Wednesday, January 6, 2021

[Herpetology • 2020] Leptobrachella bashaensis • A New Species of the Genus Leptobrachella Smith, 1925 (Anura, Megophryidae) from Guizhou, China


 Leptobrachella bashaensis 
Lyu, Dai, Wei, He, Yuan, Shi, Zhou, Ran, Kuang, Guo, Wei & Yuan, 2020
 
岜沙掌突蟾  ||  DOI: 10.3897/zookeys.1008.56412

Abstract
Asian leaf-litter toads of the genus Leptobrachella represent charismatic anuran diversification with 80 species, of which 25 are from China. Recent new discoveries suggest that the diversity of this genus is underestimated. Here, we describe a new species of LeptobrachellaLeptobrachella bashaensis sp. nov. from the Basha Nature Reserve, Congjiang County, Guizhou Province, China. The new species is distinguished from its congeners by the following suite of morphological traits: small body size (SVL 22.9–25.6 mm in six adult males and 27.1 mm in one adult female); head longer than wide; dorsal skin slightly shagreened with small tubercles; creamy-white chest and belly with irregular black spots; distinct ventrolateral glands forming a white line; finger webbing and fringes absent; toe webbing rudimentary and lateral fringes narrow; iris bicolored with bright orange in upper half and silver in lower half; dorsal surface of tadpole head dark brown with small, brown, irregular spot, air sac-shaped bulges on both sides of body. The new species differs from all known congeners by an uncorrected p-distance of >5.3% of the 16S rRNA gene fragment examined, and the phylogenetic analysis clusters the new species with L. maoershanensis and L. laui. At present, the new species is only known from a small range of montane evergreen secondary forests in Basha Nature Reserve approximately 900 m elevation. Its natural history and conservation status are discussed.

Keywords: Integrated taxonomy, morphology, tadpole, vocalization


Figure 3. Holotype of  Leptobrachella bashaensis sp. nov. (GIB196403) in life 
A frontolateral view B lateral view C iris coloration D W-shaped marking 
E dorsal view of thighs F posterioventral view of thighs G ventral view H throat view.


Leptobrachella bashaensis sp. nov.
 
Diagnosis: The new species is assigned to the genus Leptobrachella on the basis of the following characters: small size, rounded fingertips, presence of an elevated inner palmar tubercle not continuous to the thumb, presence of supra-axillary, femoral and ventrolateral glands, vomerine teeth absent, tubercles on eyelids, and pale vertical bar present on anterior tip of snout (Dubois 1980, 1983; Ohler et al. 2011; Rowley and Cao 2009; Rowley et al. 2013). Leptobrachella bashaensis sp. nov. is distinguished from its congeners by a combination of the following morphological characters: (1) small size (SVL 22.9–25.6 mm in six adult males and 27.1 mm in one adult female), (2) head longer than wide, (3) externally distinct tympanum, (4) dorsal skin slightly shagreened with small tubercles and irregular brown stripes, (5) distinct dark spots on the flank, (6) creamy-white chest and off-white belly with irregular black spots, (7) grey-pinkish to dark brownish-violet ventral skin of limbs with numerous whitish speckles, (8) distinct ventrolateral glands, forming a distinct white line, (9) finger webbing and fringes absent, (10) toe webbing rudimentary and lateral fringes narrow, (11) longitudinal ridges under toes and not interrupted at the articulations, (12) a distinctly bicolored iris, typically bright orange in upper half, fading to silver in lower half.

Etymology: The specific epithet, “bashaensis”/Basha Zhang Tu Chan (岜沙掌突蟾 in Chinese), refers to the location where the specimens were collected, Basha Nature Reserve of Guizhou Province, China.


Figure 7. Paratypes of  Leptobrachella bashaensis sp. nov. in life (GIB196404).

Figure 8. Habitat at the type locality of  Leptobrachella bashaensis sp. nov., Basha Nature Reserve, Congjiang, Guizhou province, China.

Natural history: All specimens were collected at night in small streams in Basha Nature Reserve approximately 900 m elevation (Fig. 8). Calling males were found along the streams, perching on large rocks, in rocky crevices, or under dead wood. Insect-like calls could be heard in June. The breeding season of this species is likely to occur from June to July, as females collected during these months were gravid, and males were heard calling only from June to the beginning of July. During both surveys, the number of males observed was much greater than females (males:females = 12:1).


Jing-Cai Lyu, Liang-Liang Dai, Ping-Fan Wei, Yan-Hong He, Zhi-Yong Yuan, Wen-Li Shi, Sheng-lun Zhou, Si-yu Ran, Zhong-Fan Kuang, Xuan Guo, Gang Wei and Guo Yuan. 2021. A New Species of the Genus Leptobrachella Smith, 1925 (Anura, Megophryidae) from Guizhou, China. ZooKeys. 1008: 139-157. DOI: 10.3897/zookeys.1008.56412