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1.
Proc Natl Acad Sci U S A ; 120(40): e2302424120, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37748058

RESUMO

Delimiting and naming biodiversity is a vital step toward wildlife conservation and research. However, species delimitation must be consistent across biota so that the limited resources available for nature protection can be spent effectively and objectively. To date, newly discovered lineages typically are either left undescribed and thus remain unprotected or are being erroneously proposed as new species despite mixed evidence for completed speciation, in turn contributing to the emerging problem of taxonomic inflation. Inspired by recent conceptual and methodological progress, we propose a standardized workflow for species delimitation that combines phylogenetic and hybrid zone analyses of genomic datasets ("genomic taxonomy"), in which phylogeographic lineages that do not freely admix are ranked as species, while those that have remained fully genetically compatible are ranked as subspecies. In both cases, we encourage their formal taxonomic naming, diagnosis, and description to promote social awareness toward biodiversity. The use of loci throughout the genome overcomes the unreliability of widely used barcoding genes when phylogeographic patterns are complex, while the evaluation of divergence and reproductive isolation unifies the long-opposed concepts of lineage species and biological species. We suggest that a shift in conservation assessments from a single level (species) toward a two-level hierarchy (species and subspecies) will lead to a more balanced perception of biodiversity in which both intraspecific and interspecific diversity are valued and more adequately protected.


Assuntos
Biodiversidade , Biota , Animais , Filogenia , Animais Selvagens , Genômica
3.
Mol Phylogenet Evol ; 124: 162-171, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29530499

RESUMO

Southeast Asia and southern China (SEA-SC) harbor a highly diverse and endemic flora and fauna that is under increasing threat. An understanding of the biogeographical history and drivers of this diversity is lacking, especially in some of the most diverse and threatened groups. The Asian leaf-litter frog genus Leptolalax Dubois 1980 is a forest-dependent genus distributed throughout SEA-SC, making it an ideal study group to examine specific biogeographic hypotheses. In addition, the diversity of this genus remains poorly understood, and the phylogenetic relationships among species of Leptolalax and closely related Leptobrachella Smith 1928 remain unclear. Herein, we evaluate species-level diversity based on 48 of the 53 described species from throughout the distribution of Leptolalax. Molecular analyses reveal many undescribed species, mostly in southern China and Indochina. Our well-resolved phylogeny based on multiple nuclear DNA markers shows that Leptolalax is not monophyletic with respect to Leptobrachella and, thus, we assign the former to being a junior synonym of the latter. Similarly, analyses reject monophyly of the two subgenera of Leptolalax. The diversification pattern of the group is complex, involving a high degree of sympatry and prevalence of microendemic species. Northern Sundaland (Borneo) and eastern Indochina (Vietnam) appear to have played pivotal roles as geographical centers of diversification, and paleoclimatic changes and tectonic movements seem to have driven the major divergence of clades. Analyses fail to reject an "upstream" colonization hypothesis, and, thus, the genus appears to have originated in Sundaland and then colonized mainland Asia. Our results reveal that both vicariance and dispersal are responsible for current distribution patterns in the genus.


Assuntos
Anuros/classificação , Biodiversidade , Filogenia , Animais , Ásia , Sequência de Bases , Teorema de Bayes , Filogeografia , Especificidade da Espécie , Fatores de Tempo
4.
Mol Phylogenet Evol ; 106: 28-43, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27622725

RESUMO

The horned toad assemblage, genus Megophrys sensu lato, currently includes three groups previously recognized as the genera Atympanophrys, Xenophrys and Megophrys sensu stricto. The taxonomic status and species composition of the three groups remain controversial due to conflicting phenotypic analyses and insufficient phylogenetic reconstruction; likewise, the position of the monotypic Borneophrys remains uncertain with respect to the horned toads. Further, the diversity of the horned toads remains poorly understood, especially for widespread species. Herein, we evaluate species-level diversity based on 45 of the 57 described species from throughout southern China, Southeast Asia and the Himalayas using Bayesian inference trees and the Generalized Mixed Yule Coalescent (GMYC) approach. We estimate the phylogeny using both mitochondrial and nuclear DNA data. Analyses reveal statistically significant mito-nuclear discordance. All analyses resolve paraphyly for horned toads involving multiple strongly supported clades. These clades correspond with geography. We resurrect the genera Atympanophrys and Xenophrys from the synonymy of Megophrys to eliminate paraphyly of Megophrys s.l. and to account for the morphological, molecular and biogeographic differences among these groups, but we also provide an alternative option. Our study suggests that Borneophrys is junior synonym of Megophrys sensu stricto. We provide an estimation of timeframe for the horned toads. The mitochondrial and nuclear trees indicate the presence of many putative undescribed species. Widespread species, such as Xenophrys major and X. minor, likely have dramatically underestimated diversity. The integration of morphological and molecular evidence can validate this discovery. Montane forest dynamics appear to play a significant role in driving diversification of horned toads.


Assuntos
Anuros/classificação , Animais , Anuros/genética , Teorema de Bayes , Bufonidae/classificação , Bufonidae/genética , China , DNA/química , DNA/isolamento & purificação , DNA/metabolismo , DNA Mitocondrial/classificação , DNA Mitocondrial/genética , Filogenia , Filogeografia , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
5.
Syst Biol ; 65(5): 824-42, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27288482

RESUMO

True frogs of the genus Rana are widely used as model organisms in studies of development, genetics, physiology, ecology, behavior, and evolution. Comparative studies among the more than 100 species of Rana rely on an understanding of the evolutionary history and patterns of diversification of the group. We estimate a well-resolved, time-calibrated phylogeny from sequences of six nuclear and three mitochondrial loci sampled from most species of Rana, and use that phylogeny to clarify the group's diversification and global biogeography. Our analyses consistently support an "Out of Asia" pattern with two independent dispersals of Rana from East Asia to North America via Beringian land bridges. The more species-rich lineage of New World Rana appears to have experienced a rapid radiation following its colonization of the New World, especially with its expansion into montane and tropical areas of Mexico, Central America, and South America. In contrast, Old World Rana exhibit different trajectories of diversification; diversification in the Old World began very slowly and later underwent a distinct increase in speciation rate around 29-18 Ma. Net diversification is associated with environmental changes and especially intensive tectonic movements along the Asian margin from the Oligocene to early Miocene. Our phylogeny further suggests that previous classifications were misled by morphological homoplasy and plesiomorphic color patterns, as well as a reliance primarily on mitochondrial genes. We provide a phylogenetic taxonomy based on analyses of multiple nuclear and mitochondrial gene loci. [Amphibians; biogeography; diversification rate; Holarctic; transcontinental dispersal.


Assuntos
Filogenia , Ranidae/classificação , América , Animais , Ásia , Teorema de Bayes , Ásia Oriental , Ranidae/genética , Análise de Sequência de DNA
6.
Zootaxa ; (3796): 401-34, 2014 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-24870685

RESUMO

We describe two new mountain-dwelling microhylid species of the genus Kalophrynus from the southern part of the Annamite Mountains in Vietnam. The two new species differ from all known congeners in morphological characters and mtDNA; phylogenetically, they form a sister clade to the large-bodied K. interlineatus (1009 bp, 16S rRNA gene, mtDNA). Both species share the following characteristics: snout pointed in dorsal and lateral views, slightly sloping in profile; tympanum distinct, smaller than eye in diameter; toe webbing moderate; outer metatarsal tubercle present; light dorsolateral line absent. Kalophrynus cryptophonus sp. nov. from Loc Bao, Lam Dong Province is a small-sized species distinguishing from its congeners by a combination of: SVL 27.9-30.4 mm in males, 23.4 mm in female; canthus rostralis indistinct; males with large sharp conical spines on the skin covering mandible margins and finely asperous nuptial pads on the dorsal surface of fingers I-III; dark ocelli in the inguinal region usually present, small, without a light border; anterior palatal dermal ridge short, restricted to medial part of palate. Kalophrynus honbaensis sp. nov. from Hon Ba, Khanh Hoa Province is a medium-sized Kalophrynus, distinguishing from its congeners by a combination of: SVL 26.7-36.8 mm in males; canthus rostralis distinct; males without distinguishable spines on the mandible margins nor the nuptial pads; dark ocelli in the inguinal region present, large, without a distinct light border, anterior palatal dermal ridge developed, parallel to posterior one. Kalophrynus cryptophonus sp. nov. reproduces in hollow bamboo stems; we describe larval morphology and bioacoustics of this species in relation to phytotelm breeding. A review of the distribution of the genus Kalophrynus in Indochina is provided.


Assuntos
Anuros/classificação , Filogenia , RNA Ribossômico 16S/genética , Comunicação Animal , Animais , Anuros/anatomia & histologia , Anuros/genética , Ecossistema , Feminino , Larva/anatomia & histologia , Masculino , Especificidade da Espécie , Vietnã
7.
Zootaxa ; 5406(1): 87-104, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38480163

RESUMO

A new species of dibamid lizard, Dibamus deimontis sp. nov., is described based on eight specimens collected from the highlands of Nui Chua Mountain within Nui Chua National Park, Ninh Thuan Province, southern Vietnam. Dibamus deimontis sp. nov. co-occurs with the recently described Dibamus tropcentr, but is recorded at higher elevations (670700 m a.s.l. vs. 200280 m a.s.l.), and in a different habitat and microhabitats than the previous species. Our study represents the first report on the near sympatric occurrence of two Dibamus species. The new species can be distinguished from other congeners by the following combination of characters: rostral, labial and nasal sutures incomplete; two to three postoculars; three to five scales on the posterior edge of infralabial; 2225 midbody scale rows; 193225 ventral scales; 4755 subcaudal scales; 115 presacral and 27 tail vertebrae (in a single male specimen examined); and maximum snout-vent length 136.2 mm. We suggest this species should be considered as Vulnerable (VU) following the IUCNs Red List categories. Our study brings the number of species in the genus Dibamus to 26; Dibamus deimontis sp. nov. is the eighth species of Dibamus recorded in Vietnam, and underlines the importance of the country as a local center of reptilian diversity in Southeast Asia.


Assuntos
Lagartos , Parques Recreativos , Masculino , Animais , Vietnã , Estruturas Animais , Serpentes , Filogenia , Distribuição Animal
8.
Zootaxa ; 3599: 246-60, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24613873

RESUMO

We describe a new species of the agamid genus Calotes Cuvier, 1817 from southern Vietnam, which is most similar to Calotes mystaceus Duméril & Bibron, 1837, but can be distinguished from the latter and its other congeners by genetic and morphological differences. We discuss the current distribution of the new species and its sister species C. mystaceus in Mainland Southeast Asia.


Assuntos
Lagartos/classificação , Lagartos/genética , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Lagartos/anatomia & histologia , Masculino , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Vietnã
9.
Zootaxa ; 3702: 233-46, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26146721

RESUMO

We describe a new species of the genus Oligodon from the lowland forests of Cat Tien National Park, Dong Nai Province, in southern Vietnam. Oligodon cattienensis sp. nov. is distinguished from the remaining Southeast Asian kukri snakes by the combination of the following characters: medium-sized, deeply forked hemipenes without spines, 17-17-15 dorsal scale rows, nasal entire, 2 small postoculars, almost equal in size, 167-178 ventrals, 31-35 subcaudals, 24-35 + 5 large dark-edged vertebral blotches in combination with a yellow-orange or red vertebral stripe between blotches, head pattern including ocular band, temporal bands and elongated chevron, ventrals pink or whitish (reddish in juveniles) in life, some bearing a quadrangular dark blotch on each lateral side, or ventrals being entirely dark. Based on the hemipenial morphology the new species is assigned to the Oligodon cyclurus species group. A comparison table for all Indochinese Oligodon is provided.


Assuntos
Colubridae/anatomia & histologia , Colubridae/classificação , Animais , Feminino , Masculino , Vietnã
10.
Zootaxa ; 5306(5): 537-550, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37518669

RESUMO

An integrative taxonomic analysis delimits and diagnoses the new species Hemiphyllodactylus cattien sp. nov. from Cat Tien National Park, Dong Nai Province, southern Vietnam-the eighth species of Hemiphyllodactylus to be described from Vietnam. The new species is recovered as the sister species to a clade comprised of H. indosobrinus from Laos and H. flaviventris from Thailand based on phylogenetic analyses using ND2 mtDNA gene sequences. Unlike the vast majority of Hemiphyllodactylus which are site-restricted upland endemics, Hemiphyllodactylus cattien sp. nov. is a lowland species collected from one of the most well-surveyed regions in Vietnam. Its discovery further emphasizes the need for continued re-sampling of survey sites already considered to be well-explored.


Assuntos
Florestas , Lagartos , Animais , Filogenia , Vietnã
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