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1.
Zootaxa ; 5406(1): 87-104, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38480163

RESUMEN

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.


Asunto(s)
Lagartos , Parques Recreativos , Masculino , Animales , Vietnam , Estructuras Animales , Serpientes , Filogenia , Distribución Animal
2.
Zootaxa ; 5380(4): 301-320, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38221308

RESUMEN

A new species of the genus Dibamus Dumril & Bibron, 1839 is described based on seven specimens collected from Nui Chua National Park, Ninh Thuan Province, southern Vietnam, the hottest and driest place of the country. Dibamus tropcentr sp. nov. is superficially similar to Dibamus smithi Greer, 1985, but can be distinguished from the latter by: the presence of a rudimentary labial suture; by larger number of subcaudal scales; by comparatively longer tail; by generally larger number of midbody scale rows; by having the interparietal scale not enlarged, subequal to the nuchal scale; by having frontal and frontonasal scales subequal in size as compared to almost twice larger frontal scale in D. smithi; by having three scales posterior to interparietal; by having the medial scale posterior to mental not enlarged; by having three to four scales on the posteromedial edge of infralabials; and by having supralabial scale larger than ocular scale. We suggest the new species should be considered as Vulnerable (VU) following the IUCNs Red List categories. The new species occurs in dry maritime mixed low evergreen forests at elevations of 200280 m a.s.l. and was recorded in association with termite species Globitermes sulphureus (Haviland). Our study brings the total number of species of the genus Dibamus to 25; this is the seventh species of the genus recorded from Vietnam.


Asunto(s)
Bosques , Lagartos , Animales , Vietnam , Estructuras Animales , Serpientes , Filogenia , Distribución Animal
3.
Zool Res ; 41(5): 581-588, 2020 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-32786177

RESUMEN

We report on a new species, Micryletta dissimulans sp. nov., from the lowland forests of southern Thailand, which is described based on molecular and morphological evidence. The new species is characterized by a combination of the following characters: small body size (20.3-22.4 mm in males, 24.4-26.7 mm in females); slender body habitus; head longer than wide; snout rounded in dorsal and lateral view; eye length equal to snout length; tibiotarsal articulation reaching to tympanum; dorsal surface slightly granulated to shagreened; supratympanic fold indistinct, ventrally edged in black with large black spot behind eye; outer metatarsal tubercle absent; dorsum reddish-brown with merging irregular-shaped brown blotches edged in beige, no black spots on dorsum; body flanks brown with large black spots edged in whitish mottling, two large black blotches in axillary and inguinal areas on each side; lateral sides of head black, with white patches on lips absent, whitish mottling on tympanum and axillary region; ventral surface pinkish to bluish-gray, translucent, laterally with dark-brown marbled pattern, medially immaculate; throat in males dark-gray with sparse white mottling laterally; iris copper-orange. The new species is divergent from all other congeners in 16S rRNA gene sequences (5.0%-7.4%). To date, Micryletta dissimulans sp. nov. is only known from a single locality in Saba Yoi District, Songkhla Province, Thailand, at an elevation of 120 m a.s.l., but is also expected to occur in neighboring parts of Malaysia. We suggest Micryletta dissimulans sp. nov. be considered as a Data Deficient (DD) species following the IUCN's Red List categories (IUCN Standards and Petitions Committee, 2019).


Asunto(s)
Anuros/anatomía & histología , Anuros/clasificación , Distribución Animal , Animales , Anuros/genética , Anuros/fisiología , Femenino , Bosques , Masculino , Filogenia , Especificidad de la Especie , Tailandia
4.
PeerJ ; 8: e9411, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32685285

RESUMEN

Frogs of the genus Microhyla include some of the world's smallest amphibians and represent the largest radiation of Asian microhylids, currently encompassing 50 species, distributed across the Oriental biogeographic region. The genus Microhyla remains one of the taxonomically most challenging groups of Asian frogs and was found to be paraphyletic with respect to large-sized fossorial Glyphoglossus. In this study we present a time-calibrated phylogeny for frogs in the genus Microhyla, and discuss taxonomy, historical biogeography, and morphological evolution of these frogs. Our updated phylogeny of the genus with nearly complete taxon sampling includes 48 nominal Microhyla species and several undescribed candidate species. Phylogenetic analyses of 3,207 bp of combined mtDNA and nuDNA data recovered three well-supported groups: the Glyphoglossus clade, Southeast Asian Microhyla II clade (includes M. annectens species group), and a diverse Microhyla I clade including all other species. Within the largest major clade of Microhyla are seven well-supported subclades that we identify as the M. achatina, M. fissipes, M. berdmorei, M. superciliaris, M. ornata, M. butleri, and M. palmipes species groups. The phylogenetic position of 12 poorly known Microhyla species is clarified for the first time. These phylogenetic results, along with molecular clock and ancestral area analyses, show the Microhyla-Glyphoglossus assemblage to have originated in Southeast Asia in the middle Eocene just after the first hypothesized land connections between the Indian Plate and the Asian mainland. While Glyphoglossus and Microhyla II remained within their ancestral ranges, Microhyla I expanded its distribution generally east to west, colonizing and diversifying through the Cenozoic. The Indian Subcontinent was colonized by members of five Microhyla species groups independently, starting with the end Oligocene-early Miocene that coincides with an onset of seasonally dry climates in South Asia. Body size evolution modeling suggests that four groups of Microhyla have independently achieved extreme miniaturization with adult body size below 15 mm. Three of the five smallest Microhyla species are obligate phytotelm-breeders and we argue that their peculiar reproductive biology may be a factor involved in miniaturization. Body size increases in Microhyla-Glyphoglossus seem to be associated with a burrowing adaptation to seasonally dry habitats. Species delimitation analyses suggest a vast underestimation of species richness and diversity in Microhyla and reveal 15-33 undescribed species. We revalidate M. nepenthicola, synonymize M. pulverata with M. marmorata, and provide insights on taxonomic statuses of a number of poorly known species. Further integrative studies, combining evidence from phylogeny, morphology, advertisement calls, and behavior will result in a better systematic understanding of this morphologically cryptic radiation of Asian frogs.

5.
Zool Res ; 40(3): 151-174, 2019 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-31011130

RESUMEN

We describe a new species of the genus Tylototriton from Ingyin Taung Mt., Mohnyin Township, Kachin State, Myanmar, based on morphological and molecular evidence. The new species is assigned to the subgenus Tylototriton s. str. and is clearly distinct from all known congeners by the following characters: medium body size; thin, long tail, lacking lateral grooves; rough skin; truncate snout; wide, protruding supratemporal bony ridges on head, beginning at anterior corner of orbit; weak, almost indistinct sagittal ridge; long, thin limbs, broadly overlapping when adpressed along body; distinct, wide, non-segmented vertebral ridge; 13 or 14 rib nodules; brown to dark-brown background coloration with dull orange-brown to yellowish-brown markings on labial regions, parotoids, rib nodules, whole limbs, vent, and ventral tail ridge. We also briefly discuss biogeography and species diversity of the genus Tylototriton in Myanmar.


Asunto(s)
Distribución Animal/fisiología , Salamandridae/anatomía & histología , Salamandridae/clasificación , Animales , Mianmar , Salamandridae/fisiología , Especificidad de la Especie
6.
Zool Res ; 40(4): 244-276, 2019 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-31204803

RESUMEN

We present a morphological and molecular assessment of the Microhyla fauna of Myanmar based on new collections from central (Magway Division) and northern (Kachin State) parts of the country. In total, six species of Microhyla are documented, including M. berdmorei, M. heymonsi, M. butleri, M. mukhlesuri and two new species described from the semi-arid savanna-like plains of the middle part of the Irrawaddy (Ayeyarwady) River Valley. We used a 2 481 bp long 12S rRNA-16S rRNA fragment of mtDNA to hypothesize genealogical relationships within Microhyla. We applied an integrative taxonomic approach combining molecular, morphological, and acoustic lines of evidence to evaluate the taxonomic status of Myanmar Microhyla. We demonstrated that the newly discovered populations of Microhyla sp. from the Magway Division represent two yet undescribed species. These two new sympatric species are assigned to the M. achatina species group, with both adapted to the seasonally dry environments of the Irrawaddy Valley. Microhyla fodiens sp. nov. is a stout-bodied species with a remarkably enlarged shovel-like outer metatarsal tubercle used for burrowing and is highly divergent from other known congeners (P-distance≥8.8%). Microhyla irrawaddy sp. nov. is a small-bodied slender frog reconstructed as a sister species to M. kodial from southern India (P-distance=5.3%); however, it clearly differs from the latter both in external morphology and advertisement call parameters. Microhyla mukhlesuri is reported from Myanmar for the first time. We further discuss the morphological diagnostics and biogeography of Microhyla species recorded in Myanmar.


Asunto(s)
Anuros/anatomía & histología , Anuros/clasificación , Distribución Animal , Animales , Anuros/genética , ADN Mitocondrial/genética , Femenino , Masculino , Mianmar , Filogenia , ARN Ribosómico/genética , Especificidad de la Especie
7.
Zool Res ; 40(5): 358-393, 2019 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-31502426

RESUMEN

We provide an integrative taxonomic analysis of the Lipinia vittigera species complex from mainland Southeast Asia. Based on examination of external morphology, color pattern, and 681 base pairs of the cytochrome oxidase subunit I (COI) mitochondrial gene, we demonstrate the presence of four morphologically distinct lineages of Lipinia in Vietnam, Cambodia, Thailand, and Malaysia, showing a sequence divergence ranging 15.5%-20.4%. All discovered lineages are discretely diagnosable from one another by a combination of scalation traits and color patterns. A review of the published distribution data and a re-examination of available type material revealed the following results:(1) distribution of L. vittigera (Boulenger, 1894) sensu stricto is restricted to Sundaland and the Thai-Malay Peninsula south of the Isthmus of Kra; (2) L. microcercus (Boettger, 1901) stat. nov. is elevated to full species rank; the species has a wide distribution from central and southern Vietnam across Cambodia to eastern Thailand; we regard Lygosoma vittigerum kronfanum Smith, 1922 and Leiolopisma pranensis Cochran, 1930 as its junior synonyms; (3) Lipinia trivittata sp. nov. occurs in hilly areas of southern Vietnam, Cambodia, and eastern Thailand; and (4) Lipinia vassilievi sp. nov. is currently known only from a narrow area along the Vietnamese-Cambodian border in the foothills of the central Annamite Mountain Range. We further provide an identification key for Lipinia occurring in mainland Southeast Asia.


Asunto(s)
Lagartos/genética , Lagartos/fisiología , Pigmentación , Distribución Animal , Animales , Indochina , Especificidad de la Especie
8.
Zootaxa ; 4543(4): 549-580, 2019 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-30647285

RESUMEN

We describe a new species of Microhyla from Tram Lap forest, Gia Lai Province, Central Vietnam based on morphological, molecular, and acoustic data. The new species resembles M. butleri morphologically, but differs from all congeners by a combination of the following morphological attributes: (1) medium-sized adult snout-vent length 25.2-27.0 mm in 15 males and 30.5 mm in a single female; (2) body habitus moderately stocky; (3) head flat, snout rounded, slightly prominent in ventral profile; (4) dorsum and flanks slightly shagreened with evenly scattered tiny tubercles, ventral skin smooth; (5) first finger well developed, more than one-half the length of the second finger; (6) tips of three outer fingers slightly enlarged, forming weak disks and tips of all toes distinctly dilated into wide disks with narrow peripheral grooves; (7) finger and toe disks with dorsal median longitudinal grooves; (8) three palmar tubercles and two metatarsal tubercles; (9) tibiotarsal articulation of adpressed limb reaching slightly beyond the orbit; (10) webbing formula: I 1¾-2 II 1½-2¾ III 2-31/3 IV 3»-1½ V; (11) in life, chin and throat yellowish to bright-orange with tiny dark brown speckling laterally; and (12) a call consisting of 15-26 pulses with a dominant frequency of 1.8-2.2 kHz (recorded at 18.5ºC). We also provide a preliminary genealogy of Microhyla based on analysis of a 2644 bp fragment of 12S-16S rRNA mitochondrial DNA. Based on the examed data, the new species and M. butleri are sister-species (genetic p-distance: 9.0%) and it can be distinguished from M. butleri by its morphology (size, webbing on toes, color) and advertisement call. Interspecific genetic p-distances between the new species and its congeners vary from 9.0% to 14.8%. Microhyla aurantiventris sp. nov. occurs in evergreen montane tropical forests at elevations around 1200 m a.s.l. and is known only from the type locality. The new species appears to be threatened due to intensive logging and agriculture plantation.


Asunto(s)
Anuros , ARN Ribosómico 16S , Animales , Anuros/genética , Femenino , Bosques , Masculino , Filogenia , Vietnam
9.
PeerJ ; 6: e5771, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30310757

RESUMEN

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.

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