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1.
PeerJ ; 6: e5771, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30310757

RESUMO

We report on a new species of the genus Micryletta from limestone karst areas in northern Vietnam, which is described on the basis of molecular and morphological evidence. Micryletta nigromaculata sp. nov. is restricted to narrow areas of subtropical forests covering karst massifs in Cat Ba National Park (Hai Phong Province) and Cuc Phuong National Park (Ninh Binh Province) at elevations of 90-150 m a.s.l. In the phylogenetic analyses, the new species is unambiguously positioned as a sister lineage to all remaining species of Micryletta. We also discuss genealogical relationships and taxonomic problems within the genus Micryletta, provide molecular evidence for the validity of M. erythropoda and discuss the taxonomic status of M. steinegeri. We suggest the new species should be considered as Endangered (B1ab(iii), EN) following the IUCN's Red List categories. A discussion on herpetofaunal diversity and conservation in threatened limestone karst massifs in Southeast Asia is provided.

2.
PeerJ ; 6: e5584, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30186706

RESUMO

We describe a new species of the genus Leptobrachium from the Khao Laem Mountain, Suan Phung District, Ratchaburi Province, Tenasserim Region, western Thailand, based on molecular and morphological evidences. The new species, Leptobrachium tenasserimense sp. nov., can be distinguished from all other congeners by the following combination of characters: (1) adult SVL of 41.4-58.8 mm in males and 54.7-58.6 mm in females; (2) rounded finger and toe tips; (3) relative finger lengths: II

3.
Zootaxa ; 4388(1): 1-21, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29690461

RESUMO

Morphological, acoustic and molecular analyses result in the description of Leptolalax rowleyae sp. nov., a new species of frog in the Megophryidae, belonging to the L. applebyi Rowley Cao species group from central Vietnam. It differs from its congeners by a combination of the following morphological attributes: (1) adult SVL 23.4-25.4 mm in males and 27-27.8 mm in females; (2) presence of distinct dark/brown dorsolateral markings, including black spots on flanks; (3) pinkish milk-white to light brown chest and belly with numerous white speckles; (4) tympanum distinct; (5) absence of webbing or lateral dermal fringes on fingers and toes; (6) pectoral glands comparatively small (3.3-4.7% of SVL); (7) ventrolateral glands indistinct; and (8) iris bicolored with copper tint in upper half fading to golden in lower third of iris. The male advertisement call of the new species consists of 4-6 notes, lacking a distinct introductory note, with an average dominant frequency of 3.2-3.5 kHz. The description of the tadpole constitutes the first description of larval morphology for a member of the L. appleybi species group. Genetically, an uncorrected sequence divergence of 7.4% for 16S rRNA separates the new species from its two closest relatives, L. ardens and L. melicus in the L. applebyi species group.


Assuntos
Anuros , Animais , Asteraceae , Feminino , Masculino , Núcleo Familiar , Filogenia , RNA Ribossômico 16S , Vietnã
4.
Zool Res ; 39(3): 185-201, 2018 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-29643325

RESUMO

We describe a new species of megophryid frog from Phu Yen Province in southern Vietnam. Leptolalax macrops sp. nov. is distinguished from its congeners by a combination of the following morphological attributes: (1) body size medium (SVL 28.0-29.3 mm in three adult males, 30.3 mm in single adult female); (2) supra-axillary glands present, creamy white; ventrolateral glands indistinct; (3) tympanum externally distinct; (4) dorsal skin roughly granular with larger tubercles, dermal ridges on dorsum absent; (5) rudimentary webbing present between fingers I-II and II-III; rudimentary webbing between all toes; fingers and toes without dermal fringes; (6) in life ventral surface greyish-violet with white speckling; (7) supratympanic fold distinct, dark brown in life; (8) iris bicolored, typically golden in upper half, fading to golden green in lower half; (9) tibia short (TbL/SVL 0.44-0.45 in males); and (10) eyes large and protuberant (ED/SVL 0.15-0.16 in males). From all congeners for which comparable sequences are available, the new species differs markedly in the 16S rRNA mitochondrial gene sequence (P-distance>5.7%). The new species is currently known only from montane evergreen tropical forests of Song Hinh District, Phu Yen Province, and M'Drak District of Dak Lak Province at elevations of 470-630 m a.s.l. We suggest the new species should be considered as Data Deficient following the IUCN's Red List categories. We also report a previously unknown Leptolalax mtDNA lineage from an evergreen tropical forest in the Hoa Thinh District of Phu Yen Province, which may also represent an undescribed species.


Assuntos
Anuros/anatomia & histologia , Animais , Anuros/classificação , Anuros/genética , Feminino , Masculino , RNA Ribossômico 16S/genética , Vietnã
5.
Zool Res ; 39(3): 130-157, 2018 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-29683109

RESUMO

We report on the discovery of a new genus of microhylid subfamily Asterophryinae from northern and eastern Indochina, containing three new species. Vietnamophryne Gen. nov. are secretive miniaturized frogs (SVL<21 mm) with a mostly semi-fossorial lifestyle. To assess phylogenetic relationships, we studied 12S rRNA-16S rRNA mtDNA fragments with a final alignment of 2 591 bp for 53 microhylid species. External morphology characters and osteological characteristics analyzed using micro-CT scanning were used for describing the new genus. Results of phylogenetic analyses assigned the new genus into the mainly Australasian subfamily Asterophryinae as a sister taxon to the genus Siamophryne from southern Indochina. The three specimens collected from Gia Lai Province in central Vietnam, Cao Bang Province in northern Vietnam, and Chiang Rai Province in northern Thailand proved to be separate species, different both in morphology and genetics (genetic divergence 3.1%≤P≤5.1%). Our work provides further evidence for the "out of Indo-Eurasia" scenario for Asterophryinae, indicating that the initial cladogenesis and differentiation of this group of frogs occurred in the Indochina Peninsula. To date, each of the three new species of Vietnamophryne Gen. nov. is known only from a single specimen; thus, their distribution, life history, and conservation status require further study.


Assuntos
Anuros/genética , Animais , Anuros/anatomia & histologia , Anuros/classificação , Indochina , Filogenia , RNA Ribossômico/genética
6.
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
7.
Zookeys ; (672): 49-120, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28769667

RESUMO

Asian Mountain Toads (Ophryophryne) are a poorly known genus of mostly small-sized anurans from southeastern China and Indochina. To shed light on the systematics within this group, the most comprehensive mitochondrial DNA phylogeny for the genus to date is presented, and the taxonomy and biogeography of this group is discussed. Complimented with extensive morphological data (including associated statistical analyses), molecular data indicates that the Langbian Plateau, in the southern Annamite Mountains, Vietnam, is one of the diversity centres of this genus where three often sympatric species of Ophryophryne are found, O. gerti, O. synoria and an undescribed species. To help resolve outstanding taxonomic confusion evident in literature (reviewed herein), an expanded redescription of O. gerti is provided based on the examination of type material, and the distributions of both O. gerti and O. synoria are considerably revised based on new locality records. We provide the first descriptions of male mating calls for all three species, permitting a detailed bioacoustics comparison of the species. We describe the new species from highlands of the northern and eastern Langbian Plateau, and distinguish it from its congeners by a combination of morphological, molecular and acoustic characters. The new species represents one of the smallest known members of the genus Ophryophryne. At present, the new species is known from montane evergreen forest between 700-2200 m a.s.l. We suggest the species should be considered Data Deficient following IUCN's Red List categories.

8.
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
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