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| Micryletta melanops Poyarkov, Nguyen, Yang & Gorin, 2021 |
We report a new species of the genus Micryletta from the montane evergreen forest in the Bidoup-Nui Ba National Park, Lam Dong Province, Langbian Plateau, southern Vietnam, based on molecular and morphological evidence. The new species is diagnosed by a combination of the following morphological characters: body size small (snout-vent length (SVL) 22.4 mm, single female); iris uniform black; snout nearly truncate in dorsal view, slightly rounded in profile; tibiotarsal articulation of adpressed limb reaching level of eye; dorsal surface smooth; supratympanic fold present, prominent; outer metatarsal tubercle absent; tips of toes very weakly dilated into small discs; finger webbing absent, toe webbing rudimentary; dorsal surfaces of head and body orange-red with small irregularly shaped dark-brown patches; dorsal surface of limbs pale dark brown with small reddish speckles; body flanks dark brown anteriorly fading to grayish brown posteriorly with brown spots in groin area; lateral sides of head immaculate blackish brown without white patches; coloration of ventral surfaces immaculate dark gray. The new species is divergent from all other congeners in 16S rRNA gene sequences (2.6%–5.8%). Following the IUCN Red List Categories and Criteria, we propose the new species be listed as Data Deficient (DD).
Micryletta melanops sp. nov.
Chresonymy: Micryletta cf. inornata — Poyarkov [Paiarkov] & Vassilieva (2011):
186–187, 211, Fig. 5.26.
186–187, 211, Fig. 5.26.
Diagnosis: The new species is assigned to the genus Micryletta Dubois, 1987 based on the following morphological attributes: body size small; vomerine teeth absent; tympanum small, rounded, externally visible; subarticular tubercles on fingers and toes very prominent; three well-developed metacarpal tubercles; distinct supernumerary palmar and metatarsal tubercles posterior to base of digits; first finger not reduced; webbing on fingers absent and on toes rudimentary (Alhadi et al., 2019; Das et al., 2019; Dubois, 1987; Munir et al., 2020; Poyarkov et al., 2018; Yang & Poyarkov, 2021).
Micryletta melanops sp. nov. is distinguished from all congeners based on a combination of the following morphological characters: body size small (SVL 22.4 mm, single female); iris uniform black; snout truncate in dorsal view, nearly truncate in profile; tibiotarsal articulation of adpressed limb reaching eye level; dorsal surface smooth; supratympanic fold present, prominent; outer metatarsal tubercle absent; tips of toes weakly dilated into small discs; finger webbing absent, toe webbing rudimentary between toes II–III and III–IV; coloration of dorsal surfaces on head and body orange-red with small irregularly shaped brown patches; dorsal surface of limbs pale dark brown with small reddish speckles; flanks dark brown anteriorly, fading to grayish brown posteriorly with brown spots in groin area; lateral sides of head blackish brown, lacking white patches; coloration of ventral surfaces immaculate dark gray; tadpoles with distinct yellow blotches across tail and fin.
Etymology: Specific epithet “melanops” is an adjective in the nominative case derived from the Ancient Greek “melanos” for “black” and “ops” for “eye” and is given in reference to the characteristic uniform black iris coloration found in the new species.
We recommend “Black-eyed Paddy Frog” for the common English name and “Nhái bầu mắt đen” for the common Vietnamese name of the new species.
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| Iris coloration in eleven species of the genus Micryletta. A – Micryletta aishani (Sagaing, Myanmar); B – M. dissimulans (Songkhla, Thailand); C – M. erythropoda (Dak Lak, Vietnam); D – M. hekouensis (Yunnan, China); E – M. immaculata (Hainan, China); F – M. inornata (North Sumatra, Indonesia); G – M. lineata (Nakhon Si Thammarat, Thailand); H – M. nigromaculata (Hai Phong, Vietnam); I – M. steinegeri (Taiwan, China); J – M. sumatrana (South Sumatra, Indonesia); K – Micryletta melanops sp. nov. (Lam Dong, Vietnam). |
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| A: Distribution of Micryletta genus (gray) and location of examined populations. For locality information, see Supplementary Table S1. Dot in center of an icon denotes type locality of a species; star denotes type locality of Micryletta melanops sp. nov. in Bidoup-Nui Ba NP, Lam Dong Province, southern Vietnam. C: Holotype of Micryletta melanops sp. nov. (ZMMU A7583), adult female, in life in dorsolateral view. D: Tadpole of Micryletta melanops sp. nov. (ZMMU NAP-01381-5) (Gosner stage 37) in lateral view. Photos by N.A. Poyarkov, J.H. Yang, P. Pawangkhanant, Chung-Wei You, and Eki Aprilia Resdiyanti Devung. |
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| Phylogenetic relationships of Micryletta genus B: Consensus BI tree showing genealogical relationships of Micryletta derived from analysis of 1 036 bp of 16S rRNA sequences. Values at nodes correspond to BPP/UFB, respectively; black circles represent nodes with BPP and UFB support >0.95 and 95%, respectively; white circles represent nodes with BPP support >0.90 only or UFB >90% only; nodes lacking circles are not supported. Values in brackets after specimen IDs correspond to locality numbers. Photos by N.A. Poyarkov, J.H. Yang, P. Pawangkhanant, Chung-Wei You, and Eki Aprilia Resdiyanti Devung. |
Nikolay A. Poyarkov, Tan Van Nguyen, Jian-Huan Yang and Vladislav A. Gorin. 2021. A New Species of Micryletta (Amphibia: Anura: Microhylidae) from the Langbian Plateau in southern Vietnam. Zoological Research. 42(6); 726-733. DOI: 10.24272/j.issn.2095-8137.2021.228
