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| Micryletta immaculata Yang & Poyarkov, 2021 |
We report on a new amphibian species of the genus Micryletta from Hainan Island, China, based on morphological and molecular analyses. The new species, Micryletta immaculata sp. nov., is diagnosed by a combination of the following morphological characters: medium-sized within genus (SVL 23.3–24.8 mm in males, n=3; 27.7–30.1 mm in females, n=2); dorsum bronze brown to reddish brown in life; dark brown spots and stripes on dorsum and flank absent; flanks largely pigmented with silver white; throat in adult males dark brown; undersides without dark patterns; outer metatarsal tubercle absent; supratympanic fold distinct; webbing between toes basal and poorly developed; tibiotarsal articulation adpressed limb reaching level of tympanum. The new species is divergent from all other congeners based on 16S rRNA gene sequences (3.0%–7.7%). Data on the natural history and male advertisement calls of the new species are provided. Following the IUCN Red List Categories and Criteria, we propose the new species to be listed as Vulnerable B1ab (iii).
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| Figure 1 Phylogenetic relationships and distribution of genus Micryletta and holotype of Micryletta immaculata sp. nov. (KFBG 14271) in life A: Distribution of genus Micryletta (gray shading) and location of examined populations. For locality information see Supplementary Table S1. Dot in center of icon denotes type locality of a species; empty circle denotes locality not included in molecular analysis; star denotes type locality of Micryletta immaculata sp. nov. in Exianling Nature Reserve, Hainan, China. B: Majority-rule consensus tree from 1 000 ML bootstrap pseudoreplicates of Micryletta derived from analysis of 1 088 bp 16S rRNA sequences. Values at nodes correspond to ML BS/BPP, respectively; black circles represent nodes with ML BS and BPP support of >90 and 0.90, respectively; white circles represent nodes with ML BS>90 only or BPP>0.90 only; nodes lacking circles are unsupported. Values in brackets after specimen IDs correspond to locality numbers. C: Holotype of Micryletta immaculata sp. nov. (KFBG 14271), adult male, in life in dorsolateral view. D: Same specimen in ventral view. Photos by J.H. Yang, N.A. Poyarkov, P. Pawangkhanant, Chung-Wei You, and Eki Aprilia Resdiyanti Devung. |
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| Holotype of Micryletta immaculata sp. nov. (KFBG 14271), adult male, in life Photo by J.H. Yang. |
Micryletta immaculata sp. nov.
Chresonymy: Micryletta inornata — Lau & Chan, 2012: 54; Plate 1 (Yinggeling National Nature Reserve, Hainan, China).
Etymology: The specific epithet immaculata (meaning “spotless”, “immaculate”) is a Latin singular feminine adjective in the nominative case and refers to the absence of distinct dark spots or stripes on the dorsum and lateral sides of the body in the new species. We propose “Hainan Paddy Frog” for the common English name and “海南小姬蛙” (Hainan Xiao Ji Wa) for the common Chinese name of the new species.
Diagnosis: The new species is assigned to the genus Micryletta based on its possession of the following morphological characters, which are considered diagnostic for the genus: body size small; vomerine teeth absent; dorsal skin smooth and scattered with flat and small tubercles; forelimbs thin and slender; tympanum roughly distinct; subarticular tubercles on fingers and toes large and very prominent; supernumerary tubercles on palm present and distinct; three metacarpal tubercles; tips of digits round, not expanded into discs, with no peripheral grooves; distinct dermal ridges present under 3rd to 4th toes (Dubois, 1987; Fei et al., 2009).
Micryletta immaculata sp. nov. can be distinguished from its congeners by a combination of the following characters: medium-sized within genus (SVL 23.3–24.8 mm in males, n=3; 27.7–30.1 mm in females, n=2); dorsum bronze brown to reddish brown in life; dark brown spots and stripes on dorsum and flank absent; flanks largely pigmented with silver white; throat in adult males dark brown; undersides without dark patterns; outer metatarsal tubercle absent; supratympanic fold distinct; webbing between toes basal and poorly developed; tibiotarsal articulation adpressed limb reaching level of tympanum.
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| Micryletta immaculata in the natural habitat in Hainan. Note one specimen has no eye (C). Photos by Jianhuan Yang |
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| Breeding microhabitats of Micryletta immaculata in Hainan. A: a breeding water puddle on the surface of a limestone rock in Exianling Nature Reserve, green circle noted the calling male holotype KFBG 14271; B: a breeding pond in Zhufeng of Yinggeling National Nature Reserve on 31 May, 2005, inserted small photo noted a pair in amplexus. Photos by Jianhuan Yang (A) and Bosco P.L. Chan (B). |
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| Different species of Micryletta A - M. aishani, B - M. dissimulans, C - M. erythropoda, D - M. inornata, E - M. cf. lineata, F - M. nigromaculata, G, H - M. steinegeri. Photos by Nick Poyarkov, Parinya Herp Pawangkhanant and Chung-Wei Logan You |
Jian-Huan Yang and Nikolay A. Poyarkov. 2021. A New Species of the Genus Micryletta (Anura, Microhylidae) from Hainan Island, China. Zoological Research. DOI: 10.24272/j.issn.2095-8137.2020.333