchops), Uropeltidae (Teretrurus sanguineus), and eight species from the Elapidae, including six species of sea snakes. We also describe the ultrastructure of the SSK of the sea snake, Pelamis platurus. The SSK of L. dulcis does not include the ureter but does include distal convoluted tubules (DCTs) and collecting ducts. In all other snakes examined, the SSK is limited to the DCTs and does not differ in histology by any consistent character. We found apparently mature individuals of several species with inactive SSKs. Hypertrophied SSKs give positive reactions for protein secretions but variable reactions for carbohydrates. Ultrastructure of the SSK of P. platurus reveals nuclei situated medially in the epithelium and mature electron dense secretory vacuoles in other areas of the cytoplasm. Product release is apocrine. Junctional complexes only occur at the luminal border, and intercellular canaliculi become widened and are open basally. No cytologically unique characters occur in the SSK of P. platurus. The ancestral condition of the SSK in squamates is the presence of simple columnar epithelium specialized for secretion of a protein + carbohydrate product that matures and is released seasonally.

  7. Clutch size in the tropical scincid lizard Emoia sanfordi, a species endemic to the Vanuatu Archipelago.

    PubMed

    Hamilton, Alison Madeline; Eckstut, Mallory Elizabeth; Klein, Elaine Renee; Austin, Christopher Cowell

    2008-08-01

    The majority of species in the scincid genus Emoia (Squamata: Scincidae) have a fixed clutch size of two eggs per clutch and produce between two and four clutches per year. One lineage within Emoia, the Emoia samoensis species group, consists of 13 species occurring in Melanesia and the islands of the southwestern Pacific Ocean, and exhibits variation in clutch size, with previously reported clutch sizes of two to five eggs. Little is known about reproduction in several members of this lineage including Emoia sanfordi, a large-bodied lizard endemic to the archipelago of Vanuatu in the South Pacific. We analyzed reproduction and clutch size in E. sanfordi females and discovered that there is a substantial amount of intraspecific variation, with clutch size ranging from two to seven eggs, with a modal clutch size of five eggs. Females were reproductively active throughout the study period of June through October and appear to be laying multiple clutches. The variation in clutch size seen in E. sanfordi is congruent with the variation previously reported within other closely related species.

  8. Evolutionary Diversification of the Lizard Genus Bassiana (Scincidae) across Southern Australia

    PubMed Central

    Dubey, Sylvain; Shine, Richard

    2010-01-01

    Background Relatively recent (Plio-Pleistocene) climatic variations had strong impacts on the fauna and flora of temperate-zone North America and Europe; genetic analyses suggest that many lineages were restricted to unglaciated refuges during this time, and have expanded their ranges since then. Temperate-zone Australia experienced less severe glaciation, suggesting that patterns of genetic structure among species may reflect older (aridity-driven) divergence events rather than Plio-Pleistocene (thermally-mediated) divergences. The lizard genus Bassiana (Squamata, Scincidae) contains three species that occur across a wide area of southern Australia (including Tasmania), rendering them ideally-suited to studies on the impact of past climatic fluctuations. Methodology/Principal Findings We performed molecular phylogenetic and dating analyses using two partial mitochondrial genes (ND2 and ND4) of 97 samples of Bassiana spp. Our results reveal a pattern of diversification beginning in the Middle Miocene, with intraspecific diversification arising from 5.7 to 1.7 million years ago in the Upper Miocene-Lower Pleistocene. Conclusions/Significance In contrast to the temperate-zone Northern Hemisphere biota, patterns of evolutionary diversification within southern Australian taxa appear to reflect geologically ancient events, mostly relating to east-west discontinuities imposed by aridity rather than (as is the case in Europe and North America) relatively recent recolonisation of northern regions from unglaciated refugia to the south. PMID:20886050

  9. Paenibacillus sabinae sp. nov., a nitrogen-fixing species isolated from the rhizosphere soils of shrubs.

    PubMed

    Ma, Yuchao; Xia, Zhiqiang; Liu, Xuming; Chen, Sanfeng

    2007-01-01

    Five novel endospore-forming, nitrogen-fixing bacterial strains were isolated from the rhizosphere soils of plants of the species Sabina squamata, Weigela florida and Zanthoxylum simulans. A phylogenetic analysis based on 16S rRNA gene sequences revealed that the five strains formed a distinct cluster within the genus Paenibacillus. These novel strains showed the highest levels (96.2-98.2 %) of 16S rRNA gene sequence similarity with Paenibacillus azotofixans. However, the DNA-DNA relatedness between these novel strains and P. azotofixans was 12.9-29.5 %. The DNA G+C contents of the five strains were found to be 51.9-52.9 mol%. Phenotypic analyses showed that a significant feature of the novel strains (differentiating them from P. azotofixans and other Paenibacillus species) is that all of them were unable to produce acid and gas from various carbohydrates such as glucose, sucrose, lactose and fructose. Anteiso-branched C(15 : 0) was the major fatty acid present in the novel type strain. On the basis of these data, the five novel strains represent a novel species of the genus Paenibacillus, for which the name Paenibacillus sabinae sp. nov. is proposed. The type strain is T27(T) (=CCBAU 10202(T)=DSM 17841(T)).

  10. Characterization and distribution of retrotransposons and simple sequence repeats in the bovine genome

    PubMed Central

    Adelson, David L.; Raison, Joy M.; Edgar, Robert C.

    2009-01-01

    Interspersed repeat composition and distribution in mammals have been best characterized in the human and mouse genomes. The bovine genome contains typical eutherian mammal repeats, but also has a significant number of long interspersed nuclear element RTE (BovB) elements proposed to have been horizontally transferred from squamata. Our analysis of the BovB repeats has indicated that only a few of them are currently likely to retrotranspose in cattle. However, bovine L1 repeats (L1 BT) have many likely active copies. Comparison of substitution rates for BovB and L1 BT indicates that L1 BT is a younger repeat family than BovB. In contrast to mouse and human, L1 occurrence is not negatively correlated with G+C content. However, BovB, Bov A2, ART2A, and Bov-tA are negatively correlated with G+C, although Bov-tAs correlation is weaker. Also, by performing genome wide correlation analysis of interspersed and simple sequence repeats, we have identified genome territories by repeat content that appear to define ancestral vs. ruminant-specific genomic regions. These ancestral regions, enriched with L2 and MIR repeats, are largely conserved between bovine and human. PMID:19625614

  11. Persistent effect of incubation temperature on stress-induced behavior in the Yucatan banded gecko (Coleonyx elegans).

    PubMed

    Trnik, Marian; Albrechtová, Jana; Kratochvíl, Lukáš

    2011-02-01

    Although variability in behavioral traits within animal populations is well documented, the mechanisms maintaining that variability are still insufficiently known. In this study, we examined whether differences in thermal environment during egg incubation can permanently organize nonsocial behavior across different contexts and situations in a lizard species. We incubated eggs of the Yucatan banded gecko, Coleonyx elegans (Squamata: Gekkota: Eublepharidae) at 3 constant temperatures (26, 28, and 30 °C) and raised juveniles separately under the same conditions until adulthood. We then subjected them to 3 behavioral tests within 2 different contexts: an open-field test and a test of antipredator behavior (stressful context) as well as a test of feeding behavior (nonstressful context). Individuals of both sexes incubated at 30 °C were consistently less active and showed lower frequencies of several stereotypic behaviors in the stressful contexts than did individuals incubated at 26 and 28 °C. The test of feeding behavior revealed no significant effect of incubation temperature on geckos' behavior. Thus, our study demonstrates that developmental plasticity may play an important role in producing variability in stress-induced behavior in lizards.

  12. Adaptation to life in aeolian sand: how the sandfish lizard, Scincus scincus, prevents sand particles from entering its lungs

    PubMed Central

    Vihar, Boštjan; Günther, Mathias; Huemer, Michaela; Riedl, Martin; Shamiyeh, Stephanie; Mayrhofer, Bernhard; Böhme, Wolfgang; Baumgartner, Werner

    2016-01-01

    ABSTRACT The sandfish lizard, Scincus scincus (Squamata: Scincidae), spends nearly its whole life in aeolian sand and only comes to the surface for foraging, defecating and mating. It is not yet understood how the animal can respire without sand particles entering its respiratory organs when buried under thick layers of sand. In this work, we integrated biological studies, computational calculations and physical experiments to understand this phenomenon. We present a 3D model of the upper respiratory system based on a detailed histological analysis. A 3D-printed version of this model was used in combination with characteristic ventilation patterns for computational calculations and fluid mechanics experiments. By calculating the velocity field, we identified a sharp decrease in velocity in the anterior part of the nasal cavity where mucus and cilia are present. The experiments with the 3D-printed model validate the calculations: particles, if present, were found only in the same area as suggested by the calculations. We postulate that the sandfish has an aerodynamic filtering system; more specifically, that the characteristic morphology of the respiratory channel coupled with specific ventilation patterns prevent particles from entering the lungs. PMID:27852763

  13. A Meta-Analysis of Predation Risk Effects on Pollinator Behaviour

    PubMed Central

    Romero, Gustavo Q.; Antiqueira, Pablo A. P.; Koricheva, Julia

    2011-01-01

    Flower-visiting animals are constantly under predation risk when foraging and hence might be expected to evolve behavioural adaptations to avoid predators. We reviewed the available published and unpublished data to assess the overall effects of predators on pollinator behaviour and to examine sources of variation in these effects. The results of our meta-analysis showed that predation risk significantly decreased flower visitation rates (by 36%) and time spent on flowers (by 51%) by pollinators. The strength of the predator effects depended neither on predator taxa and foraging mode (sit-and-wait or active hunters) nor on pollinator lifestyle (social vs. solitary). However, predator effects differed among pollinator taxa: predator presence reduced flower visitation rates and time spent on flowers by Squamata, Lepidoptera and Hymenoptera, but not by Diptera. Furthermore, larger pollinators showed weaker responses to predation risk, probably because they are more difficult to capture. Presence of live crab spiders on flowers had weaker effects on pollinator behaviour than presence of dead or artificial crab spiders or other objects (e.g. dead bees, spheres), suggesting that predator crypsis may be effective to some extent. These results add to a growing consensus on the importance of considering both predator and pollinator characteristics from a community perspective. PMID:21695187

  14. Jaw adductor muscles across lepidosaurs: a reappraisal.

    PubMed

    Daza, Juan Diego; Diogo, Rui; Johnston, Peter; Abdala, Virginia

    2011-10-01

    The exact homologies of tetrapod jaw muscles remain unresolved, and this provides a barrier for phylogenetic analysis and tracing character evolution. Here, lepidosaur jaw muscles are surveyed using direct examination of species from 23 families and published descriptions of species from 10 families. A revised nomenclature is applied according to proposed homologies with Latimeria. Among lepidosaurs, variation was found in many aspects of jaw muscle anatomy. The superficial layers mm. levator and retractor anguli oris (LAO and RAO) are present in Sphenodon but not all squamates. The external jaw adductor muscles universally present in lepidosaurs are homologous with the main adductor muscle, A2, of Latimeria and include four layers: superficialis (A2-SUP), medialis (A2-M), profundus (A2-PRO), and posterior (A2-PVM). The A2-SUP appears divided in Agamidae, Gekkota, Xantusiidae, and Varanidae. The A2-M is layered lateromedial in lizards but anteroposterior in snakes. The names pseudotemporalis (PS) and pterygomandibularis (PTM) are recommended for subdivisions of the internal adductors of reptiles and amphibians, because the homology of this muscle with the A3' and A3 ″ of Latimeria remains inconclusive. The intramandibularis of lepidosaurs and Latimeria (A-ω) are homologous. The distribution of six jaw muscle characters was found to plot more parsimoniously on phylogenies based on morphological rather than and molecular data. Character mapping indicates that Squamata presents reduction in the divisions of the A2-M, Scincoidea presents reduction or loss of LAO, and two apomorphic features are found for the Gekkota.

  15. At the feet of the dinosaurs: the early history and radiation of lizards.

    PubMed

    Evans, Susan E

    2003-11-01

    Lizards, snakes and amphisbaenians together constitute the Squamata, the largest and most diverse group of living reptiles. Despite their current success, the early squamate fossil record is extremely patchy. The last major survey of squamate palaeontology and evolution was published 20 years ago. Since then, there have been major changes in systematic theory and methodology, as well as a steady trickle of new fossil finds. This review examines our current understanding of the first 150 million years of squamate evolution in the light of the new data and changing ideas. Contrary to previous reports, no squamate fossils are currently documented before the Jurassic. Nonetheless, indirect evidence predicts that squamates had evolved by at least the middle Triassic, and had diversified into existing major lineages before the end of this period. There is thus a major gap in the squamate record at a time when key morphological features were evolving. With the exception of fragmentary remains from Africa and India, Jurassic squamates are known only from localities in northern continents (Laurasia). The situation improves in the Early Cretaceous, but the southern (Gondwanan) record remains extremely poor. This constrains palaeobiogeographic discussion and makes it difficult to predict centres of origin for major squamate clades on the basis of fossil evidence alone. Preliminary mapping of morphological characters onto a consensus tree demonstrates stages in the sequence of acquisition for some characters of the skull and postcranial skeleton, but many crucial stages--most notably those relating to the acquisition of squamate skull kinesis--remain unclear.

  16. Diversity and chemical defense role of culturable non-actinobacterial bacteria isolated from the South China Sea gorgonians.

    PubMed

    Peng, Jiang; Zhang, Xiaoyong; Xu, Xinya; He, Fei; Qi, Shuhua

    2013-04-01

    The diversity of culturable non-actinobacterial (NA) bacteria associated with four species of South China Sea gorgonians was investigated using culture-dependent methods followed by analysis of the bacterial 16S rDNA sequence. A total of 76 bacterial isolates were recovered and identified, which belonged to 21 species of 7 genera, and Bacillus was the most diverse genus. Fifty-one percent of the 76 isolates displayed antibacterial activities, and most of them belonged to the Bacillus genus. From the culture broth of gorgonian-associated Bacillus methylotrophicus SCSGAB0092 isolated from gorgonian Melitodes squamata, 11 antimicrobial lipopeptides including seven surfactins and four iturins were obtained. These results imply that Bacillus strains associated with gorgonians play roles in coral defense mechanisms through producing antimicrobial substances. This study, for the first time, compares the diversity of culturable NA bacterial communities among four species of South China Sea gorgonians and investigates the secondary metabolites of gorgonian-associated B. methylotrophicus SCSGAB0092.

  17. Elucidating the phylogenetic position of Gnathostomulida and first mitochondrial genomes of Gnathostomulida, Gastrotricha and Polycladida (Platyhelminthes).

    PubMed

    Golombek, Anja; Tobergte, Sarah; Struck, Torsten H

    2015-05-01

    Gnathostomulida is a taxon of small marine worms, which exclusively inhabit the interstitium. The evolution of Gnathostomulida has been discussed for decades. Originally regarded as primitive animals with affinities to flatworms, the phylogenetic position of Gnathostomulida has been debated. Given the lack of an anus a close relationship to Platyhelminthes has been maintained (i.e., Plathelminthomorpha hypothesis). Alternative hypotheses proposed Gnathostomulida as being close to Gastrotricha due to the presence of a monociliary epidermis (i.e., Monokonta/Neotrichozoa hypothesis) or to Syndermata based on the complicated jaw apparatus (i.e., Gnathifera hypothesis). Molecular analyses using only few genes were inconclusive. Recent phylogenomic studies brought some progress by placing Gnathostomulida as sister to Syndermata, but support for this relationship was low and depended on the analytical strategy. Herein we present the first data of complete or nearly complete mitochondrial genomes for two gnathostomulids (Gnathostomula paradoxa &G. armata), one gastrotrich (Lepidodermella squamata) and one polyclad flatworm (Stylochoplana maculata) to address the uncertain phylogenetic affinity of Gnathostomulida. Our analyses found Gnathostomulida as sister to Syndermata (Gnathifera hypothesis). Thorough sensitivity analyses addressing taxon instability, branch length heterogeneity (also known as long branch attraction) and base composition heterogeneity showed that the position of Gnathostomulida is consistent across the different analyses and, hence, independent of potential misleading biases. Moreover, by ameliorating these different biases nodal support values could be increased to maximum values. Thus, our data support the hypothesis that the different jaw apparatuses of Syndermata and Gnathostomulida are indeed homologous structures as proposed by the Gnathifera hypothesis.

  18. Checklist of Gastrotricha of the Polish Baltic Sea with the first reports of Heterolepidoderma joermungandri Kånneby, 2011, and Turbanella hyalina Schultze, 1853.

    PubMed

    Kolicka, Małgorzata; Kisielewski, Jacek; Kotwicki, Lech; Zawierucha, Krzysztof; Grzelak, Katarzyna

    2014-09-30

    Gastrotricha is a cosmopolitan phylum of aquatic and semi-terrestrial invertebrates comprising more than 800 described species. Up to now, only five taxonomic and faunistic papers have been published on the gastrotrichs of the Polish Baltic Sea and 27 taxa have been found (including three freshwater, which were found in estuaries). This article presents a complete list of brackish and estuarine Gastrotricha from the Polish Baltic Sea accompanied by localities and the first observations of gastrotrich species inhabiting the underwater macrophytes. Although the group has been studied for more than 150 years, the gastrotrich community of marine macrophytes has not been studied in any great detail. Here we provide data on gastrotrich communities living on macrophytes and also in sandy sediments. In total, nine species were found (seven from sandy sediments, two species from macrophytes). Seven of the species belong to Chaetonotida: Halichaetonotus balticus Kisielewski, 1975, H. lamellatus Kisielewski, 1975, H. schromi Kisielewski, 1975, Heterolepidoderma joermungandri Kånneby, 2011, Lepidodermella squamata (Dujardin, 1841), Xenotrichula intermedia Remane, 1934, and X. velox Remane, 1927(c). Two of species belong to Macrodasyida: Turbanella cornuta Remane, 1925, and T. hyalina Schultze, 1853. H. joermungandri and T. hyalina are new for Polish fauna. Both species correspond with the original descriptions but differ by some morphometric characters. Taxonomic, morphometric, and biogeographic remarks are provided for the new records together with differential interference contrast (DIC) microphotographs.

  19. A revised metric for quantifying body shape in vertebrates.

    PubMed

    Collar, David C; Reynaga, Crystal M; Ward, Andrea B; Mehta, Rita S

    2013-08-01

    Vertebrates exhibit tremendous diversity in body shape, though quantifying this variation has been challenging. In the past, researchers have used simplified metrics that either describe overall shape but reveal little about its anatomical basis or that characterize only a subset of the morphological features that contribute to shape variation. Here, we present a revised metric of body shape, the vertebrate shape index (VSI), which combines the four primary morphological components that lead to shape diversity in vertebrates: head shape, length of the second major body axis (depth or width), and shape of the precaudal and caudal regions of the vertebral column. We illustrate the usefulness of VSI on a data set of 194 species, primarily representing five major vertebrate clades: Actinopterygii, Lissamphibia, Squamata, Aves, and Mammalia. We quantify VSI diversity within each of these clades and, in the course of doing so, show how measurements of the morphological components of VSI can be obtained from radiographs, articulated skeletons, and cleared and stained specimens. We also demonstrate that head shape, secondary body axis, and vertebral characteristics are important independent contributors to body shape diversity, though their importance varies across vertebrate groups. Finally, we present a functional application of VSI to test a hypothesized relationship between body shape and the degree of axial bending associated with locomotor modes in ray-finned fishes. Altogether, our study highlights the promise VSI holds for identifying the morphological variation underlying body shape diversity as well as the selective factors driving shape evolution.

  20. Fetal Membrane Ultrastructure and Development in the Oviparous Milksnake Lampropeltis triangulum (Colubridae) with Reference to Function and Evolution in Snakes.

    PubMed

    Kim, Young K; Blackburn, Daniel G

    2016-07-01

    In eggs of oviparous reptiles, fetal membranes maintain developing embryos through the exchange of respiratory gases and provision of water and calcium. As part of a survey of reptilian fetal membranes, we used scanning electron microscopy to study fetal membrane morphology in the oviparous Pueblan milksnake, Lampropeltis triangulum campbelli. The chorioallantois initially is an avascular structure lined by enlarged chorionic and allantoic epithelia. Upon vascularization, the chorionic epithelium becomes greatly attenuated, enhancing the potential for gas exchange; the allantoic epithelium also flattens. The bilaminar omphalopleure of the yolk sac lacks blood vessels, but it becomes vascularized by allantoic capillaries and transformed into an omphalallantois. Upon regression of the isolated yolk mass, this membrane is converted to chorioallantois, equipping it for gas exchange. Allantoic fluid serves as a water reservoir, and we postulate that it facilitates water uptake by establishing an osmotic gradient. Early in development, epithelia of both the chorion and the omphalopleure show apical microvilli that greatly increase the cell surface area available for water uptake. However, these features are incompatible with gas exchange and are lost as oxygen needs take precedence. A comparison of the fetal membranes to those of other squamate species (both oviparous and viviparous) reveals characteristics that are probably ancestral for snakes, some of which are plesiomorphic for Squamata. The widespread phylogenetic distribution of these features reflects their utility as adaptations that serve functional requirements of squamate embryos.

  1. The impact of land use intensity and associated pesticide applications on fitness and enzymatic activity in reptiles-A field study.

    PubMed

    Mingo, Valentin; Lötters, Stefan; Wagner, Norman

    2017-03-01

    Environmental pollution and habitat loss are described as underlying causes for population declines in reptiles and especially affect species in agricultural landscapes. Studies dealing with effects of pesticide exposure on reptiles are limited, mainly addressing the orders Testudines and Crocodylia, but largely neglecting the most diverse reptile order Squamata (lizards and snakes). As a consequence, information regarding effects on their organisms, as well as exposure probability and pesticide uptake in the Reptilia has to be considered rather uncharted. We here ask how pesticide applications affect a widely distributed, synanthropic squamate species in Europe. We studied the common wall lizard (Podarcis muralis) with regard to enzymatic biomarkers of pesticide exposure (Glutathione-S-Transferase, Glutathione Reductase, Acetylcholinesterase) and body condition. Lizards were sampled from wild populations, along an exposure gradient (three exposed sites with differing land use intensity and one reference site). Our results suggest both dermal and oral uptake of pesticide formulations, with the former being especially relevant during the first two days after a pesticide application. Enzymatic activity slightly differed between exposure gradients, while showing overall similar patterns. Body condition of lizards decreased with increasing pesticide exposure. Furthermore, gender distribution was particularly skewed in favor to males within exposed sample sites. Although reptiles are not target organisms of pesticide applications, many species do come into contact with them, and most probably suffer from dermal and oral uptake. Thus, we believe it is indispensable for reptiles to be integrated in risk assessments in order to improve conservation practice.

  2. Role of macrofauna on benthic oxygen consumption in sandy sediments of a high-energy tidal beach

    NASA Astrophysics Data System (ADS)

    Charbonnier, Céline; Lavesque, Nicolas; Anschutz, Pierre; Bachelet, Guy; Lecroart, Pascal

    2016-06-01

    Sandy beaches exposed to tide and waves are characterized by low abundance and diversity of benthic macrofauna, because of high-energy conditions. This is the reason why there are few studies on benthic communities living in such highly dynamic environments. It has been shown recently that tidal sandy beaches may act as biogeochemical reactors. Marine organic matter that is supplied in the sand during each flood tide is efficiently mineralized through aerobic respiration. In order to quantify the role of macrofauna in the whole beach benthic respiration, we studied the macrofauna and the pore water oxygen content of an exposed sandy beach (Truc Vert, SW of France) during four seasons in 2011. The results showed that macrofauna was characterised by a low number of species of specialized organisms such as the crustaceans Eurydice naylori and Gastrosaccus spp. and the polychaetes Ophelia bicornis and Scolelepis squamata. The distribution and abundance of macrofauna were clearly affected by exposure degree and emersion time. The combined monitoring of benthic macrofauna and pore waters chemistry allowed us to estimate (1) the macrofauna oxygen uptake, calculated with a standard allometric relationship using biomass data, and (2) the total benthic oxygen uptake, calculated from the oxygen deficit measured in pore waters. This revealed that benthic macrofauna respiration represented a variable but low (<10%) contribution to the total benthic oxygen consumption. This suggests that oxygen was mainly consumed by microbial respiration.

  3. Novel parvoviruses in reptiles and genome sequence of a lizard parvovirus shed light on Dependoparvovirus genus evolution.

    PubMed

    Pénzes, Judit J; Pham, Hanh T; Benkö, Mária; Tijssen, Peter

    2015-09-01

    Here, we report the detection and partial genome characterization of two novel reptilian parvoviruses derived from a short-tailed pygmy chameleon (Rampholeon brevicaudatus) and a corn snake (Pantherophis guttatus) along with the complete genome analysis of the first lizard parvovirus, obtained from four bearded dragons (Pogona vitticeps). Both homology searches and phylogenetic tree reconstructions demonstrated that all are members of the genus Dependoparvovirus. Even though most dependoparvoviruses replicate efficiently only in co-infections with large DNA viruses, no such agents could be detected in one of the bearded dragon samples, hence the possibility of autonomous replication was explored. The alternative ORF encoding the full assembly activating protein (AAP), typical for the genus, could be obtained from reptilian parvoviruses for the first time, with a structure that appears to be more ancient than that of avian and mammalian parvoviruses. All three viruses were found to harbour short introns as previously observed for snake adeno-associated virus, shorter than that of any non-reptilian dependoparvovirus. According to the phylogenetic calculations based on full non-structural protein (Rep) and AAP sequences, the monophyletic cluster of reptilian parvoviruses seems to be the most basal out of all lineages of genus Dependoparvovirus. The suspected ability for autonomous replication, results of phylogenetic tree reconstruction, intron lengths and the structure of the AAP suggested that a single Squamata origin instead of the earlier assumed diapsid (common avian-reptilian) origin is more likely for the genus Dependoparvovirus of the family Parvoviridae.

  4. Karyotype Reorganization in the Hokou Gecko (Gekko hokouensis, Gekkonidae): The Process of Microchromosome Disappearance in Gekkota

    PubMed Central

    Srikulnath, Kornsorn; Uno, Yoshinobu; Nishida, Chizuko; Ota, Hidetoshi; Matsuda, Yoichi

    2015-01-01

    The Hokou gecko (Gekko hokouensis: Gekkonidae, Gekkota, Squamata) has the chromosome number 2n = 38, with no microchromosomes. For molecular cytogenetic characterization of the gekkotan karyotype, we constructed a cytogenetic map for G. hokouensis, which retains the ancestral karyotype of Gekkota, with 86 functional genes, and compared it with cytogenetic maps for four Toxicofera species that have many microchromosomes (Elaphe quadrivirgata, Varanus salvator macromaculatus, Leiolepis reevesii rubritaeniata, and Anolis carolinensis) and that for a lacertid species (Lacerta agilis) with only one pair of autosomal microchromosomes. Ten pairs of G. hokouensis chromosomes [GHO1, 2, 3, Z(4), 6, 7, 8, 13, 14, and 15] showed highly conserved linkage homology with macrochromosomes and/or macrochromosome arms of the four Toxicofera species and corresponded to eight L. agilis macrochromosomes (LAG). However, GHO5, GHO9, GHO10, GHO11, and LAG6 were composed of chromosome segments that have a homology with Toxicofera microchromosomes, and no homology was found in the chromosomes between G. hokouensis and L. agilis. These results suggest that repeated fusions of microchromosomes may have occurred independently in each lineage of Gekkota and Lacertidae, leading to the disappearance of microchromosomes and appearance of small-sized macrochromosomes. PMID:26241471

  5. Diversification in the Mexican horned lizard Phrynosoma orbiculare across a dynamic landscape.

    PubMed

    Bryson, Robert W; García-Vázquez, Uri Omar; Riddle, Brett R

    2012-01-01

    The widespread montane Mexican horned lizard Phrynosoma orbiculare (Squamata: Phrynosomatidae) represents an ideal species to investigate the relative impacts of Neogene vicariance and Quaternary climate change on lineage diversification across the Mexican highlands. We used mitochondrial DNA to examine the maternal history of P. orbiculare and estimate the timing and tempo of lineage diversification. Based on our results, we inferred 11 geographically structured, well supported mitochondrial lineages within this species, suggesting P. orbiculare represents a species complex. Six divergences between lineages likely occurred during the Late Miocene and Pliocene, and four splits probably happened during the Pleistocene. Diversification rate appeared relatively constant through time. Spatial and temporal divergences between lineages of P. orbiculare and co-distributed taxa suggest that a distinct period of uplifting of the Transvolcanic Belt around 7.5-3 million years ago broadly impacted diversification in taxa associated with this mountain range. To the north, several river drainages acting as filter barriers differentially subdivided co-distributed highland taxa through time. Diversification patterns observed in P. orbiculare provide additional insight into the mechanisms that impacted differentiation of highland taxa across the complex Mexican highlands.

  6. Antimicrobial Peptides in Reptiles

    PubMed Central

    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

  7. Helminth parasites of the lesser great cormorant Phalacrocorax carbo sinensis from two nesting regions in the Czech Republic.

    PubMed

    Moravec, Frantisek; Scholz, Tomas

    2016-06-13

    Parasitological examinations of 102 specimens of the lesser great cormorant Phalacrocorax carbo sinensis (Blumenbach) from two nesting regions in the Czech Republic (South Bohemia and South Moravia) were carried out at the Institute of Parasitology, Czech Academy of Sciences (previously the Czechoslovak Academy of Sciences) in the years 1987-1992. In them, a total of 19 species of helminth parasites was found, including Trematoda (11 species), Cestoda (2), Nematoda (4) and Acanthocephala (2), which can be divided into three main groups regarding their host specificity: parasites specific for cormorants (Phalacrocorax spp.) (37%), those parasitic mainly in cormorants (16%) and non-specific parasites (47%). Of the 19 species recorded, 100% were found in South Moravia, but only 47% of these 19 species in South Bohemia. The higher number of helminth species in cormorants from South Moravia and a higher proportion of non-specific species may be associated with the presence of the large Nové Mlýny water reservoir, in addition to better ecological and environmental conditions in this warmer region. Scanning electron microscopical examination of three common nematode species parasitising cormorants, Contracaecum rudolphii Hartwich, 1964, Desmidocercella incognita Solonitsin, 1932 and Syncuaria squamata (von Linstow, 1883), revealed some taxonomically important, previously unreported morphological features, such as the cephalic structures, numbers and distribution of male caudal papillae or the shapes of spicules.

  8. Helminth parasitism in the Neotropical cormorant, Phalacrocorax brasilianus, in southern Brazil: effect of host size, weight, sex, and maturity state.

    PubMed

    Monteiro, Cassandra M; Amato, José F R; Amato, Suzana B

    2011-09-01

    Forty-seven specimens of Neotropical cormorants, Phalacrocorax brasilianus, from Lago Guaíba, Guaíba, State of Rio Grande do Sul, Brazil (30° 00' S, 51°15' W), were examined for helminth parasites between 1999 and 2003. Twenty species of helminth parasites were found: ten digeneans: Austrodiplostomum mordax, Austrodiplostomum compactum, Clinostomum sp., Drepanocephalus olivaceus, Drepanocephalus spathans, Hysteromorpha triloba, Ignavia olivacei, Paryphostomum segregatum, Prosthogonimus ovatus, and Ribeiroia ondatrae; one cestode: Paradilepis caballeroi; eight nematodes: Contracaecum rudolphii, Eucoleus contortus, Eustrongylides sp., Ornithocapillaria appendiculata, Syngamus sp., Syncuaria squamata, Tetrameres (Gynaecophila) sp., and one undetermined capillariid (genus and species); and one acanthocephalan: Andracantha tandemtesticulata. The length and weight of male and female birds, as well as their sexual maturity (juvenile or adult), did not show significant difference regarding the helminth fauna; the standard length did not influence the helminth parasite indices. The prevalence of I. olivacei was higher in larger birds while the intensity of infection by this digenean species was higher in females. The abundance of P. caballeroi was higher in male birds. A. mordax and H. triloba showed higher prevalence and abundance in juvenile hosts, while O. appendiculata was more abundant in juveniles. The remaining species did not have their parasite indices influenced by the host parameters studied. The present work records the richest helminth fauna for any bird of the genus Phalacrocorax and is the first study to evaluate the influence of length, weight, sex, and maturity state on parasitism.

  9. Characterization of pituitary growth hormone and its receptor in the green iguana (Iguana iguana).

    PubMed

    Ávila-Mendoza, José; Carranza, Martha; Pérez-Rueda, Ernesto; Luna, Maricela; Arámburo, Carlos

    2014-07-01

    Pituitary growth hormone (GH) has been studied in most vertebrate groups; however, only a few studies have been carried out in reptiles. Little is known about pituitary hormones in the order Squamata, to which the green iguana (gi) belongs. In this work, we characterized the hypophysis of Iguana iguana morphologically. The somatotrophs (round cells of 7.6-10 μm containing 250- to 300-nm secretory granules where the giGH is stored) were found, by immunohistochemistry and in situ hybridization, exclusively in the caudal lobe of the pars distalis, whereas the lactotrophs were distributed only in the rostral lobe. A pituitary giGH-like protein was obtained by immuno-affinity chromatography employing a heterologous antibody against chicken GH. giGH showed molecular heterogeneity (22, 44, and 88 kDa by SDS-PAGE/Western blot under non-reducing conditions and at least four charge variants (pIs 6.2, 6.5, 6.9, 7.4) by isoelectric focusing. The pituitary giGH cDNA (1016 bp), amplified by PCR and RACE, encodes a pre-hormone of 218 aa, of which 190 aa correspond to the mature protein and 28 aa to the signal peptide. The giGH receptor cDNA was also partially sequenced. Phylogenetic analyses of the amino acid sequences of giGH and giGHR homologs in vertebrates suggest a parallel evolution and functional relationship between the GH and its receptor.

  10. Identification of echinoderms (Echinodermata) from an anchialine cave in Cozumel Island, Mexico, using DNA barcodes.

    PubMed

    Bribiesca-Contreras, Guadalupe; Solís-Marín, Francisco A; Laguarda-Figueras, Alfredo; Zaldívar-Riverón, Alejandro

    2013-11-01

    The echinoderm species richness of the Aerolito de Paraiso anchialine cave, on Cozumel Island, in the Mexican Caribbean, is assessed on the basis of morphological and DNA barcoding data. We included specimens from this cave system and from different open sea areas, and employed two different approaches for species delineation based on DNA barcoding data: a 2% cox1 divergence and the general mixed Yule-coalescent (GMYC) approaches. We subsequently compared the results derived from these approaches with our morphospecies discrimination. A total of 188 cox1 sequences belonging to specimens of four echinoderm classes were examined. The 2% cox1 divergence and GMYC approaches recovered 78 and 70 putative species, respectively, 24 and 22 of which corresponded to specimens from the anchialine system. Of 26 echinoderm species identified in the cave system, seven appear to be endemic to it. Among these are Copidaster carvenicola Solís-Marín & Laguarda-Figueras, 2010, two morphologically distinctive, undescribed species belonging to Asterinides and Ophionereis and four probably cryptic undescribed species originally assigned to Amphipholis squamata (Delle Chiaje, 1839), Astropecten duplicatus Gray, 1840, Copidaster lymani (AH Clark, 1948) and Ophiothrix angulata (Say, 1825). Further research and protection of this particularly fragile ecosystem becomes urgent because construction of tourism developments is planned nearby.

  11. Tribological analysis of the ventral scale structure in a Python regius in relation to laser textured surfaces

    NASA Astrophysics Data System (ADS)

    Abdel-Aal, H. A.; El Mansori, M.

    2013-09-01

    Laser texturing is one of the leading technologies applied to modify surface topography. To date, however, a standardized procedure to generate deterministic textures is virtually non-existent. In nature, especially in squamata, there are many examples of deterministic structured textures that allow species to control friction and condition their tribological response for efficient function. In this work, we draw a comparison between industrial surfaces and reptilian surfaces. We chose the Python regius species as a bio-analogue with a deterministic surface. We first study the structural make up of the ventral scales of the snake (both construction and metrology). We further compare the metrological features of the ventral scales to experimentally recommended performance indicators of industrial surfaces extracted from open literature. The results indicate the feasibility of engineering a laser textured surface based on the reptilian ornamentation constructs. It is shown that the metrological features, key to efficient function of a rubbing deterministic surface, are already optimized in the reptile. We further show that optimization in reptilian surfaces is based on synchronizing surface form, textures and aspects to condition the frictional response. Mimicking reptilian surfaces, we argue, may form a design methodology potentially capable of generating advanced deterministic surface constructs capable of efficient tribological function.

  12. Northern Bobwhite (Colinus virginianus) Mitochondrial Population Genomics Reveals Structure, Divergence, and Evidence for Heteroplasmy.

    PubMed

    Halley, Yvette A; Oldeschulte, David L; Bhattarai, Eric K; Hill, Joshua; Metz, Richard P; Johnson, Charles D; Presley, Steven M; Ruzicka, Rebekah E; Rollins, Dale; Peterson, Markus J; Murphy, William J; Seabury, Christopher M

    2015-01-01

    squamata) as being explanatory factors for the two bobwhite maternal lineages observed. Instead, our analyses support the supposition that two diverged maternal lineages have survived from pre-expansion to post-expansion population(s), with the segregation of some slightly deleterious nonsynonymous mutations.

  13. Effects of luteectomy in early pregnancy on the maintenance of gestation and plasma progesterone concentrations in the viviparous temperate lizard Barisia imbricata imbricata

    PubMed Central

    2010-01-01

    Background Several studies have shown that the corpus luteum is the principal source of progesterone during the gravidity period in reptiles; however, its participation in the maintenance of gestation in the viviparous squamata is in dispute. The effects of ovariectomy or luteectomy vary according to the species and the time at which the procedure is performed. In this paper, we describe the effects of luteectomy during early pregnancy on the maintenance of gestation and progesterone concentrations in the temperate Mexican viviparous lizard Barisia imbricata imbricata. Methods Twenty-four lizards were subjected to three different treatments: luteectomy, sham luteectomy or non-surgical treatment, and blood samples were obtained before and after surgical treatment at different stages of gestation to determine the effects of luteectomy on the maintenance of gestation and progesterone concentrations. Results Spontaneous abortion was not observed in any of the females. However, luteectomy provoked abnormal parturition and a significant reduction in the number of young born alive. Parturition was normal in untreated females as well as those submitted to sham luteectomy. The surgical treatment also caused a significant reduction in progesterone concentrations in luteectomised females during early and middle gestation. However, no significant differences in hormone concentrations were observed among the three groups during late gestation or immediately post-parturition. Conclusions Our observations indicate that the presence of the corpus luteum is not necesary for the maintenance of gestation, but that it does participate in parturition control. Moreover, the corpus luteum of the viviparous lizard B. i. imbricata produces progesterone, at least during the first half of pregnancy, and that an extra-ovarian source of progesterone must maintain gestation in the absence of luteal tissue. PMID:20184772

  14. Prey type and foraging ecology of Sanderlings Calidris alba in different climate zones: are tropical areas more favourable than temperate sites?

    PubMed Central

    Ntiamoa-Baidu, Yaa; Piersma, Theunis; Reneerkens, Jeroen

    2015-01-01

    Sanderlings (Calidris alba) are long-distance migratory shorebirds with a non-breeding range that spans temperate and tropical coastal habitats. Breeding in the High Arctic combined with non-breeding seasons in the tropics necessitate long migrations, which are energetically demanding. On an annual basis, the higher energy expenditures during migration might pay off if food availability in the tropics is higher than at temperate latitudes. We compared foraging behaviour of birds at a north temperate and a tropical non-breeding site in the Netherlands and Ghana, respectively. In both cases the birds used similar habitats (open beaches), and experienced similar periods of daylight, which enabled us to compare food abundance and availability, and behavioural time budgets and food intake. During the non-breeding season, Sanderlings in the Netherlands spent 79% of their day foraging; in Ghana birds spent only 38% of the daytime period foraging and the largest proportion of their time resting (58%). The main prey item in the Netherlands was the soft-bodied polychaete Scolelepis squamata, while Sanderlings in Ghana fed almost exclusively on the bivalve Donax pulchellus, which they swallowed whole and crushed internally. Average availability of polychaete worms in the Netherlands was 7.4 g ash free dry mass (AFDM) m−2, which was one tenth of the 77.1 g AFDM m−2 estimated for the beach in Ghana. In the tropical environment of Ghana the Sanderlings combined relatively low energy requirements with high prey intake rates (1.64 mg opposed to 0.13 mg AFDM s−1 for Ghana and the Netherlands respectively). Although this may suggest that the Ghana beaches are the most favourable environment, processing the hard-shelled bivalve (D. pulchellus) which is the staple food could be costly. The large amount of daytime spent resting in Ghana may be indicative of the time needed to process the shell fragments, rather than indicate rest. PMID:26290790

  15. First Large-Scale DNA Barcoding Assessment of Reptiles in the Biodiversity Hotspot of Madagascar, Based on Newly Designed COI Primers

    PubMed Central

    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

  16. Impact of a major cyclone on a southeast African estuarine lake system

    NASA Astrophysics Data System (ADS)

    Forbes, A. T.; Cyrus, D. P.

    The St Lucia lake and estuarine system in northern Natal, South Africa was struck by Cyclone Domoina on 31 January 1984. This is the only cyclone known to have traversed part of South Africa. The ensuing flood levels in the St Lucia system (which have been exceeded perhaps only one other time in recorded history) provided an opportunity to assess the effect of a major disturbance on a subtropical estuarine system. Major geomorphological changes occurred in the mouth area where all man-made structures were obliterated. The two river channels were scoured from 2-3 m to 10-14 m in depth and widened by up to 300 m, while the shoreline between the two channels retreated in places up to 100 m. An estimated 16∗10 6 m 3 of sediment were removed from the lower reaches of the system including areas of mangrove and Phragmites australis swamp. One-metre tall mangrove saplings died following inundation lasting days to weeks. Effects on the fauna included redistribution of the tanaid Apseudes digitalis, the mysid Mesopodopsis africana, the copepod Pseudodiaptomus stuhlmanni, the polychaete Scololepis squamata and the bivalve Solen cylindraceus, all typical lake species which appeared in the tidal channel linking the lake with the sea. Responses of other species such as the penaeid prawns, the crab Scylla serrata and the sole Solea bleekeri suggested that physiological tolerance, extended larval or juvenile recruitment periods and prey switching minimized long-term flood effects. No large-scale mortalities were noted, and the absence of a temperature shock is considered to be a significant feature.

  17. XROMM analysis of rib kinematics during lung ventilation in the green iguana, Iguana iguana.

    PubMed

    Brainerd, Elizabeth L; Moritz, Sabine; Ritter, Dale A

    2016-02-01

    The three-dimensional rotations of ribs during breathing are typically described as bucket-handle rotation about a dorsoventrally oriented axis, pump-handle rotation about a mediolateral axis, and caliper rotation about a rostrocaudal axis. In amniotes with double-headed ribs, rib motion is constrained primarily to one degree-of-freedom (DOF) rotation about an axis connecting the two rib articulations. However, in Squamata, the ribs are single headed and the hemispherical costovertebral joints permit rotations with three DOF. In this study, we used X-ray reconstruction of moving morphology (XROMM ) to quantify rib rotation during deep breathing in four green iguanas. We found that rib rotation was strongly dominated by bucket-handle rotation, thus exhibiting nearly hinge-like motion, despite the potential for more complex motions. The vertebral and sternal segments of each rib did not deform measurably during breathing, but they did move relative to each other at a thin, cartilaginous intracostal joint. While standing still and breathing deeply, four individual iguanas showed variability in their rib postures, with two breathing around a highly inflated posture, and two breathing around a posture with the ribs folded halfway back. Bucket-handle rotations showed clear rostrocaudal gradients, with rotation increasing from the third cervical to the first or second dorsal rib, and then decreasing again caudally, a pattern that is consistent with the intercostal muscles in the rostral intercostal spaces being the primary drivers of inspiration. The constrained, primarily bucket-handle rotations observed here during breathing do not help to explain the evolution of permissive, hemispherical costovertebral joints in squamates from the more constrained, double-headed rib articulations of other amniotes.

  18. Phylogeography of the prehensile-tailed skink Corucia zebrata on the Solomon Archipelago

    PubMed Central

    Hagen, Ingerid J; Donnellan, Stephen C; Bull, C Michael

    2012-01-01

    The biogeography of islands is often strongly influenced by prior geological events. Corucia zebrata (Squamata: Scincidae) is endemic to the geologically complex Solomon Archipelago in Northern Melanesia. We examined the level of divergence for different island populations of C. zebrata and discussed these patterns in light of Pleistocene land bridges, island isolation, and island age. Corucia zebrata was sampled from 14 locations across the Solomon Archipelago and sequenced at two mitochondrial genes (ND2 and ND4; 1697 bp in total) and four nuclear loci (rhodopsin, an unknown intron, AKAP9, and PTPN12). Measures of genetic divergence, analyses of genetic variation, and Bayesian phylogenetic inference were used and the data assessed in light of geological information. Populations of C. zebrata on separate islands were found to be genetically different from each other, with reciprocal monophyly on mitochondrial DNA. Populations on islands previously connected by Pleistocene land bridges were marginally less divergent from each other than from populations on other nearby but isolated islands. There are indications that C. zebrata has radiated across the eastern islands of the archipelago within the last 1–4 million years. Nuclear loci were not sufficiently informative to yield further information about the phylogeography of C. zebrata on the Solomon Archipelago. Analyses of the mitochondrial data suggest that dispersal between islands has been very limited and that there are barriers to gene flow within the major islands. Islands that have been isolated during the Pleistocene glacial cycles are somewhat divergent in their mitochondrial genotypes, however, isolation by distance (IBD) and recent colonization of isolated but geologically younger islands appear to have had stronger effects on the phylogeography of C. zebrata than the Pleistocene glacial cycles. This contrasts with patterns reported for avian taxa, and highlights the fact that biogeographic regions for

  19. Understanding interaction effects of climate change and fire management on bird distributions through combined process and habitat models.

    PubMed

    White, Joseph D; Gutzwiller, Kevin J; Barrow, Wylie C; Johnson-Randall, Lori; Zygo, Lisa; Swint, Pamela

    2011-06-01

    Avian conservation efforts must account for changes in vegetation composition and structure associated with climate change. We modeled vegetation change and the probability of occurrence of birds to project changes in winter bird distributions associated with climate change and fire management in the northern Chihuahuan Desert (southwestern U.S.A.). We simulated vegetation change in a process-based model (Landscape and Fire Simulator) in which anticipated climate change was associated with doubling of current atmospheric carbon dioxide over the next 50 years. We estimated the relative probability of bird occurrence on the basis of statistical models derived from field observations of birds and data on vegetation type, topography, and roads. We selected 3 focal species, Scaled Quail (Callipepla squamata), Loggerhead Shrike (Lanius ludovicianus), and Rock Wren (Salpinctes obsoletus), that had a range of probabilities of occurrence for our study area. Our simulations projected increases in relative probability of bird occurrence in shrubland and decreases in grassland and Yucca spp. and ocotillo (Fouquieria splendens) vegetation. Generally, the relative probability of occurrence of all 3 species was highest in shrubland because leaf-area index values were lower in shrubland. This high probability of occurrence likely is related to the species' use of open vegetation for foraging. Fire suppression had little effect on projected vegetation composition because as climate changed there was less fuel and burned area. Our results show that if future water limits on plant type are considered, models that incorporate spatial data may suggest how and where different species of birds may respond to vegetation changes.

  20. Morphology, cytochemical staining, and ultrastructural characteristics of the blood cells of the giant lizard of El Hierro (Gallotia simonyi).

    PubMed

    Martínez-Silvestre, A; Marco, I; Rodriguez-Dominguez, M A; Lavín, S; Cuenca, R

    2005-04-01

    The object of this study was to examine the erythrocytes, leukocytes and thrombocytes of the giant lizard of El Hierro (Gallotia simonyi) by light and electron (TEM) microscopy, and cytochemical staining. Smears were prepared from blood from the ventral coccygeal vein of 10 healthy adult lizards (five males and five females) from the Giant Lizard of El Hierro Reproduction and Research Centre, Canary Islands, Spain. The cytochemical stains used were: benzidine peroxidase (BP), chloroacetate esterase (CAE), alpha-naphthyl acetate esterase (ANAE), acid phosphatase (AP), periodic acid-Schiff (PAS), toluidine blue (TB) and May-Grünwald-Giemsa (MGG). Electron microscopy was also performed on all samples. Heterophils had granules that were heterogeneous in both size and electron density, and stained with BP, PAS and ANAE. Eosinophil granules were homogeneously electron-dense and stained for AP, CAE and ANAE. Basophils had both highly and moderately electron-dense granules, and stained with TB and ANAE. Azurophil granules were of low electron-density and stained for AP, CAE and ANAE. Azurophil cytoplasm was vacuolated on TEM. The cytoplasm of lymphocytes contained many ribosomes and was positive for AP. Monocytes had a large nucleus and a vacuolated cytoplasm but did not stain by any of the cytochemical methods used. Thrombocytes had a relatively large nucleus but little cytoplasm; they did not stain cytochemically. The blood cells of the giant lizards of El Hierro differ from those of other members of the Order Squamata both morphologically and cytochemically. The variation in cytochemical responses in the blood of reptiles makes it necessary to study species individually if meaningful clinical decisions are to be made.

  1. Molecular characterization of the leopard gecko POMC gene and expressional change in the testis by acclimation to low temperature and with a short photoperiod.

    PubMed

    Endo, Daisuke; Park, Min Kyun

    2004-08-01

    The gene for proopiomelanocortin (POMC), a common precursor of malanotropins, corticotropin, and beta-endorphin, was isolated and analyzed in the squamata species, the leopard gecko, Eublepharis macularius. Leopard gecko POMC (lgPOMC) cDNA is composed of 1299bp, excluding the poly(A) tail, and encodes 270 amino acids. The deduced amino acid sequence showed the same structural organization as that of other species and displayed identity with those of other vertebrates: 68% with mud turtles, 57/57% with African clawed frog A/B, 53% with chickens, and 45% with mice. In a phylogenic tree, the lgPOMC clustered with the sequences of the mud turtle POMC and python POMC. The lgPOMC gene comprises three exons and two introns and this structure is consistent with humans, rats, mice, African clawed frog and zebrafish. RT-PCR analysis revealed that the lgPOMC mRNA was expressed only in the whole brain, pituitary, and gonads. To analyze in more detail, a competitive assay system to quantify the expression levels of POMC mRNA was established. We measured the POMC mRNA expression levels in the leopard gecko testes following transfer from a condition of 29 degrees C, 16L/8D to 18 degrees C, 10L/14D over 6 weeks. This 6-week acclimation increased the POMC mRNA expression levels significantly. This suggests that the leopard gecko POMC-derived peptides play a role in the mediation of the effect of environmental factors on reproduction.

  2. Understanding interaction effects of climate change and fire management on bird distributions through combined process and habitat models

    USGS Publications Warehouse

    White, Joseph D.; Gutzwiller, Kevin J.; Barrow, Wylie C.; Johnson-Randall, Lori; Zygo, Lisa; Swint, Pamela

    2011-01-01

    Avian conservation efforts must account for changes in vegetation composition and structure associated with climate change. We modeled vegetation change and the probability of occurrence of birds to project changes in winter bird distributions associated with climate change and fire management in the northern Chihuahuan Desert (southwestern U.S.A.). We simulated vegetation change in a process-based model (Landscape and Fire Simulator) in which anticipated climate change was associated with doubling of current atmospheric carbon dioxide over the next 50 years. We estimated the relative probability of bird occurrence on the basis of statistical models derived from field observations of birds and data on vegetation type, topography, and roads. We selected 3 focal species, Scaled Quail (Callipepla squamata), Loggerhead Shrike (Lanius ludovicianus), and Rock Wren (Salpinctes obsoletus), that had a range of probabilities of occurrence for our study area. Our simulations projected increases in relative probability of bird occurrence in shrubland and decreases in grassland and Yucca spp. and ocotillo (Fouquieria splendens) vegetation. Generally, the relative probability of occurrence of all 3 species was highest in shrubland because leaf-area index values were lower in shrubland. This high probability of occurrence likely is related to the species' use of open vegetation for foraging. Fire suppression had little effect on projected vegetation composition because as climate changed there was less fuel and burned area. Our results show that if future water limits on plant type are considered, models that incorporate spatial data may suggest how and where different species of birds may respond to vegetation changes.

  3. Understanding interaction effects of climate change and fire management on bird distributions through combined process and habitat models

    USGS Publications Warehouse

    White, Joseph D.; Gutzwiller, Kevin J.; Barrow, Wylie C.; Johnson-Randall, Lori; Zygo, Lisa; Swint, Pamela

    2011-01-01

    Avian conservation efforts must account for changes in vegetation composition and structure associated with climate change. We modeled vegetation change and the probability of occurrence of birds to project changes in winter bird distributions associated with climate change and fire management in the northern Chihuahuan Desert (southwestern U.S.A.). We simulated vegetation change in a process-based model (Landscape and Fire Simulator) in which anticipated climate change was associated with doubling of current atmospheric carbon dioxide over the next 50 years. We estimated the relative probability of bird occurrence on the basis of statistical models derived from field observations of birds and data on vegetation type, topography, and roads. We selected 3 focal species, Scaled Quail (Callipepla squamata), Loggerhead Shrike (Lanius ludovicianus), and Rock Wren (Salpinctes obsoletus), that had a range of probabilities of occurrence for our study area. Our simulations projected increases in relative probability of bird occurrence in shrubland and decreases in grassland and Yucca spp. and ocotillo (Fouquieria splendens) vegetation. Generally, the relative probability of occurrence of all 3 species was highest in shrubland because leaf-area index values were lower in shrubland. This high probability of occurrence likely is related to the species' use of open vegetation for foraging. Fire suppression had little effect on projected vegetation composition because as climate changed there was less fuel and burned area. Our results show that if future water limits on plant type are considered, models that incorporate spatial data may suggest how and where different species of birds may respond to vegetation changes. ??2011 Society for Conservation Biology.

  4. Inference of the Protokaryotypes of Amniotes and Tetrapods and the Evolutionary Processes of Microchromosomes from Comparative Gene Mapping

    PubMed Central

    Uno, Yoshinobu; Nishida, Chizuko; Tarui, Hiroshi; Ishishita, Satoshi; Takagi, Chiyo; Nishimura, Osamu; Ishijima, Junko; Ota, Hidetoshi; Kosaka, Ayumi; Matsubara, Kazumi; Murakami, Yasunori; Kuratani, Shigeru; Ueno, Naoto; Agata, Kiyokazu; Matsuda, Yoichi

    2012-01-01

    Comparative genome analysis of non-avian reptiles and amphibians provides important clues about the process of genome evolution in tetrapods. However, there is still only limited information available on the genome structures of these organisms. Consequently, the protokaryotypes of amniotes and tetrapods and the evolutionary processes of microchromosomes in tetrapods remain poorly understood. We constructed chromosome maps of functional genes for the Chinese soft-shelled turtle (Pelodiscus sinensis), the Siamese crocodile (Crocodylus siamensis), and the Western clawed frog (Xenopus tropicalis) and compared them with genome and/or chromosome maps of other tetrapod species (salamander, lizard, snake, chicken, and human). This is the first report on the protokaryotypes of amniotes and tetrapods and the evolutionary processes of microchromosomes inferred from comparative genomic analysis of vertebrates, which cover all major non-avian reptilian taxa (Squamata, Crocodilia, Testudines). The eight largest macrochromosomes of the turtle and chicken were equivalent, and 11 linkage groups had also remained intact in the crocodile. Linkage groups of the chicken macrochromosomes were also highly conserved in X. tropicalis, two squamates, and the salamander, but not in human. Chicken microchromosomal linkages were conserved in the squamates, which have fewer microchromosomes than chicken, and also in Xenopus and the salamander, which both lack microchromosomes; in the latter, the chicken microchromosomal segments have been integrated into macrochromosomes. Our present findings open up the possibility that the ancestral amniotes and tetrapods had at least 10 large genetic linkage groups and many microchromosomes, which corresponded to the chicken macro- and microchromosomes, respectively. The turtle and chicken might retain the microchromosomes of the amniote protokaryotype almost intact. The decrease in number and/or disappearance of microchromosomes by repeated chromosomal

  5. Response of benthic macrofauna to an oil pollution: Lessons from the “Prestige” oil spill on the rocky shore of Guéthary (south of the Bay of Biscay, France)

    NASA Astrophysics Data System (ADS)

    Castège, Iker; Milon, Emilie; Pautrizel, Françoise

    2014-08-01

    The benthic community on the rocky foreshore of Guéthary (France) has been monitored since 2002. The standardized and quantitative monitoring method counts 20 geographically referenced quadrats spread on three littoral zones: upper mediolittoral, lower mediolittoral and infralittoral zones. The setting up of this monitoring occurred when the “Prestige” sunk close to the Finistere Cape in Galicia (Spain). The oil slick following the shipwreck impacted the Guéthary foreshore in early 2003. After the “Prestige” oil spill, the taxonomic richness decreased in the studied area with a loss of 16 species - from 57 in 2002 (before the shipwreck) to 41 species in 2004. Two or 3 years later, taxonomic richness increased to a level observed prior to the oil spill. Along the years, temporal variations in community structure of benthic macrofauna are revealed by detailed analysis. Some polluo-sensitive species disappeared after 2002 and have not reappeared yet (e.g.: Hymeniacidon perlevis). Some others reappeared two or three years after the spill or even later (e.g.: Amphipholis squamata, Botryllus schlosseri, Calliostoma zizyphinum, Echinus esculentus, etc.). Noteworthy changes were found in 2004 driven by the sudden increase in abundance of grazers. The following years, these abundances went back to a stable level. The benthic community seemed to recover almost 5 years later, although a new composition of macrofauna populations was observed. In overall aspect, the complexity of the benthic ecosystem response to oil spills confirms the need of regularly updated baselines to assess the impact of pollutions and more generally to maintain marine biodiversity.

  6. Northern Bobwhite (Colinus virginianus) Mitochondrial Population Genomics Reveals Structure, Divergence, and Evidence for Heteroplasmy

    PubMed Central

    Halley, Yvette A.; Oldeschulte, David L.; Bhattarai, Eric K.; Hill, Joshua; Metz, Richard P.; Johnson, Charles D.; Presley, Steven M.; Ruzicka, Rebekah E.; Rollins, Dale; Peterson, Markus J.; Murphy, William J.; Seabury, Christopher M.

    2015-01-01

    squamata) as being explanatory factors for the two bobwhite maternal lineages observed. Instead, our analyses support the supposition that two diverged maternal lineages have survived from pre-expansion to post-expansion population(s), with the segregation of some slightly deleterious nonsynonymous mutations. PMID:26713762

  7. Predator-elicited foot shakes in wall lizards (Podarcis muralis): evidence for a pursuit-deterrent function.

    PubMed

    Font, Enrique; Carazo, Pau; Pérez i de Lanuza, Guillem; Kramer, Matthew

    2012-02-01

    Under certain circumstances, prey may inform potential predators of their unprofitability by means of pursuit-deterrent signals. The evidence for pursuit-deterrent signaling in reptiles is scant and taxonomically biased. Wall lizards, Podarcis muralis (Squamata: Lacertidae) produce several distinct types of stereotyped foot shake displays, of which one, performed in antipredator contexts, is a likely candidate for a pursuit-deterrent function. We investigated this possibility by recording the responses of lizards in the field to a slowly approaching human acting as a surrogate predator. In addition to starting and flight initiation distances, we measured the presence of foot shakes, the leg that was shaken, and the distance from the observer at which the display was performed (display distance). Of a total of 484 approaches, 109 (22.5%) elicited foot shake displays. Roughly half the lizards displayed from the location where they were first sighted, while the other half moved a short distance, then displayed. There was no left-right preference in the leg used to display, but most lizards displayed with the leg closer to the approaching predator. Juveniles and subadults had smaller flight initiation distances than adult lizards. There were no sex-related differences in starting or flight initiation distances, but females, for a given distance, were more likely to display than males. Foot shake display frequency declined abruptly at 1 m. If lizards waited until the surrogate predator was this close, they mostly fled without displaying. Our results show that antipredator foot shaking in P. muralis is consistent with expectations from pursuit-deterrent theory.

  8. Purification and characterization of islet hormones (insulin, glucagon, pancreatic, polypeptide and somatostatin) from the Burmese python, Python molurus.

    PubMed

    Conlon, J M; Secor, S M; Adrian, T E; Mynarcik, D C; Whittaker, J

    1997-08-29

    Insulin was purified from an extract of the pancreas of the Burmese python, Python molurus (Squamata:Serpentes) and its primary structure established as: A Chain: Gly-Ile-Val-Glu-Gln-Cys-Cys-Glu-Asn-Thr10-Cys-Ser-Leu-Tyr-Glu-Leu- Glu-Asn-Tyr-Cys20-Asn. B-Chain: Ala-Pro-Asn-Gln-His-Leu-Cys-Gly-Ser-His10-Leu-Val-Glu-Ala-Leu-Tyr- Leu-Val-Cys-Gly20-Asp-Arg-Gly-Phe-Tyr-Tyr-Ser-Pro-Arg-Ser30. With the exception of the conservative substitution Phe --> Tyr at position B25, those residues in human insulin that comprise the receptor-binding and those residues involved in dimer and hexamer formation are fully conserved in python insulin. Python insulin was slightly more potent (1.8-fold) than human insulin in inhibiting the binding of [125I-Tyr-A14] insulin to the soluble full-length recombinant human insulin receptor but was slightly less potent (1.5-fold) than human insulin for inhibiting binding to the secreted extracellular domain of the receptor. The primary structure of python glucagon contains only one amino acid substitution (Ser28 --> Asn) compared with turtle/duck glucagon and python somatostatin is identical to that of mammalian somatostatin-14. In contrast, python pancreatic polypeptide (Arg-Ile-Ala-Pro-Val-Phe-Pro-Gly-Lys-Asp10-Glu-Leu-Ala-Lys-Phe- Tyr20-Thr-Glu-Leu-Gln-Gln-Tyr-Leu-Asn-Ser-Ile30-Asn-Arg-Pro-Arg -Phe.NH2) contains only 35 instead of the customary 36 residues and the amino acid sequence of this peptide has been poorly conserved between reptiles and birds (18 substitutions compared with alligator and 20 substitutions compared with chicken).

  9. Gradients in precipitation and seasonality between Central and Eastern Asia (Mongolia, Northern Vietnam) during the Oligocene with implication for earlier monsoonal circulation

    NASA Astrophysics Data System (ADS)

    Boehme, Madelaine; Krings, Michael; Prieto, Jérome; Schneider, Simon

    2010-05-01

    presence of large-sized longirostrine crocodiles we found diverse ferns, including arborescent Osmundaceae and planosol paleosoils similar to those which developed today in this region. Böhme, M. 2007. Oligocene-Miocene Vertebrates from the Valley of Lakes (Central Mongolia): Morphology, phylogenetic and stratigraphic implications - 3. Herpetofauna (Anura, Squamata) and palaeoclimatic implications: preliminary results.- Annalen des Naturhistorischen Museums Wien 108A: 43-52. Böhme, M., Prieto J., Schneider, S. (submitted): Cenozoic basins of Northern Vietnam: biostratigraphy, vertebrate and invertebrate fauna.- Journal of Asian Earth Sciences. Dupont-Nivet, G., Krijgsman, W., Langereis, C.G., Abels, H. A., Dai, S. and Fang, X. 2007. Tibetan Plateau aridification linked to global cooling at the Eocene-Oligocene transition.- Nature 445, 635-638.

  10. Bone indicators of grasping hands in lizards

    PubMed Central

    2016-01-01

    Grasping is one of a few adaptive mechanisms that, in conjunction with clinging, hooking, arm swinging, adhering, and flying, allowed for incursion into the arboreal eco-space. Little research has been done that addresses grasping as an enhanced manual ability in non-mammalian tetrapods, with the exception of studies comparing the anatomy of muscle and tendon structure. Previous studies showed that grasping abilities allow exploitation for narrow branch habitats and that this adaptation has clear osteological consequences. The objective of this work is to ascertain the existence of morphometric descriptors in the hand skeleton of lizards related to grasping functionality. A morphological matrix was constructed using 51 morphometric variables in 278 specimens, from 24 genera and 13 families of Squamata. To reduce the dimensions of the dataset and to organize the original variables into a simpler system, three PCAs (Principal Component Analyses) were performed using the subsets of (1) carpal variables, (2) metacarpal variables, and (3) phalanges variables. The variables that demonstrated the most significant contributions to the construction of the PCA synthetic variables were then used in subsequent analyses. To explore which morphological variables better explain the variations in the functional setting, we ran Generalized Linear Models for the three different sets. This method allows us to model the morphology that enables a particular functional trait. Grasping was considered the only response variable, taking the value of 0 or 1, while the original variables retained by the PCAs were considered predictor variables. Our analyses yielded six variables associated with grasping abilities: two belong to the carpal bones, two belong to the metacarpals and two belong to the phalanges. Grasping in lizards can be performed with hands exhibiting at least two different independently originated combinations of bones. The first is a combination of a highly elongated centrale

  11. Bone indicators of grasping hands in lizards.

    PubMed

    Fontanarrosa, Gabriela; Abdala, Virginia

    2016-01-01

    Grasping is one of a few adaptive mechanisms that, in conjunction with clinging, hooking, arm swinging, adhering, and flying, allowed for incursion into the arboreal eco-space. Little research has been done that addresses grasping as an enhanced manual ability in non-mammalian tetrapods, with the exception of studies comparing the anatomy of muscle and tendon structure. Previous studies showed that grasping abilities allow exploitation for narrow branch habitats and that this adaptation has clear osteological consequences. The objective of this work is to ascertain the existence of morphometric descriptors in the hand skeleton of lizards related to grasping functionality. A morphological matrix was constructed using 51 morphometric variables in 278 specimens, from 24 genera and 13 families of Squamata. To reduce the dimensions of the dataset and to organize the original variables into a simpler system, three PCAs (Principal Component Analyses) were performed using the subsets of (1) carpal variables, (2) metacarpal variables, and (3) phalanges variables. The variables that demonstrated the most significant contributions to the construction of the PCA synthetic variables were then used in subsequent analyses. To explore which morphological variables better explain the variations in the functional setting, we ran Generalized Linear Models for the three different sets. This method allows us to model the morphology that enables a particular functional trait. Grasping was considered the only response variable, taking the value of 0 or 1, while the original variables retained by the PCAs were considered predictor variables. Our analyses yielded six variables associated with grasping abilities: two belong to the carpal bones, two belong to the metacarpals and two belong to the phalanges. Grasping in lizards can be performed with hands exhibiting at least two different independently originated combinations of bones. The first is a combination of a highly elongated centrale

  12. Continental shelf benthos off Otago Peninsula, New Zealand

    NASA Astrophysics Data System (ADS)

    Probert, P. Keith; Wilson, John B.

    1984-09-01

    Benthic macrofauna of the continental shelf off Otago Peninsula, south-eastern New Zealand (45°51'S, 170°52'E) was surveyed by dredge sampling during 1973-1975. Numerical classification (Canberra metric coefficient and flexible sorting) was used to produce site groups and species groups, and three major benthic communities were recognised: a shallow-water (14-25 m) fauna inhabiting well-sorted fine sand, a mid-shelf fauna (concentrated in the depth range 50-76 m) associated with sediments containing the greatest proportions of gravel and siltclay, and a predominantly sand-bottom fauna occurring mainly on the outer shelf (87-150 m). All station groups were dominated numerically by polychaetes (mean of 36·6-56% of individuals) with Mollusca (13·8-25%) or Crustacea (12·1-19·4%) the next most abundant group. The inshore sand fauna was the most distinct, characteristic elements being the trochid gastropod Antisolarium egenum, an amphipod of the genus Hippomedon and dense patches of the spionid polychaete Spiophanes bombyx. Diagnostic species of the mid-shelf mixed sediments were Lepidonotus jacksoni, Psammolyce antipoda, Lumbrineris brevicirra and Phyllamphicteis foliata (Polychaeta), Terenochiton otagoensis, Micrelenchus caelatus caelatus, Maoricolpus roseus roseus and Zegalerus tenuis (Mollusca), Ampelisca chiltoni (Amphipoda) and Amphipholis squamata (Ophiuroidea). Outer shelf sand stations were faunally less distinct, but among the more characteristic species were Euthalenessa fimbriata, Sigalion sp. and Euchone sp. (Polychaeta) and Gari stangeri (Bivalvia). Several abundant species were widely distributed among station groups, notably Nephtys macroura, Lumbrineris magalhaensis, Phyllochaetopterus socialis and Owenia fusiformis (Polychaeta) and Nucula nitidula and Tawera spissa (Bivalvia). Free-living lunulitiform Bryozoa of the genus Otionella were a characteristic component of inner and outer shelf sand faunas, and their inshore penetration probably marks

  13. Unprecedented recent warming rate and temperature variability over the east Tibetan Plateau inferred from Alpine treeline dendrochronology

    NASA Astrophysics Data System (ADS)

    Shi, Chunming; Masson-Delmotte, Valérie; Daux, Valérie; Li, Zongshan; Carré, Matthieu; Moore, John C.

    2015-09-01

    Despite instrumental records showing recent large temperature rises on the Tibetan Plateau (TP), only a few tree-ring temperature reconstructions do capture this warming trend. Here, we sampled 260 trees from seven Alpine treeline locations across the southeast TP. Standardized tree-ring width chronologies of Abies squamata and Sabina squamat were produced following Regional Curve Standardization detrending. The leading principal component of these records is well correlated with the regional summer (JJA) minimum temperature (MinT) (R2 = 0.47, P < 0.001, 1953-2009). Hence we produce a regional summer MinT reconstruction spanning the last 212 years. This reconstruction reveals a long-term persistent warming trend, starting in the 1820s, at a rate of 0.45 ± 0.09 °C/century (1820-2009). This trend is also detected since the 1820s in the Asian summer MinT reconstruction produced by the PAGES 2K project, with a very close warming rate (0.43 ± 0.08 °C/century, 1820-1989). Our record also displays an enhanced multi-decadal variability since the mid-twentieth century. The 1990s-2000s are the warmest of our whole record, due to the superposition of the gradual warming trend and decadal variability during this interval. The strongest decadal cooling occurs during the 1950s and the largest warming trend during the 1970s. The magnitude of warming from 1973 to 2003 was larger than the total warming trend from 1820s to 2009. Extreme events are also more frequent since 1950. The pattern of multi-decadal variability has similarities with the Atlantic multi-decadal oscillation, suggesting common causality. CMIP5 historical simulations fail to capture both the magnitude and timing of this multi-decadal variability. The ensemble CMIP5 average produces a steady warming trend starting in the 1970s, which only accounts for about 60 % of the observed warming trend during this period. We conclude that TP summer temperature could reflect a climate response to increased greenhouse gas

  14. Reptilian transferrins: evolution of disulphide bridges and conservation of iron-binding center.

    PubMed

    Ciuraszkiewicz, Justyna; Biczycki, Marian; Maluta, Aleksandra; Martin, Samuel; Watorek, Wiesław; Olczak, Mariusz

    2007-07-01

    known bird homologues. A partially different disulphide bridge pattern was found in the Squamata (snakes and lizards). The possibility of a unique interdomain disulphide bridge was predicted for LtrF. Differences were found in iron-binding centers from those of previously known transferrins. Substitutions were found in the iron-chelating residues of StrF and TtrF and in the synergistic anion-binding residues of NtrF. In snakes, the transferrin (PtrF, HtrF and GtrF) N-lobe "dilysine trigger" occurring in all other known transferrins was not found, which indicates a different mechanism of iron release.