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1.
Zootaxa ; 4950(2): zootaxa.4950.2.4, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33903439

RESUMO

Gymnophthalmids are a highly diverse group of Neotropical lizards and its species richness is still in process of discovery. The incorporation of molecular evidence and a noticeable increase in taxon and geographic sampling in systematic studies has led to the description of numerous new genera and species of gymnophthalmids (particularly in Cercosaurinae) in recent years. Herein we describe a new genus and species of cercosaurine lizard with crocodile-like morphology, from the Venezuelan Guiana Shield on the basis of molecular phylogenetic and morphological evidence. Kataphraktosaurus gen. nov. can be readily distinguished from all other genera of Cercosaurinae by a unique combination of morphological characters that includes heterogeneous dorsal scalation with enlarged and strongly keeled scales forming two paravertebral rows, ventral and subcaudal scales imbricated and strongly keeled, large and symmetrical cephalic scales, absence of postmental scale, palpebral disc translucent and divided, tail slightly compressed, all digits clawed, and only six femoral pores (three at each hindlimb) inserted in a clump of small scales. This genus is described as monotypic and only contains Kataphraktosaurus ungerhamiltoni sp. nov., which is known from one specimen and diagnosed by the same set of aforementioned characters. The secretive habits of this species and the remoteness of the locality may explain its singleton situation. Following the International Union for Conservation of Nature's criteria, we categorized the new species as Data Deficient.


Assuntos
Lagartos , Rios , Distribuição Animal , Estruturas Animais , Animais , Guiana , Lagartos/classificação , Lagartos/genética , Filogenia , Venezuela
2.
Gigascience ; 7(4)2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29617771

RESUMO

Background: Advancements in portable scientific instruments provide promising avenues to expedite field work in order to understand the diverse array of organisms that inhabit our planet. Here, we tested the feasibility for in situ molecular analyses of endemic fauna using a portable laboratory fitting within a single backpack in one of the world's most imperiled biodiversity hotspots, the Ecuadorian Chocó rainforest. We used portable equipment, including the MinION nanopore sequencer (Oxford Nanopore Technologies) and the miniPCR (miniPCR), to perform DNA extraction, polymerase chain reaction amplification, and real-time DNA barcoding of reptile specimens in the field. Findings: We demonstrate that nanopore sequencing can be implemented in a remote tropical forest to quickly and accurately identify species using DNA barcoding, as we generated consensus sequences for species resolution with an accuracy of >99% in less than 24 hours after collecting specimens. The flexibility of our mobile laboratory further allowed us to generate sequence information at the Universidad Tecnológica Indoamérica in Quito for rare, endangered, and undescribed species. This includes the recently rediscovered Jambato toad, which was thought to be extinct for 28 years. Sequences generated on the MinION required as few as 30 reads to achieve high accuracy relative to Sanger sequencing, and with further multiplexing of samples, nanopore sequencing can become a cost-effective approach for rapid and portable DNA barcoding. Conclusions: Overall, we establish how mobile laboratories and nanopore sequencing can help to accelerate species identification in remote areas to aid in conservation efforts and be applied to research facilities in developing countries. This opens up possibilities for biodiversity studies by promoting local research capacity building, teaching nonspecialists and students about the environment, tackling wildlife crime, and promoting conservation via research-focused ecotourism.


Assuntos
Répteis/genética , Análise de Sequência de DNA/métodos , Animais , Biodiversidade , Equador , Nanoporos , Floresta Úmida
3.
Zootaxa ; 4136(3): 537-52, 2016 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-27395732

RESUMO

Herein we catalogue all geckos (Gekkonidae, Phyllodactylidae and Sphaerodactylidae) collected by Roberto Donoso-Barros in Venezuela between 1963 and 1964, deposited in the Universidad de Concepción in Chile. Donoso-Barros did not provide detailed descriptions of two species of Gonatodes named by him, despite both being valid species. We take the opportunity to do so and the type series of Gonatodes ligiae and G. petersi are described for the first time. We also present images in life of all species collected by Donoso-Barros in Venezuela.


Assuntos
Lagartos/anatomia & histologia , Lagartos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Chile , Ecossistema , Feminino , Lagartos/crescimento & desenvolvimento , Masculino , Tamanho do Órgão , Venezuela
4.
Zootaxa ; 3986(2): 151-72, 2015 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-26250178

RESUMO

We describe a new genus of New World direct-developing frog (Terrarana) from the northern Andes of Venezuela and adjacent Colombia. Tachiramantis gen. nov. includes three species formerly placed in the large genus Pristimantis. Molecular phylogenetic analysis of data from five nuclear and mitochondrial genes shows that Tachiramantis is not part of Pristimantis or any other named genus in its family (Craugastoridae or Strabomantidae). Morphological evidence further supports the distinctiveness of Tachiramantis, which has several aspects of skull morphology that are rare or absent in Pristimantis and synapomorphic for Tachiramantis, including frontoparietal-prootic fusion and degree of vomer development. The terminal phalanges, which narrow greatly before expanding at the tips, may represent an additional morphological synapomorphy. One species, T. prolixodiscus, also displays a fenestra between the posterior portions of the frontoparietals, a character state otherwise present in only 1 of 98 other sampled terraranan species. We use mapped ranges of most New World direct-developing frogs to show that Tachiramantis occurs in a geographic region that had been under-sampled in previous molecular studies of New World direct-developing frogs. Other under-sampled regions are identified in western Peru, Colombia, and northern Central America; these regions should provide fruitful target taxa for future phylogenetic studies.


Assuntos
Anuros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Anuros/anatomia & histologia , Anuros/genética , Anuros/crescimento & desenvolvimento , Tamanho Corporal , DNA Mitocondrial/genética , Feminino , Masculino , Tamanho do Órgão , Filogenia , América do Sul
5.
Zootaxa ; 3647: 43-62, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26295097

RESUMO

A new tuberculated Pristimantis is described from the eastern versant of the Venezuelan Andes. The new species is found in cloud forest at around 1600 masl on the eastern side of the Cordillera de Mérida. It is distinguished from other similar tuberculated species by its round, ill-defined canthus rostralis, ill-defined canthal stripe, and absence of pale spots on the groin and posterior surface of thighs. Pristimantis pleurostriatus is a poorly known species found in cloud forest on the western slopes of the Venezuelan Andes. We redescribe the species based on topotypic specimens. Pristimantis vanadisae is a polychomatic species varying dramatically in pattern; four chromotypes are described. Molecular data are presented which distinguish among tuberculated and other species of Pristimantis in the Cordillera de Merida. Molecular data also support placement of Mucubatrachus and Paramophrynella in Pristimantis.


Assuntos
Anuros/anatomia & histologia , Anuros/classificação , Distribuição Animal , Animais , Anuros/fisiologia , Feminino , Masculino , Especificidade da Espécie , Venezuela
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