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1.
Zootaxa ; 4000(4): 401-27, 2015 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-26623733

RESUMEN

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.


Asunto(s)
Lagartos/clasificación , Filogenia , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Brasil , Ecosistema , Femenino , Lagartos/anatomía & histología , Lagartos/genética , Lagartos/crecimiento & desarrollo , Masculino , Datos de Secuencia Molecular , Tamaño de los Órganos , Terminología como Asunto
2.
Mol Phylogenet Evol ; 80: 113-24, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25109652

RESUMEN

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.


Asunto(s)
Especiación Genética , Lagartos/clasificación , Filogenia , Animales , Teorema de Bayes , Biodiversidad , Brasil , Funciones de Verosimilitud , Lagartos/genética , Modelos Genéticos , Análisis de Secuencia de ADN , Clima Tropical
3.
Zootaxa ; 3702: 459-72, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-26146739

RESUMEN

A new Crossodactylodes is described from Serra das Lontras, in the highlands of the Atlantic Forests of southern Bahia. The new species can be distinguished from all other Crossodactylodes by having Finger I ending in an acute tip, a larger body size, by cranial features, and by molecular data. Like their congeners, the new species live in bromeliads but is widely geographically disjunct, being apparently restricted to the summit of a mountain range in Northeastern Brazil.


Asunto(s)
Anuros/anatomía & histología , Anuros/clasificación , Animales , Anuros/genética , Brasil , Ecosistema , Femenino , Bosques , Masculino , Filogenia
4.
Mol Phylogenet Evol ; 62(3): 826-38, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22166838

RESUMEN

Dendrophryniscus is an early diverging clade of bufonids represented by few small-bodied species distributed in Amazonia and the Atlantic Forest. We used mitochondrial (414 bp of 12S, 575 bp of 16S genes) and nuclear DNA (785 bp of RAG-1) to investigate phylogenetic relationships and the timing of diversification within the genus. These molecular data were gathered from 23 specimens from 19 populations, including eight out of the 10 nominal species of the genus as well as Rhinella boulengeri. Analyses also included sequences of representatives of 18 other bufonid genera that were publically available. We also examined morphological characters to analyze differences within Dendrophryniscus. We found deep genetic divergence between an Amazonian and an Atlantic Forest clade, dating back to Eocene. Morphological data corroborate this distinction. We thus propose to assign the Amazonian species to a new genus, Amazonella. The species currently named R. boulengeri, which has been previously assigned to the genus Rhamphophryne, is shown to be closely related to Dendrophryniscus species. Our findings illustrate cryptic trends in bufonid morphological evolution, and point to a deep history of persistence and diversification within the Amazonian and Atlantic rainforests. We discuss our results in light of available paleoecological data and the biogeographic patterns observed in other similarly distributed groups.


Asunto(s)
Bufonidae/clasificación , Bufonidae/genética , Filogenia , Animales , Evolución Biológica , Bufonidae/anatomía & histología , ADN Mitocondrial/química , Genes RAG-1 , Genes de ARNr , Datos de Secuencia Molecular , Filogeografía
5.
Biota neotrop. (Online, Ed. port.) ; 9(1): 263-269, Jan.-Mar. 2009. graf, mapas, tab
Artículo en Inglés | LILACS | ID: lil-518451

RESUMEN

We present data on the diet of 15 species of snakes belonging to a community from Reserva Particular do Patrimônio Natural Feliciano Miguel Abdala, an Atlantic Forest fragment of Southeastern Brazil, based on their stomach contents. For 12 items we were able to determine the direction of the ingestion. Most snakes ingested the prey head-first. A cluster analysis was conducted with items grouped as chilopods, mollusks, adult anurans, anuran tadpoles, lizards, amphisbaenians, snakes, and rodents. The phylogenetic influence on diet preferences is discussed.


Apresentamos aqui a dieta de 15 espécies de serpentes de uma comunidade da Reserva Particular do Patrimônio Natural Feliciano Miguel Abdala, um fragmento de Mata Atlântica do sudeste do Brasil, com base na análise de conteúdos estomacais. Para 12 itens, pudemos determinar o sentido de ingestão da presa. A maioria das serpentes ingeriu a presa no sentido cranial-caudal. Realizamos uma análise de agrupamento reunindo os itens nas categorias quilópodes, moluscos, anuros adultos, girinos, lagartos, anfisbenas, serpentes e roedores. A influência da filogenia sobre a dieta das espécies é discutida.


Asunto(s)
Anfibios , Anuros , Biodiversidad , Conducta Alimentaria/clasificación , Larva , Moluscos , Serpientes
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