The Craugastor rhodopis Species Group includes two leaf-litter frog species (C. loki and C. rhodopis). These direct-developing frogs inhabit tropical regions of Mexico and northern Central America. Characterizing diversity within the group has been difficult due to high levels of phenotypic polymorphism within and between species. Because of these polymorphisms, each taxon has junior synonyms. Using a fragment of mitochondrial DNA (mtDNA), we investigated genetic diversity in the C. rhodopis Species Group. We then examined type specimens (including types of junior synonyms) to match nomenclature to geographically circumscribed genetic clusters. Our molecular analyses revealed four major lineages within the C. rhodopis Species Group: (1) a widely distributed clade in western Mexico, (2) a highland clade in eastern Mexico, (3) a widely distributed lowland clade occurring in eastern Mexico, Guatemala and El Salvador, and (4) a haplotype from Volcán San Martín in Veracruz, Mexico. We identified the first clade as C. occidentalis, a taxon currently placed in the ecologically similar but phylogenetically distant C. mexicanus Species Series. In light of this we place C. occidentalis in the C. rhodopis Species Group and designate a lectotype and paralectotype for the species. The second and third clades inhabiting eastern Mexico and northern Central America correspond to C. rhodopis and C. loki, respectively. Additionally, we examined the taxonomic distribution of certain colour pattern traits and compensatory mutations in Domain III of the mtDNA 12S ribosomal RNA gene. Our recovery of the divergent Veracruz haplotype and extensive mtDNA structure within species indicates that additional taxonomic revision will be necessary.

Nayarit is one of the Mexican states where less has been published regarding the fauna of amphibians. The aim of this work was to generate a list of amphibians of Nayarit through literature review and fieldwork. The amphibian fauna of Nayarit consists of 37 species, belonging to 21 genera, 10 families, and two orders. Among these 37 species, 36 are native, 21 are endemic to Mexico, and one is exotic (the American bullfrog Lithobates catesbeianus). In total, nine species are under the category of “Special Protection” and one as “Endangered” by Mexican laws and four (one as “Endangered” and three as “Vulnerable”) under international laws of protection. In the near future, our expectation is that more species will be added to the list of species of amphibians in Nayarit, as more fieldwork remains to be done in some remote and unexplored areas of the state.

Effective and targeted conservation action requires detailed information about species, their distribution, systematics and ecology as well as the distribution of threat processes which affect them. Knowledge of reptilian diversity remains surprisingly disparate, and innovative means of gaining rapid insight into the status of reptiles are needed in order to highlight urgent conservation cases and inform environmental policy with appropriate biodiversity information in a timely manner. We present the first ever global analysis of extinction risk in reptiles, based on a random representative sample of 1500 species (16% of all currently known species). To our knowledge, our results provide the first analysis of the global conservation status and distribution patterns of reptiles and the threats affecting them, highlighting conservation priorities and knowledge gaps which need to be addressed urgently to ensure the continued survival of the world’s reptiles. Nearly one in five reptilian species are threatened with extinction, with another one in five species classed as Data Deficient. The proportion of threatened reptile species is highest in freshwater environments, tropical regions and on oceanic islands, while data deficiency was highest in tropical areas, such as Central Africa and Southeast Asia, and among fossorial reptiles. Our results emphasise the need for research attention to be focussed on tropical areas which are experiencing the most dramatic rates of habitat loss, on fossorial reptiles for which there is a chronic lack of data, and on certain taxa such as snakes for which extinction risk may currently be underestimated due to lack of population information. Conservation actions specifically need to mitigate the effects of human-induced habitat loss and harvesting, which are the predominant threats to reptiles.

Mexico possesses high levels of endemic biodiversity, especially for squamate reptiles. However, the evolutionary relationships among many reptiles in this region are not well known. The closely related genera of Sonora Baird and Girard 1853 and Procinura Cope 1879 are coralsnake mimics found from the central and western United States to southwestern Mexico and Baja California. Although species delimitation in this group has historically relied upon colour pattern and other morphological characters, many populations of these species display colour pattern polymorphism, which may confound taxonomy. We used molecular phylogenetics to assess the evolutionary relationships and delimit species within Sonora, focusing on the phylogenetic position of Procinura and the validity of S. mutabilis and aequalis. We sequenced two mitochondrial (ND4 and cytb) and two nuclear (c-mos and RAG-1) genes for the single species of Procinura and each of the four species of Sonora. We analysed these sequences using maximum parsimony, maximum likelihood and Bayesian phylogenetic analyses on separately concatenated mitochondrial and nuclear datasets. Additionally, we used Bayesian coalescent methods to build a species tree (Bayesian species tree analysis) and delimit species boundaries (Bayesian species delimitation). All methods indicated that Procinura is deeply nested within Sonora, and most individual species are well supported. However, we found that one taxon (S. aequalis) is paraphyletic with regard to another (S. mutabilis). We recommend that the genus Procinura be synonymised with Sonora and that S. aequalis be synonymised with S. mutabilis. Additionally, the phylogenetic patterns that we document are broadly congruent with a Miocene or Pliocene divergence between S. michoacanensis and S. mutabilis along the Trans-Mexican Volcanic Belt. Finally, our data are consistent with the early evolution of coralsnake mimicry and colour pattern polymorphism within the genus Sonora.

A new species of Tantilla is described from a single specimen obtained from Volcan Ceboruco, southern Nayarit, Mexico. The new species closely resembles other species of the Tantilla calamarina group. With the addition of the taxon described herein, the calamarina group now contains seven species, T. calamarina, Tantilla cascadae, Tantilla coronadoi, Tantilla deppei, Tantilla sertula, Tantilla vermiformis, and the new species described herein. Collectively, members of the group are distributed along the Pacific versant of Middle America in three disjunct regions: (1) from northern Sinaloa to Guerrero, including the Tres Marias Islands; (2) the Balsas Basin of Morelos, Puebla, Distrito Federal, and the State of Mexico; and (3) from El Salvador to northwestern Costa Rica. We provide a small list of specimens collected in the highlands of Nayarit, and report Lithobates psilonota, Ambystoma rosaceum, Elgaria kingi, Plestiodon lynxe and Rhadinaea hesperia for the first time from the state. We report the second specimen of T. sertula, known previously only from the holotype.