Colubridae Research Articles

Phylogeny and systematics of the colubrid snake genera Liopeltis and Gongylosoma (Squamata: Colubridae) and description of a new Himalayan endemic genus and species.

The colubrid snakes of the genera Gongylosoma Fitzinger, 1843 and Liopeltis Fitzinger, 1843 are distributed across south and southeast Asia with five and eight nominate species, respectively. Despite their wide distribution, members of these genera are among some of the least-known colubrids. The two genera were considered synonymous in the past only to be separated later, and are defined on rather nebulose characters with a lack of support from molecular data. To test the monophyly of the two genera, we generated molecular data for the type species of Gongylosoma and species representing the two genera, including samples of Liopeltis rappii (Günther, 1860) from the western Himalayas. Results recovered paraphyly of Liopeltis, especially with regard to the genus Gongylosoma. Morphological data supports recognizing the western and eastern populations of L. rappii as two distinct species. The findings from our integrative taxonomic approach advocate establishing a new genus to embody Liopeltis rappii and a new allied species from the central and western Himalayas. A rediagnosis and revised classification of the genera Gongylosoma and Liopeltis is presented. The results further hint at cryptic diversity across members of the two genera, warranting scrutiny of the most widespread members of the group.

The complete mitochondrial genome and phylogenetic analysis for Rhabdophis chiwen (squamata: colubridae)

Rhabdophis chiwen is currently found so far in Sichuan Province, China, where it predominantly feeds on earthworms and firefly larvae. In this study, we sequenced and analyzed the mitochondrial genome of R. chiwen, which measured 17,646 bp in length and encompassed 37 genes along with two control regions. The base composition revealed percentages of 33.20% A, 25.94% T, 13.27% G, and 27.59% C. Phylogenetic analyses indicate that R. chiwen belongs to the family Colubridae and forms a sister branch with R. tigrinus. This study successfully obtained the first complete mitochondrial genome of R. chiwen, offering crucial genetic data for its evolutionary history and conservation.

The first lacertid and partly articulated snake from the Middle Miocene of the Devínska Kobyla Hill in Slovakia, from the type locality of the earliest known seal

I here describe lacertid and snake remains from the classic Middle Miocene (MN 6) locality Bonanza of the Devínska Kobyla Hill near Bratislava (Slovakia). The locality is famous for being a type locality of an early seal Devinophoca Koretsky & Holec, 2002. During the Middle Miocene, the area of Devínska Nová Ves was part of an archipelago in the western part of the Central Paratethys in the northern part of the Vienna basin. The fossils described here comprise an incomplete left maxilla of a lacertid lizard and an articulated portion of a vertebral column of a small colubrid snake with several ribs still attached. The maxilla is tentativelly allocated here to Lacerta Linnaeus, 1758 and is a rare instance of the occurrence of the clade Lacertidae Oppel, 1811 in this environment during the Middle Miocene. Moreover, it represents the oldest known occurence of this clade in Slovakia. Articulated snake specimens from the Cenozoic are rare and although only party articulated, the specimen from Bonanza is therefore exceptional. On the basis of vertebrae alone, determination of fossil colubrids is very difficult. The morphology of the Bonanza specimen is most similar to the extant Dolichophis Gistel, 1868, as also to other small fossil snakes assigned to ‘Coluber’ Linnaeus, 1758 when that genus was a catch-all grade taxon recognised from both Europe and North America, notably ‘Coluber’ dolnicensis Szyndlar, 1987 and ‘Coluber’ pouchetii (Rochebrune, 1880). Because the potentially closest living relative of the European Miocene ‘Coluber’ is Dolichophis, I assigned tentatively the material from Bonanza to cf. Dolichophis, rather than to the wastebasket taxon ‘Coluber’.

RETROSPECTIVE STUDY OF MORBIDITY AND MORTALITY IN A CAPTIVE POPULATION OF CRYPTOSPORIDIUM-POSITIVE LOUISIANA PINE SNAKES (PITUOPHIS RUTHVENI).

The Louisiana pine snake (Pituophis ruthveni) is a diurnal colubrid species native to Louisiana and eastern Texas whose free-ranging populations have been declining over at least the past 30 yr. The creation and maintenance of sustainable captive breeding programs of P. ruthveni to restore native populations has also provided ample opportunity for research into this species and for P. ruthveni to serve as a research model for other colubrid snakes. However, no investigation into prevalent causes of morbidity and mortality in captive populations of this species has been described. A research population of P. ruthveni was maintained at Louisiana State University (LSU) for over 4 yr due to unsuitability for breeding after testing positive for Cryptosporidium serpentis. Since arrival at LSU, the snakes were under close veterinary surveillance. Complete postmortem examinations were performed on 12 snakes that died or were euthanized. The aim of this study was to further understanding of common factors influencing morbidity and mortality in captive P. ruthveni infected with C. serpentis, by retrospectively reviewing postmortem exam findings from the 12 deceased members of the population at LSU. A predominant finding across individuals included bacterial infections, which were responsible for major illness or death in 37.5% of the animals. Fifty percent of snakes tested positive for Cryptosporidium sp. based on PCR performed from postmortem samples; it was directly implicated as cause of death or morbidity in 83.3% of positive cases. Although infectious disease represented the most common pathologic postmortem finding, several noninfectious disease processes were identified, including gout, goiter, and neoplasia. These findings mirror those of other retrospective investigations of reptile collections at various institutions and highlight the need for appropriate emphasis on the identification, treatment, and prevention of infectious disease as part of routine veterinary care.

New records of Dipsas welborni Arteaga & Batista, 2023, Gelanesaurus flavogularis (Altamirano-Benavides, Zaher, Lobo, Grazziotin, Sales-Nunes & Rodrigues, 2013), and Synophis insulomontanus Torres-Carvajal, Echevarría, Venegas, Chávez & Camper, 2015 in the Cordillera de Colán, Peru

A herpetological survey during recent expeditions to the foothills of the Cordillera de Colán in the Amazonas region of Peru resulted in new records and extensions of the geographical distribution of three poorly known species of reptiles: Dipsas welborni (family Colubridae), Gelanesaurus flavogularis (family Gymnophthalmidae), and Synophis insulomontanus (family Colubridae).

Herpetofaunal Diversity of Şanlıurfa Province (southeastern Turkey) with Comments on the Taxonomic Status of <i>Platyceps karelini</i> in Turkey

In this study, we report the amphibians and reptile species from Şanlıurfa Province. We conducted fieldwork for 60 days between 2016 – 2018 and additionally, we used the observation data from previous field excursions during the period from 2005 to 2016. A total of 53 amphibians and reptiles (six anurans, three chelonians, one amphisbaenian, twenty-one lizards, and twenty-two snake species) were reported from Şanlıurfa Province. A colubrid snake Platyceps ventromaculatus previously reported for the Turkey is misidentified P. karelini confirming that P. ventromaculatus does not occur in Turkey.

First report of a prolonged bite by a Western Whip Snake, <i>Hierophis viridiflavus carbonarius</i> (Bonaparte 1833) (Serpentes, Colubridae), resulting in pronounced local oedema

Although extensive research has been conducted on snake venoms, the effects of bites inflicted by non-front-fanged colubroid snakes remain incompletely understood, particularly for species of uncertain medical relevance. The Western Whip Snake (Hierophis viridiflavus) is a colubrid snake typically classified as non-venomous and harmless to humans. Nevertheless, old works reporting the presence of Duvernoy's glands in this species raise questions regarding its presumed lack of venom. This report presents the first case of a prolonged bite from a wild Western Whip Snake (Hierophis viridiflavus carbonarius) that occurred in Italy, and provides a detailed account of the resulting effects. The primary symptom experienced by the bitten subject was painless, marked local oedema, which subsided within 24h after the bite. The clinical manifestations observed in the current study suggest that Hierophis viridiflavus could have the potential to inflict bites that lead to mild local effects consistent with envenoming.

Phylogeography of Dolichophis Populations in the Aegean Region (Squamata: Colubridae) with Taxonomic Remarks

In this study, we investigate the phylogeographic patterns of Dolichophis species in the Aegean region, aiming to elucidate their genetic diversity and putative historical colonisation routes through mitochondrial and nuclear DNA data. Our findings revealed distinct phylogeographic patterns: D. caspius exhibited a higher level of haplotypes within two shallow mitochondrial lineages, contrasting with D. jugularis, which displayed lower genetic variability in the area. Additionally, we identified evidence showing possible human-mediated historical translocation of D. caspius populations to Karpathos from the Balkans mainland. The mitochondrial variability in D. jugularis remained relatively uniform across southwestern Anatolia and Dodecanese, except for Rhodes Island. The evidence from mitochondrial and nuclear data confirming the previously described morphological differentiation of the Rhodes snakes, and thus the name D. j. zinneri Cattaneo, 2012, described on the island, could be applied to this isolated population. This result addresses the first genetic view on the long-standing taxonomic uncertainties regarding the subspecies status of Rhodes D. jugularis. Our results also raise questions regarding possible historical hybridisations between D. caspius and D. jugularis in the Dodecanese islands, prompting the need for further investigation using extensive field studies and genomic approaches. Ultimately, the Aegean islands, particularly Kos and Rhodes, seem to be important sites for the evolution of these colubrid snakes and their historical dynamics.

A cyst-forming coccidian with large geographical range infecting forest and commensal rodents: Sarcocystis muricoelognathis sp. nov.

BackgroundThe geographic distribution and host-parasite interaction networks of Sarcocystis spp. in small mammals in eastern Asia remain incompletely known.MethodsExperimental infections, morphological and molecular characterizations were used for discrimination of a new Sarcocystis species isolated from colubrid snakes and small mammals collected in Thailand, Borneo and China.ResultsWe identified a new species, Sarcocystis muricoelognathis sp. nov., that features a relatively wide geographic distribution and infects both commensal and forest-inhabiting intermediate hosts. Sarcocystis sporocysts collected from rat snakes (Coelognathus radiatus, C. flavolineatus) in Thailand induced development of sarcocysts in experimental SD rats showing a type 10a cyst wall ultrastructure that was identical with those found in Rattus norvegicus from China and the forest rat Maxomys whiteheadi in Borneo. Its cystozoites had equal sizes in all intermediate hosts and locations, while sporocysts and cystozoites were distinct from other Sarcocystis species. Partial 28S rRNA sequences of S. muricoelognathis from M. whiteheadi were largely identical to those from R. norvegicus in China but distinct from newly sequenced Sarcocystiszuoi. The phylogeny of the nuclear 18S rRNA gene placed S. muricoelognathis within the so-called S. zuoi complex, including Sarcocystisattenuati, S. kani, S. scandentiborneensis and S. zuoi, while the latter clustered with the new species. However, the phylogeny of the ITS1-region confirmed the distinction between S. muricoelognathis and S. zuoi. Moreover, all three gene trees suggested that an isolate previously addressed as S. zuoi from Thailand (KU341120) is conspecific with S. muricoelognathis. Partial mitochondrial cox1 sequences of S. muricoelognathis were almost identical with those from other members of the group suggesting a shared, recent ancestry. Additionally, we isolated two partial 28S rRNA Sarcocystis sequences from Low’s squirrel Sundasciurus lowii that clustered with those of S. scandentiborneensis from treeshews.ConclusionsOur results provide strong evidence of broad geographic distributions of rodent-associated Sarcocystis and host shifts between commensal and forest small mammal species, even if the known host associations remain likely only snapshots of the true associations.Graphical

Serpentoviruses Exhibit Diverse Organization and ORF Composition with Evidence of Recombination.

Serpentoviruses are a subfamily of positive sense RNA viruses in the order Nidovirales, family Tobaniviridae, associated with respiratory disease in multiple clades of reptiles. While the broadest viral diversity is reported from captive pythons, other reptiles, including colubrid snakes, turtles, and lizards of captive and free-ranging origin are also known hosts. To better define serpentoviral diversity, eleven novel serpentovirus genomes were sequenced with an Illumina MiSeq and, when necessary, completed with other Sanger sequencing methods. The novel serpentoviral genomes, along with 57 other previously published serpentovirus genomes, were analyzed alongside four outgroup genomes. Genomic analyses included identifying unique genome templates for each serpentovirus clade, as well as analysis of coded protein composition, potential protein function, protein glycosylation sites, differences in phylogenetic history between open-reading frames, and recombination. Serpentoviral genomes contained diverse protein compositions. In addition to the fundamental structural spike, matrix, and nucleoprotein proteins required for virion formation, serpentovirus genomes also included 20 previously uncharacterized proteins. The uncharacterized proteins were homologous to a number of previously characterized proteins, including enzymes, transcription factors, scaffolding, viral resistance, and apoptosis-related proteins. Evidence for recombination was detected in multiple instances in genomes from both captive and free-ranging snakes. These results show serpentovirus as a diverse clade of viruses with genomes that code for a wide diversity of proteins potentially enhanced by recombination events.

Reptiles and Amphibians along the Coastal Area of the Eastern Province, Saudi Arabia

Thirty-two species of amphibians and reptiles were reported during this study, including 16 families (Ranidae, Geoemydidae, Cheloniidae, Gekkonidae, Sphaerodactylidae, Phyllodactylidae, Agamidae, Lacertidae, Scincidae, Varanidae, Trogonophidae, Boidae, Colubridae, Psammophiidae, Viperidae and Elapidae). Family Geckkonidae was represented by the highest number of species (8), followed by families Agamidae and Scincidae (four species for each). Trachylepis tessellata is reported for the first time to the herpetofauna of Saudi Arabia.

Morganella sp. infection in scent gland of corn snake (Pantherophis guttatus) - case report

The corn snake (Pantherophis guttatus) is a non-venomous snake from the Colubridae family. The pair of scent glands is indispensable in the physiology of reproduction and defense of the species. This structure is located caudal to the cloaca. It is responsible for releasing a thick material based on lipids containing pheromones that perform functions associated with animal behavior and survival. This work aims to report infection by Morganella sp. in a scent gland in a female corn snake, evidencing the diagnosis and treatment. An increase in volume was seen in the final third, proximal to the cloaca, firm consistency, immobile, and approximately 4 cm long and painful to touch. Samples of the material were collected for bacterial culture and antibiogram examination, being positive for bacteria of the genus Morganella. Based on the result of the antibiogram, it was possible to determine the most appropriate therapeutic protocol, with the referral to perform the surgical procedure to remove the tissue compromised by the infection, remaining stable until the removal of the stitches 40 days after the procedure, with total surgical wound healing.

Morphological and molecular phylogenetic characterization of Sarcocystis kani sp. nov. and other novel, closely related Sarcocystis spp. infecting small mammals and colubrid snakes in Asia

We investigated the morphology and phylogenetic relationships of novel and previously recognized Sarcocystis spp. infecting small mammals and colubrid snakes in Asia. The nuclear 18S rRNA and mitochondrial cox1 of Sarcocystis sp.1 from mangrove snakes (Boiga dendrophila) in Thailand and Sarcocystis sp.2 from a ricefield rat (Rattus argentiventer) in Sumatra were partially sequenced. Sporocysts of Sarcocystis sp.1 induced development of sarcocysts in experimentally infected rats, which showed a unique ultrastructure that was observed previously by S.P. Kan in rats from Malaysia; therefore, we describe this species as Sarcocystis kani sp. nov. Its integration into the 18S rRNA phylogeny of Sarcocystis spp. cycling between small mammals and colubrid snakes helped clarify relationships among the so-called S. zuoi-complex of molecularly cryptic species: Sarcocystis kani sp. nov., S. sp.2, S. attenuati, S. scandentiborneensis, and S. zuoi were all included in this clade. Tree topology was resolved into dichotomies congruent with the morphological disparities between the taxa. However, cox1 gene sequencing (including newly sequenced S. singaporensis and S. zamani) revealed that Sarcocystis kani, S. attenuati, and S. scandentiborneensis were identical suggesting a recent, common ancestry. To identify other distinctive features, lineage-specific molecular patterns within both genes were examined revealing that all 18S rRNA sequences of the S. zuoi – complex possess a unique, 7-nt long motif in helix 38 of domain V7 that was different in S. clethrionomyelaphis which branched off basally from the complex. Three-dimensional homology modelling of COX1 protein structure identified amino acid substitutions within the barcode area specific for the S. zuoi-complex and substantial divergence in structurally important amino acids between Sarcocystis species of snakes as definitive hosts and other lineages of the Sarcocystidae. We discuss the utility of selected genes for species delimitation of the Sarcocystis spp. under investigation, which probably evolved during recent radiations of their intermediate and definitive hosts.

A reference genome assembly for the continentally distributed ring-necked snake, Diadophis punctatus.

Snakes in the family Colubridae include more than 2,000 currently recognized species, and comprise roughly 75% of the global snake species diversity on Earth. For such a spectacular radiation, colubrid snakes remain poorly understood ecologically and genetically. Two subfamilies, Colubrinae (788 species) and Dipsadinae (833 species), comprise the bulk of colubrid species richness. Dipsadines are a speciose and diverse group of snakes that largely inhabit Central and South America, with a handful of small-body-size genera that have invaded North America. Among them, the ring-necked snake, Diadophis punctatus, has an incredibly broad distribution with 14 subspecies. Given its continental distribution and high degree of variation in coloration, diet, feeding ecology, and behavior, the ring-necked snake is an excellent species for the study of genetic diversity and trait evolution. Within California, six subspecies form a continuously distributed "ring species" around the Central Valley, while a seventh, the regal ring-necked snake, Diadophis punctatus regalis is a disjunct outlier and Species of Special Concern in the state. Here, we report a new reference genome assembly for the San Diego ring-necked snake, D. p. similis, as part of the California Conservation Genomics Project. This assembly comprises a total of 444 scaffolds spanning 1,783 Mb and has a contig N50 of 8.0 Mb, scaffold N50 of 83 Mb, and BUSCO completeness score of 94.5%. This reference genome will be a valuable resource for studies of the taxonomy, conservation, and evolution of the ring-necked snake across its broad, continental distribution.

Seasonal Reptilian Diversity at Gautala Reserve Forest, Aurangabad (Maharashtra), India.

Reptiles are playing a vital role in ecology. These reptiles show a diverse range of habitat adaptations. They are dispersed in extreme desert conditions as well as in low-temperature areas and they are broadly dispersed across the world. The occurrence of reptiles is a sign of rich biodiversity and ecology. To assess the distribution of the reptile species in a given area, a reptilian species survey was carried out in the Gautala Reserve Forest, where 15 different spots were selected during the rainy, winter, and summer seasons. A checklist was created for the period of 2017-2018. During the investigation, a total of 28 species of reptiles from 6 families were found. The transect method was used to sample direct and indirect evidence of reptilian species. This paper discusses seasonal variations in reptilian diversity and statistical analysis methods. The Boidae family has fewer species than various other families, compared to the huge number of species of the Colubridae family reported in the current study. According to the IUCN, Three species of reptiles, the Common Sand Boa (Gongylophis Conicus), India Rock Python (Python molurus molurus), and John's Sand Boa (Eryx johnii), are Near Threatened (NT- Decreasing), and one species of reptile, the Gunther's Racer (Coluber gracilis), is Data Deficient (DD-Unknown). The remaining 24 species of reptiles are considered Least Concerned. Baseline information on the resilience of these reptile species was collected for the current investigation. These details will be useful for future planning on the preservation of reptile diversity.

Keanekaragaman Subordo Serpentes Di Kawasan Pantai Sendangbiru Kabupaten Malang Provinsi Jawa Timur

The diversity of the Suborder Serpentes has an important role in the ecosystem and is used as a parameter of environmental quality. The high diversity of the Suborder Serpentes in Indonesia is not matched by adequate research and publications. The Sendangbiru beach area is a Nature Reserve area which has the potential to become a natural habitat for all types of animals, especially the Serpentes Suborder because it has a stable temperature and many unspoiled habitats. This study aims to find out what types of snakes are in the area and how the diversity, level of abundance, and dominance of the Suborder Serpentes are. This research method uses a descriptive explorative method by exploring the routes on Sendangbiru beach area. The suborder Serpentes found will be measured for morphometry, namely by measuring the snake's body which includes body length, tail length, total length, number of scales, and sex. This study found 6 species of snakes. The six species found consisted of the Aglypha, Solenoglypha, and Ophistoglypha snakes. The snake species that have been found belong to the Colubridae family as many as 4 species from 3 different genera, namely the species Dendrelaphis pictus of the genus Dendrelaphis, the species Ahaetulla nasuta and Ahaetulla prasina of the genus Ahaetulla, and the species Chrysopelea paradisi of the genus Chrysopelea. While the other 2 species are the Viperidae family with the species name Cryptelytrops albolabris, the genus Cryptelytrops, and the Pythonidae family, with the species name Malayopython reticulatus, the genus Malayopython. The diversity index (H') in the Sendangbiru beach area is 1.79 with a moderate diversity value, an evenness value (E) 1 and indicates that the suborder found on Sendangbiru beach area has an even value and stable community, and a dominance value (C ) 0.17 with a low dominance value.

Systematic Assessment of Hebius beddomei (Günther, 1864) (Serpentes: Colubridae: Natricinae) with Description of a New Genus and a New Allied Species from the Western Ghats, India

Hebius beddomei (Günther, 1864) is an endemic natricine colubrid snake species from the biodiverse Western Ghats, India. A recent molecular phylogeny provided evidence for the paraphyly of the genus Hebius, with Hebius beddomei recovered as sister to a clade containing Fowlea and Atretium. Freshly collected specimens and existing museum material allowed us to elucidate the generic status of the species and identify two distinct populations, one of which is described as a new species. A new genus, Sahyadriophis gen. nov., is proposed to accommodate Sahyadriophis beddomei gen. et. comb. nov., and Sahyadriophis uttaraghati gen. et. sp. nov. is described as a new species from the northern part of the range. The discovery of a new Oligocene divergent lineage, Sahyadriophis gen. nov., highlights the role of the Western Ghats as a source of relic lineages.

Ophidian Serpentoviruses: A Review and Perspective

Ophidian serpentoviruses, initially referred to as nidoviruses, were first documented in captive pythons nearly ten years ago. Since then, much has been learned about these important pathogens, now classified in subfamily Serpentovirinae of family Tobaniviridae and representing an important emerging pathogen that threatens captive snakes. Serpentoviral infections are best characterized in pythons (family Pythonidae), but have also been documented in boas (family Boidae) and colubrids (family Colubridae), as well as shingleback skinks (Tiliqua rugosa), veiled chameleons (Chamaeleo calyptratus), and the Bellinger River snapping turtle (Myuchelys georgesi). Clinical signs include increased oral mucous secretion, oral mucosal reddening, dyspnea, anorexia, and weight loss. Subclinical infections can also occur, and multiple studies report a lack of correlation between clinical signs and presence of serpentoviral nucleic acids in snakes. Lesions associated with serpentoviral infections predominantly occur in the upper respiratory and gastrointestinal tracts but can also extend to the lungs. Microscopically, these lesions may consist of inflammation, epithelial proliferation, and proliferative interstitial pneumonias, which can be complicated by concurrent bacterial bronchopneumonia. The most common method of diagnosis is reverse transcription PCR to detect viral RNA, and oral/choanal swabs are reliable samples for ante- or postmortem diagnosis. Specific treatment protocols have not yet been described, and management is based on supportive care. This manuscript presents a narrative review of all serpentovirus publications to date with perspective from researchers working to further characterize these pathogens, with the goal of serving as a comprehensive clinical and diagnostic overview for clinicians, zoological curatorial staff, wildlife biologists, and hobbyists.

Proliferative strongyloidiasis in a colony of colubrid snakes.

Strongyloides are small rhabditid nematodes primarily associated with enteric disease in a variety of animal species, including reptiles. Strongyloides spp life stages were associated with a disease outbreak in a large breeding colony of snakes. Multiple Pantherophis and Lampropeltis colubrids exhibited respiratory distress, anorexia, stomatitis, facial deformation, and waning body condition that resulted in death or necessitated euthanasia. Postmortem examinations of 13 snakes revealed epithelial hyperplasia and inflammation of the alimentary and respiratory tracts associated with varying numbers of adult and larval nematodes and embryonated or larvated ova. In a subset of snakes, aberrant nematode migration was also observed in the eye, genitourinary system, coelom, and vasculature. Histomorphology and gross examination of parasitic adult female nematodes from host tissues were consistent with a Strongyloides spp. Sedimented fecal material from 101/160 (63%) snakes housed in the affected facility was positive for nematodes and/or larvated ova. Polymerase chain reaction amplification and sequencing of portions of the 18S and 28S ribosomal ribonucleic acid (RNA) genes and the internal transcribed spacer region of adult female parasites and positive fecal samples supported the diagnosis of strongyloidiasis. Strongyloides spp possess a unique life cycle capable of alternating between parasitic (homogonic) and free-living (heterogonic) stages, resulting in the production of directly infective larvae. Commonly utilized husbandry practices in reptile collections can amplify the numbers of infective larvae generated in the captive environment, increasing the risk for rhabditid hyperinfections. This report documents morbidity, mortality, and non-enteric disease manifestations due to Strongyloides hyperinfections in a captive colubrid snake colony.

Description of trunk neural crest migration and peripheral nervous system formation in the Egyptian cobra Naja haje haje

The neural crest is a stem cell population that forms in the neurectoderm of all vertebrates and gives rise to a diverse set of cells such as sensory neurons, Schwann cells and melanocytes. Neural crest development in snakes is still poorly understood. From the point of view of evolutionary and comparative anatomy is an interesting topic given the unique anatomy of snakes. The aim of the study was to characterize how trunk neural crest cells (TNCC) migrate in the developing elapid snake Naja haje haje and consequently, look at the beginnings of development of neural crest derived sensory ganglia (DRG) and spinal nerves. We found that trunk neural crest and DRG development in Naja haje haje is like what has been described in other vertebrates and the colubrid snake strengthening our knowledge on the conserved mechanisms of neural crest development across species. Here we use the marker HNK1 to follow the migratory behavior of TNCC in the elapid snake Naja haje haje through stages 1–6 (1–9 days postoviposition). We observed that the TNCC of both snake species migrate through the rostral portion of the somite, a pattern also conserved in birds and mammals. The development of cobra peripheral nervous system, using neuronal and glial markers, showed the presence of spectrin in Schwann cell precursors and of axonal plexus along the length of the cobra embryos. In conclusion, cobra embryos show strong conserved patterns in TNCC and PNS development among vertebrates.