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1.
Zootaxa ; 4661(1): zootaxa.4661.1.2, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31716716

RESUMO

We report the first occurrence of the Asian Rock Gecko genus Cnemaspis Strauch, 1887 from mainland Myanmar based on a series of specimens recently collected from the Tanintharyi Region. These records come from several localities in the Tanintharyi Region and fill a significant sampling gap for the genus. Molecular phylogenetic analyses using the mitochondrial gene ND2 identify two distinct clades, the first includes Cnemaspis siamensis of the Southeast Asian Cnemaspis group and the second includes two new species belonging to the South Asian Cnemaspis kandiana group. These two species are morphologically distinct and are distinguished from all other members in the C. kandiana group by a combination of character states. The first species, Cnemaspis tanintharyi sp. nov. occurs on the mainland in southern Tanintharyi and is distinguished from all congeners by the possession of keeled pectoral scales; smooth ventral scales and abdominal scales; 2-4 precloacal pores; 4-5 femoral pores on each leg; smooth subcaudal scales with the median row enlarged; coloration of the gular region beige, dark gray-brown with dark blue hueing towards throat; 15-18 subdigital lamellae on the 4th toe; and 21-23 ventral scales at midbody. The other, Cnemaspis thayawthadangyi sp. nov. is known only from the island group of Thayawthadangyi, in the Myeik Archipelago and is distinguished from all congeners by the possession of keeled pectoral scales; keeled ventral scales and abdominal scales; three precloacal pores; four femoral pores on each leg; smooth subcaudal scales, scales on median row enlarged; coloration of the gular region silver with dark-gray irregularly shaped streaks; 16-18 subdigital lamellae on the 4th toe; and 18-20 ventral scales at midbody. In addition, we address the taxonomic status of populations referred to as C. kandiana (a species now restricted to Sri Lanka) found in peninsular Thailand and provisionally assign them as C. cf. tanintharyi sp. nov. until further analysis can be conducted. Finally, we briefly discuss the biogeography of the South Asian clade of Cnemaspis.


Assuntos
Lagartos , Distribuição Animal , Estruturas Animais , Animais , Ecossistema , Ilhas , Mianmar , Filogenia , Sri Lanka , Tailândia
2.
Zootaxa ; 4483(2): 295-316, 2018 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-30313789

RESUMO

An integrative phylogenetic analysis recovers two new species of the gekkonid genus Hemiphyllodactylus (Bleeker) from the Shan Hills of eastern Myanmar. Hemiphyllodactylus ywanganensis sp. nov. and H. uga sp. nov. are nested within the eastern Myanmar clade of a previous genus-wide phylogenetic analysis and form a more exclusive monophyletic group with H. linnwayensis. These species differ from each other and all other Hemiphyllodactylus in having unique combinations of character states involving postmental and subcaudal scale morphology; maximum SVL; digital formulae; numbers of chin scales, circumnasals, intersupranasals (=postrostrals), labials, longitudinally arranged dorsal and ventral scales, and pore-bearing femoroprecloacal scales; as well as subtle differences in coloration and pattern. The phylogenetic affinities of the eastern Myanmar clade are similar to those of an endemic clade of Cyrtodactylus from the Shan Hills in that both are more closely related to Indochinese taxa east of Myanmar as opposed to other Indo-Burmese species. The discovery of these new species underscores the underappreciated herpetological diversity of limestone ecosystems as well as the remote nature of the rugged uplands of the Shan Hills and emphasizes the need for continued field work in this region.


Assuntos
Lagartos , Filogenia , Animais , Ecossistema , Mianmar
3.
Zookeys ; (757): 85-152, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29780268

RESUMO

Despite threats of species extinctions, taxonomic crises, and technological advances in genomics and natural history database informatics, we are still distant from cataloguing all of the species of life on earth. Amphibians and reptiles are no exceptions; in fact new species are described nearly every day and many species face possible extinction. The number of described species continues to climb as new areas of the world are explored and as species complexes are examined more thoroughly. The use of DNA barcoding provides a mechanism for rapidly estimating the number of species at a given site and has the potential to record all of the species of life on Earth. Though DNA barcoding has its caveats, it can be useful to estimate the number of species in a more systematic and efficient manner, to be followed in combination with more traditional, morphology-based identifications and species descriptions. Herein, we report the results of a voucher-based herpetological expedition to the Tanintharyi (Tenasserim) Region of Myanmar, enhanced with DNA barcode data. Our main surveys took place in the currently proposed Tanintharyi National Park. We combine our results with photographs and observational data from the Chaung-nauk-pyan forest reserve. Additionally, we provide the first checklist of amphibians and reptiles of the region, with species based on the literature and museum. Amphibians, anurans in particular, are one of the most poorly known groups of vertebrates in terms of taxonomy and the number of known species, particularly in Southeast Asia. Our rapid-assessment program combined with DNA barcoding and use of Barcode Index Numbers (BINs) of voucher specimens reveals the depth of taxonomic diversity in the southern Tanintharyi herpetofauna even though only a third of the potential amphibians and reptiles were seen. A total of 51 putative species (one caecilian, 25 frogs, 13 lizards, 10 snakes, and two turtles) were detected, several of which represent potentially undescribed species. Several of these species were detected by DNA barcode data alone. Furthermore, five species were recorded for the first time in Myanmar, two amphibians (Ichthyophis cf. kohtaoensis and Chalcorana eschatia) and three snakes (Ahaetulla mycterizans, Boiga dendrophila, and Boiga drapiezii).

4.
Zootaxa ; 4347(2): 301-315, 2017 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-29245596

RESUMO

The taxonomic identity of the Trimeresurus (Popeia) popeiorum complex from the Isthmus of Kra and to the north was investigated. Several studies over the last decade have produced several specimens and associated mtDNA sequence data for a variety of individuals of the T. popeiorum and "T. sabahi" complexes. Here, we combine four mitochondrial genes (12S, 16S, ND4, and CytB) from all available specimens in GenBank with the addition of five new specimens collected from the mainland, Tanintharyi Region of Myanmar. Maximum Likelihood and Bayesian analyses identified that T. popeiorum sensu lato is paraphyletic with two geographically distinct clades: a northern clade representing populations from northern Myanmar, Laos and northern Thailand and a southern clade representing samples from the Tanintharyi Region and adjacent west Thailand. While the two clades have considerable genetic distance, they appear to be morphologically identical, leading to the hypothesis that the southern clade represents a cryptic, undescribed species. Because they appear to be cryptic species and the limitation of only five specimens from the southern lineage, this does not permit us to formally describe the new species. In accordance to past molecular studies, we uncovered paraphyly and lack of genetic support for the validity of taxa within the T. sabahi complex. However, we suggest recognizing these populations as subspecies within T. sabahi.


Assuntos
Trimeresurus , Animais , Teorema de Bayes , DNA Mitocondrial , Laos , Mianmar , Filogenia , Análise de Sequência de DNA , Tailândia
5.
PLoS One ; 12(4): e0174432, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28403189

RESUMO

Myanmar's recent transition from military rule towards a more democratic government has largely ended decades of political and economic isolation. Although Myanmar remains heavily forested, increased development in recent years has been accompanied by exceptionally high rates of forest loss. In this study, we document the rapid progression of deforestation in and around the proposed Lenya National Park, which includes some of the largest remaining areas of lowland evergreen rainforest in mainland Southeast Asia. The globally unique forests in this area are rich in biodiversity and remain a critical stronghold for many threatened and endangered species, including large charismatic fauna such as tiger and Asian elephant. We also conducted a rapid assessment survey of the herpetofauna of the proposed national park, which resulted in the discovery of two new species of bent-toed geckos, genus Cyrtodactylus. We describe these new species, C. lenya sp. nov. and C. payarhtanensis sp. nov., which were found in association with karst (i.e., limestone) rock formations within mature lowland wet evergreen forest. The two species were discovered less than 35 km apart and are each known from only a single locality. Because of the isolated nature of the karst formations in the proposed Lenya National Park, these geckos likely have geographical ranges restricted to the proposed protected area and are threatened by approaching deforestation. Although lowland evergreen rainforest has vanished from most of continental Southeast Asia, Myanmar can still take decisive action to preserve one of the most biodiverse places on Earth.


Assuntos
Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Lagartos/genética , Distribuição Animal , Animais , Feminino , Florestas , Variação Genética , Lagartos/anatomia & histologia , Masculino , Mianmar , Parques Recreativos , Filogenia , Análise de Sequência de DNA
6.
Zookeys ; (657): 141-156, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28331413

RESUMO

Recent fieldwork in southern Tanintharyi revealed the presence of a small Green Crested Lizard in the wet evergreen forest. We generated mtDNA sequence data (ND2) that demonstrates that this population's nearest relative is Bronchocela rayaensis Grismer et al., 2015 of Pulau Langkawi, northwestern Peninsular Malaysia and Phuket Island. Morphologically the Burmese Bronchocela shares many features with Bronchocela rayaensis, which potentially would make this recently described Thai-Malay species a synonym of Bronchocela burmana Blanford, 1878; however, we interpret the genetic and morphological differences to reflect evolutionary divergence and recommend the recognition of both species.

7.
PLoS One ; 9(5): e97682, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24837300

RESUMO

Vertebrates are currently going extinct at an alarming rate, largely because of habitat loss, global warming, infectious diseases, and human introductions. Island ecosystems are particularly vulnerable to invasive species and other ecological disturbances. Properly documenting historic and current species distributions is critical for quantifying extinction events. Museum specimens, field notes, and other archived materials from historical expeditions are essential for documenting recent changes in biodiversity. The Islas Revillagigedo are a remote group of four islands, 700-1100 km off the western coast of mainland México. The islands are home to many endemic plants and animals recognized at the specific- and subspecific-levels, several of which are currently threatened or have already gone extinct. Here, we recount the initial discovery of an endemic snake Hypsiglena ochrorhyncha unaocularus Tanner on Isla Clarión, the later dismissal of its existence, its absence from decades of field surveys, our recent rediscovery, and recognition of it as a distinct species. We collected two novel complete mitochondrial (mt) DNA genomes and up to 2800 base-pairs of mtDNA from several other individuals, aligned these with previously published mt-genome data from samples throughout the range of Hypsiglena, and conducted phylogenetic analyses to infer the biogeographic origin and taxonomic status of this population. We found the Isla Clarión population to be most closely related to populations in the Sonora-Sinaloa state border area of mainland México and Isla Santa Catalina, in the Gulf of California. Based on genetics, morphology, and geographic distributions, we also recognize these two other lineages as distinct species. Our study shows the importance of museum specimens, field notes, and careful surveys to accurately document biodiversity and brings these island endemics (Clarión and Santa Catalina nightsnakes) and mainland population near the Sonora-Sinaloa state border to the attention of conservation biologists currently monitoring biodiversity in these fragile subtropical ecosystems.


Assuntos
Serpentes/classificação , Serpentes/genética , Animais , Biodiversidade , California , DNA Mitocondrial , Genoma Mitocondrial , Ilhas , México , Oceano Pacífico , Filogenia
8.
J Hered ; 102(1): 29-37, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20805288

RESUMO

Evolution of population structure on islands is the result of physical processes linked to volcanism, orogenic events, changes in sea level, as well as habitat variation. We assessed patterns of genetic structure in the giant tortoise of the Aldabra atoll, where previous ecological studies suggested population subdivisions as a result of landscape discontinuity due to unsuitable habitat and island separation. Analysis of mitochondrial DNA (mtDNA) control region sequences and allelic variation at 8 microsatellite loci were conducted on tortoises sampled in 3 locations on the 2 major islands of Aldabra. We found no variation in mtDNA sequences. This pattern corroborated earlier work supporting the occurrence of a founding event during the last interglacial period and a further reduction in genetic variability during historical time. On the other hand, significant population structure recorded at nuclear loci suggested allopatric divergence possibly due to geographical barriers among islands and ecological partitions hindering tortoise movements within islands. This is the first attempt to study the population genetics of Aldabra tortoises, which are now at carrying capacity in an isolated terrestrial ecosystem where ecological factors appear to have a strong influence on population dynamics.


Assuntos
Evolução Molecular , Loci Gênicos , Variação Genética , Genética Populacional , Tartarugas/genética , Alelos , Animais , DNA Mitocondrial/genética , Ecossistema , Fluxo Gênico , Geografia , Ilhas do Oceano Índico , Repetições de Microssatélites , Filogenia , Filogeografia , Dinâmica Populacional
9.
Mol Phylogenet Evol ; 57(1): 227-36, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20541614

RESUMO

Competition heavily influences the structure of island communities, particularly in species-rich areas. If ecologically similar lineages come into contact following dispersal, selection may favor rapid evolutionary change; if constraints prevent such change, lineage extinction may result. One mechanism for relieving competition among newly sympatric species is the evolution of body size differences, such as through character displacement or size assortment. The Crocodile skinks of the genus Tribolonotus exhibit a threefold variation in body size, and several species occur in sympatry. We use 2252 bp of DNA sequence data spanning two mitochondrial (cyt b and ND2) and three nuclear (C-mos, Rhodopsin and Phosducin) gene regions to reconstruct the phylogeny of Tribolonotus, use it to examine the biogeography of the genus, and test for size assortment or character displacement. We find evidence that Tribolonotus originated on either Greater Bougainville or in New Guinea, and subsequently colonized surrounding islands via multiple colonization events. Our ancestral state reconstructions support multiple instances of parallel and independent change in body size within Tribolonotus. Additionally, we find no evidence for size assortment and conflicting evidence for character displacement, which we argue suggests that character displacement, combined with ecological differences between New Guinean species (T. gracilis and T. novaeguineae), best explains the evolution of body size in the genus Tribolonotus.


Assuntos
Tamanho Corporal , Evolução Molecular , Lagartos/genética , Filogenia , Animais , Núcleo Celular/genética , DNA Mitocondrial/genética , Geografia , Lagartos/anatomia & histologia , Lagartos/classificação , Ilhas do Pacífico , Filogeografia , Análise de Sequência de DNA
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