Tuesday, February 28, 2023

[Herpetology • 2023] Leptobrachella dong • A New Asian Leaf Litter Toad of the Genus Leptobrachella (Anura: Megophryidae) from central south China


Leptobrachella dong
 Liu, Shi, Li, Zhang, Xiang, Wei & Wang, 2023

Dong Leaf Litter Toad | 侗掌突蟾  ||  DOI: 10.3897/zookeys.1149.85895

Abstract
A new species of the Asian leaf litter toad genus Leptobrachella from central south China is described. Molecular phylogenetic analyses, based on mitochondrial 16S rRNA and nuclear RAG1 gene sequences indicated the new species as an independent clade in the genus. The new species could be distinguished from its congeners by a combination of the following characters: body of medium size (SVL 29.2–34.2 mm in 15 adult males and 34.4–43.1 mm in seven adult females); distinct black spots present on flanks; toes rudimentary webbed, with wide lateral fringes; ventral belly white with distinct nebulous brown speckling on ventrolateral flanks; skin on dorsum shagreened with fine tiny granules or short ridges; iris copper above, silver below; heels overlapped when thighs are positioned at right angles to the body; tibia-tarsal articulation reaches the middle eye; dorsal surface of tadpole semi-transparent light brown, spots on tail absent, keratodont row formula I: 3+3/2+2: I; call series basically consist of repeated long calls, at dominant frequency (5093 ± 412 Hz).

Keywords: China, molecular phylogenetic analyses, morphology, new species, taxonomy

Photos of the holotype CIB SSC1757 of Leptobrachella dong sp. nov. in life
A dorsal view B ventral view C dorsolateral view D ventral view of hand E ventral view of foot.

 Leptobrachella dong sp. nov.
Diagnosis: 
Leptobrachella dong sp. nov. is assigned to the genus Leptobrachella, based on molecular data and the following morphological characters: medium size, rounded finger tips, the presence of an elevated inner palmar tubercle not continuous to the thumb, presence of macroglands on body (including supra-axillary, pectoral and femoral glands), vomerine teeth absent, tubercles on eyelids and anterior tip of snout with vertical white bar (Dubois 1983; Fei et al. 2009).

Leptobrachella dong sp. nov. could be distinguished from its congeners by a combination of the following characters: (1) body of medium size (SVL 29.2–32.0 mm in 15 adult males and 37.4–43.1 mm in seven adult females); (2) distinct black spots present on flanks; toes rudimentary webbed, with wide lateral fringes; (3) ventral belly white with distinct nebulous brown speckling on ventrolateral flanks; (4) skin on dorsum shagreened with fine tiny granules or short ridges; (5) heels overlapped when thighs are positioned at right angles to the body; (6) tibia-tarsal articulation reaches the middle eye; (7) dorsal surface of tadpole semi-transparent light brown, spots on tail absent, keratodont row formula I: 3+3/2+2: I; (8) calls with two types, at dominant frequency (5.1 ± 0.4 kHz).

Colour variation in Leptobrachella dong sp. nov.
A dorsolateral view of the male specimen CIB LB20220311002 B dorsal view of the male specimen CIB SCC1754
C dorsal view of the female specimen CIB LB20220305005 D dorsal view of the female specimen CIB LB20220306008.

Habitats of Leptobrachella dong sp. nov. 
A landscape of the type locality Tongdao County, Hunan Province, China B a torrent mountain stream in the type locality (insert holotype CIB SSC1757 in life in the field) 
C habitat at the Congjiang County, Guizhou Province, China D habitat at the Suining County, Hunan Province, China.

Ecology notes: Leptobrachella dong sp. nov. has been found in three localities: Tongdao County and Suining County, Hunan Province and Congjiang County, Guizhou Province, China. Elevations recorded range from 620 m to 1200 m. Population from the Tongdao County inhabited a torrent stream covered by evergreen shrubs and the new species always found on the stones (Fig. 8A, B). Population from Congjiang County inhabited slow-flowing streams surrounded by evergreen broadleaf forest (Fig. 8C). Populations from Suining County, Hunan Province inhabited broad mountain stream surrounded by evergreen broadleaf forest (Fig. 8D). Tadpoles could be found at daytime and night. Gravid females were found by the streams in the type locality (2 April 2017) and Suining County (15 March 2022).

Etymology: This specific name “dong” refers to the Dong people, as the new species distributed in the concentrated area of Dong people. 
We suggest its English common name “Dong leaf litter toads” 
and Chinese name “Dong Zhang Tu Chan (侗掌突蟾)”.


Jing Liu, Shengchao Shi, Shize Li, Mengfei Zhang, Sunjun Xiang, Gang Wei and Bin Wang. 2023. A New Asian Leaf Litter Toad of the Genus Leptobrachella (Amphibia, Anura, Megophryidae) from central south China. ZooKeys. 1149: 103-134. DOI: 10.3897/zookeys.1149.85895