Feihyla inexpectata ( Matsui, Shimada, and Sudin, 2014 ), 2018

Biju, S. D., Garg, Sonali, Gokulakrishnan, G., Chandrakasan, Sivaperuman, Thammachoti, Panupong, Ren, Jinlong, Gopika, C., Bisht, Karan, Hamidy, Amir & Shouche, Yogesh, 2020, New insights on the systematics and reproductive behaviour in tree frogs of the genus Feihyla, with description of a new related genus from Asia (Anura, Rhacophoridae), Zootaxa 4878 (1), pp. 1-55 : 24-26

Feihyla inexpectata ( Matsui, Shimada, and Sudin, 2014)

Bornean Jelly-nest Frog

( Figs. 1–2 , 4 , 6 ; Tables 1–2 )

Original name and description. Chiromantis inexpectatus Matsui, Shimada, and Sudin, 2014 . Matsui M., Shimada T., and Sudin A. 2014. First record of the tree-frog genus Chiromantis from Borneo with the description of a new species ( Amphibia: Rhacophoridae ). Zoological Science, 31: 45–51. Type. Holotype, BORNEENSIS 22421, by original designation. Type locality. “Camel Trophy field station (4°54’ N, 116°53’ E; ca. 1050 m a.s.l.) of the Maliau Basin Conservation Area, Sandakan Division, Sabah ”, Malaysia. Current status of specific name. Valid name as Feihyla inexpectata ( Matsui, Shimada, and Sudin, 2014) ( Chan et al. 2018) .

Taxonomic remarks. The species was originally described as Chiromantis inexpectatus and compared with all the congeners, except Chiromantis vittiger ( Boulenger, 1897) presumably because of its placement in the genus Philautus at that time. Chan et al. (2018) transferred Chiromantis inexpectatus to Feihyla , phylogenetically based on its sister relationship with Feihyla kajau . We find that F. inexpectata is indeed morphologically as well as biogeo- graphically closer to F. vittiger than any other known member of the genus. The reproductive mode in F. inexpectata is yet unknown, but based on its morphological and phylogenetic relationship, it is most likely a jelly-nest species.

Diagnosis. Small-sized adults (male SVL 22–23 mm), with a slender body; snout nearly truncate in dorsal view, and truncate in lateral view; dorsal skin shagreened to sparsely granular; dorsal colouration light yellow to light or dark brown with a reddish tinge; dorsum with scattered contrasting dark brown spots; upper arm, loreal, canthal and tympanic regions, lateral surfaces of abdomen, and anterior and posterior parts of thigh non-pigmented (flesh coloured); a narrow white streak starting from the snout tip and extending along the lateral surfaces up to the groin, separates the dorsal and lateral body colouration; the first two fingers opposed to the others; foot webbing moderate, up to or slightly beyond the second subarticular tubercle on either side of toe IV.

Genetic divergence. Phylogenetically, F. inexpectata is closely related to members of the Feihyla vittiger group ( Fig. 1 ). For the 16S mitochondrial gene, it differs by average uncorrected genetic distances of: 10.7–11.1% from F. kajau and 9.5–9.9% from F. vittiger . For interspecific genetic distances with other congeners, see Table 2 .

Distribution. Feihyla inexpectata is currently known only from its type locality in Sabah, on the island of Borneo in eastern Malaysia.

Figures

FIGURE 1. Maximum Likelihood tree showing phylogenetic relationships among 124 representative taxa from all recognised genera of the subfamily Rhacophorinae. Relationships are inferred based on 1,937 bp of mitochondrial (12SrRNA, tRNAVAL, 16SrRNA) and nuclear (RHO and RAG1) genes. Numbers above and below the branches indicate Bayesian Posterior Probabilities and RAxML bootstrap support values, respectively.

FIGURE 2. A–B. DNA Barcoding based on mitochondrial 16S rRNA sequences: A. genus Feihyla; B. genus Rohanixalus gen. nov.; C. distribution of the new genus Rohanixalus. Images represent the corresponding species and their broad geographical ranges.

FIGURE 4. Distribution of genetically confirmed records of all known Feihyla and Rohanixalus members (indicated by circles) and their respective type localities (indicated by triangles). Numbers corresponding to each species are indicated alongside the distribution spots.

FIGURE 6. Members of the Feihyla vittiger group and their nest structure. A. F. inexpectata in dorsolateral view; B. F. kajau in dorsolateral view; C. eggs of F. kajau; D. early development in F. kajau at approximately stage 19; E. F. vittiger in dorsolateral view; F. an egg clutch of F. vittiger with developing embryos (approximately stage 21); G–M. Feihyla vittiger in life: G–J. dorsolateral view; K. dorsal view; L. posterior view of thighs; M. lateral view.