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1.
Zootaxa ; 3765: 469-80, 2014 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-24870915

RESUMEN

A new species, Rhabdophis guangdongensis sp. nov., is described from the Guangdong Province, China. It can be easily distinguished from other known congeners by cyt b and c-mos sequences, and by the following combination of morphological characters: body size small; head distinct from the neck; 20 maxillary teeth, the three most posterior teeth strongly enlarged, and not separated by diastemata from other teeth; six supralabials, the third and fourth touching the eye; seven infralabials, the first four in contact with anterior chin shields; dorsal scales in 15 rows throughout the body, weakly keeled, the outer row smooth; 126 ventrals; 39 paired subcaudals; anal scale divided; 44 pairs of narrow dorsolateral black cross-bars on body and 15 pairs on tail; body and tail with two dorsolateral longitudinal brownish-red lines, respectively with a series of white spots in cross-bars. The description of this new species brings the total number of described species of this genus to 21 and represents the tenth known Rhabdophis species in China.


Asunto(s)
Serpientes/anatomía & histología , Serpientes/clasificación , Animales , China , Demografía , Ecosistema , Filogenia , Serpientes/genética , Serpientes/fisiología , Especificidad de la Especie
2.
Mol Ecol ; 20(9): 1905-22, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21438932

RESUMEN

The impact of quaternary glaciation in eastern China on local fanua and flora has been a topic of considerable interest. We used mitochondrial DNA (mtDNA) sequence data and coalescent simulations to test two general biogeographic hypothesis related to the effects of Pleistocene climatic fluctuations for a widespread ophidian species (Gloydius brevicaudus) in eastern China and Korean Peninsula. The phylogenetic analysis revealed three major lineages, the southeast Coastal, Yangtze and North Lineages. The latter two are closely related and jointly form a continental lineage. Divergence dating and coalescent simulations indicate a Late Pliocene to Early Pleistocene divergence between lineages from the southeast coast and continental interior, followed by a mid-to-late Pleistocene divergence between lineages from the north and the middle-lower Yangtze Valley across East China, suggesting that all these lineages predated the last glacial maximum. An overlapping range between the two lineages within the continental lineage and a secondary contact associated with ecological transition zones on the margins of the North China Plain were also observed. These results show that vicariance patterns dominated the history of G. brevicaudus. Though the climatic events of the Pleistocene have had a marked effect on the historical distribution and intra-specific divergence of reptiles in China, coalescent and non-coalescent demographic analyses indicate that all lineages of G. brevicaudus seem not to have been adversely affected by glacial cycles during the Late Pleistocene, presumably because of an increase in the amount of climatically mild habitat in East Asia due to a decline in elevation and the development of monsoons since the Mid-End Pleistocene.


Asunto(s)
Viperidae/genética , Animales , Evolución Biológica , China , Cambio Climático , ADN Mitocondrial/genética , Evolución Molecular , Asia Oriental , Variación Genética , Genética de Población , Haplotipos , Filogeografía , Análisis de Secuencia de ADN
3.
Mol Phylogenet Evol ; 51(3): 438-46, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19249375

RESUMEN

We conducted phylogenetic analyses to identify the closest related living relatives of the Xizang and Sichuan hot-spring snakes (T. baileyi and T. zhaoermii) endemic to the Tibetan Plateau, using mitochondrial DNA sequences (cyt b, ND4) from eight specimens, together with sequences from 95 additional caenophidian and five henophidian genera that were downloaded from GenBank. Phylogenetic trees were obtained using Bayesian Inference and Maximum likelihood methods. Results suggest that hot-spring snakes, which are adapted to high and cold environments, were clustered in the monophyletic Xenodontinae. Xenodontinae is one of the largest subfamilies of colubrid snakes, with about 90 genera and more than 500 species known, and are primarily tropical snakes previously thought to be restricted to the New World. Our data failed to provide any evidence that the New World xenodontines diverged from Thermophis and dispersed into the New World, also failed to suggest a colonization of Asia by New World xenodontines by dispersal from the New World. An alternative plausible scenario may be that Thermophis and the New World xenodontines evolved independently in Asia and America, respectively, after the divergence of their common ancestor. The divergence of the two species in Thermophis was caused by the barrier of the Hengduan Mountains, and the speciation had almost occurred when Tibetan Plateau attained present elevation.


Asunto(s)
Colubridae/genética , Evolución Molecular , Filogenia , Animales , Teorema de Bayes , Núcleo Celular/genética , China , Colubridae/clasificación , ADN Mitocondrial/genética , Variación Genética , Genética de Población , Geografía , Funciones de Verosimilitud , Alineación de Secuencia , Análisis de Secuencia de ADN , Especificidad de la Especie
4.
Mol Phylogenet Evol ; 53(2): 509-22, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19616637

RESUMEN

The phylogenetic relationships among 12 genera of treefrogs (Family, Rhacophoridae), were investigated based on a large sequence data set, including five nuclear (brain-derived neurotrophic factor, proopiomelanocortin, recombination activating gene 1, tyrosinase, rhodopsin) and three mitochondrial (partial 12S and 16S ribosomal RNA and the complete valine t-RNA) genes. Phylogenetic analysis of the nuclear gene sequences resolved three major clades. The first group included Philautus, Pseudophilautus, Kurixalus, Gracixalus, and Theloderma moloch; Pseudophilautus and Kurixalus were sister taxa. The second group consisted of Nyctixalus and Theloderma. The third group contained Feihyla, Polypedates, Rhacophorus, and Chiromantis vittatus; Polypedates and Feihyla were sister taxa. Analyses of the nuclear and mitochondrial genes supported the following results: (1) Genus Liuixalus formed the sister group of all other rhacophorines. (2) Philautus, Theloderma, and Chiromantis were not resolved as monophyletic genera. Four groups, including Philautus ocellatus and P. hainanus, P. longchuanensis and P. gryllus, P. banaensis, and P. quyeti nested well within the genera Liuixalus, Pseudophilautus, Kurixalus, and Gracixalus, respectively. (3) Theloderma moloch and Chiromantis vittatus did not cluster with other species of Theloderma and Chiromantis, respectively. Foam nesting evolved only once, as did laying eggs in a jelly-like matrix containing some bubbles. Terrestrial direct development evolved twice in the Rhacophoridae.


Asunto(s)
Anuros/genética , Evolución Molecular , Filogenia , Reproducción/genética , Animales , Anuros/clasificación , Núcleo Celular/genética , ADN Mitocondrial/genética , Genes Mitocondriales , Análisis de Secuencia de ADN
5.
Mol Phylogenet Evol ; 48(1): 302-12, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18442928

RESUMEN

Phylogenetic relationships among representative species of the family Rhacophoridae were investigated based on 2904bp of sequences from both mitochondrial (12S rRNA, 16S rRNA, the complete t-RNA for valine), and nuclear (tyrosinase, rhodopsin) genes. Maximum parsimony, maximum likelihood, and Bayesian analyses were employed to reconstruct the phylogenetic trees. This analysis, combined with previous phylogenetic studies, serves as a framework for future work in rhacophorid systematics. The monophyly of Rhacophorus is strongly confirmed except for the species R.hainanus, which is the sister taxon to A.odontotarsus. The non-monophyly of the newly designated genus Aquixalus by Delorme et al. [Delorme, M., Dubois, A., Grosjean, S., Ohler, A., 2005. Une nouvelle classification générique et subgénérique de la tribu des Philautini (Amphibia, Anura, Ranidae, Rhacophorinae). Bull. Mens. Soc. Linn. Lyon 74, 165-171] is further confirmed. Aquixalus (Aquixalus) forms a well-supported monophyletic group within Kurixalus, whereas, Aquixalus (Gracixalus) is more closely related to species of Rhacophorus, Polypedates, and Chiromantis. Philautus as currently understood, does not form a monophyletic group. Philautus (Kirtixalus) is the sister group to the clade comprising Kurixalus and Aquixalus (Aquixalus), and more remotely related to Philautus (Philautus). Chiromantisromeri does not cluster with species of Chiromantis, and forms a basal clade to all rhacophorids save Buergeria. We propose some taxonomic changes that reflect these findings, but further revision should await more detailed studies, which include combined morphological and molecular analyses, with greater species sampling.


Asunto(s)
Anuros/clasificación , Anuros/genética , Animales , Núcleo Celular/genética , ADN Mitocondrial/genética , Evolución Molecular , Filogenia
6.
Zoolog Sci ; 24(1): 71-80, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17409719

RESUMEN

Based on partial sequences of the 12S and 16S ribosomal RNA genes, we estimated phylogenetic relationships among brown frogs of the Rana temporaria group from China. From the phylogenetic trees obtained, we propose to include Rana zhengi in the brown frogs. Monophyly of the brown frogs was not unambiguously supported, but four well-supported clades (A, B, C, and D) always emerged, although relationships among them remained unresolved. Clade A contained brown frogs with 24 chromosomes and was split into two distinct subclades (Subclade A-1: R. chensinensis and R. huanrenensis; Subclade A-2: R. dybowskii). Polytomous relationships among populations of R. chensinensis and R. huanrenensis suggested the necessity of further taxonomic assessment. Rana kunyuensis proved to be the sister group to R. amurensis, and these two species formed Clade B. Clade C was composed of R. omeimontis and R. chaochiaoensis, and Clade D included R. sauteri, which has been placed in other ranid genera. These relationships did not change after adding published data, and monophyly of Subclade A-1, A-2, and other East Asian brown frogs with 24 chromosomes (R. pirica and R. ornativentris) was ascertained, though their relationships were unresolved. Clade C, together with R. japonica and R. longicrus, also formed a monophyletic group. Brown frogs related to Clades A and C were estimated to have dispersed from continental Asia to adjacent regions through multiple events.


Asunto(s)
Cromosomas/genética , Filogenia , Ranidae/genética , Animales , Secuencia de Bases , Teorema de Bayes , China , Cartilla de ADN , ADN Mitocondrial/genética , Modelos Genéticos , Datos de Secuencia Molecular , Ranidae/clasificación , Análisis de Secuencia de ADN
7.
Mol Phylogenet Evol ; 43(1): 1-13, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17300963

RESUMEN

Phylogenetic relationships among representative species of the subfamily Raninae were investigated using approximately 2000 base pairs of DNA sequences from two mitochondrial (12S rRNA, 16S rRNA) and two nuclear (tyrosinase, rhodopsin) genes. Phylogenetic trees were reconstructed using maximum parsimony, Bayesian, and maximum likelihood analyses. Comparison between the nuclear and mitochondrial findings suggested that our final combined data has higher resolving power than the separate data sets. The tribes Stauroini and Ranini formed a sistergroup relationship, and within Ranini, ten major clades were consistently resolved among all analyses based on the final combined data, although the phylogenetic relationships among the ten clades were not well resolved. Our result refuted several previous taxonomic divisions: the genus Pseudoamolops was invalid, and the monophyly of the genera Amolops and Rana were not supported. We suggest elevating Raninae to familial status, and recognizing within the family, at least twelve genera including Staurois, Meristogenys, Clinotarsus, Amolops, Hylarana, Babina, Odorrana, Pseudorana, Rana, Lithobates, Glandirana, and Pelophylax. A broader sampling of species and data from more molecular markers are needed to confidently resolve the phylogenetic relationships among Ranidae.


Asunto(s)
Filogenia , Ranidae/clasificación , Ranidae/genética , Animales , Secuencia de Bases , Teorema de Bayes , ADN Mitocondrial/genética , Funciones de Verosimilitud , Modelos Genéticos , Datos de Secuencia Molecular , Monofenol Monooxigenasa/genética , Rodopsina/genética , Análisis de Secuencia de ADN
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