Rohanixalus hansenae ( Cochran, 1927 ) Biju & Garg & Gokulakrishnan & Chandrakasan & Thammachoti & Ren & Gopika & Bisht & Hamidy & Shouche, 2020

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 : 39-40

Rohanixalus hansenae ( Cochran, 1927) comb. nov.

Hansen’s Bubble-nest Frog

( Figs. 1–2 , 4 , 7 , 16 ; Tables 1 , 3 , 4 )

Original name and description. Philautus hansenae Cochran, 1927 . Cochran D.M. 1927. New reptiles and batrachians collected by Dr. Hugh M. Smith in Siam. Proceedings of the Biological Society of Washington, 40: 179–192.

Type. Holotype, USNM 70109 , by original designation. Type locality. “Nong Khor, southeastern Siam”, Thailand. Current status of specific name. Valid name as Rohanixalus hansenae ( Cochran, 1927) comb. nov.

Taxonomic remarks. Based on the morphological and phylogenetic evidence presented in this study, this species is a member of the genus Rohanixalus . The taxon was originally described from southeastern Thailand and subsequently reported to have a wide distribution within Thailand. Stuart and Emmett (2006) doubted the validity of the species, however, R. hansenae was not only shown to be phylogenetically, morphologically, and acoustically distinct from R. vittatus ( Aowphol et al. 2013) , but also suggested to comprise of two distinct lineages likely to be separated geographically (as ‘ Feihyla ’ hansenae Group I from central, eastern, and peninsular Thailand including the type locality; and ‘ Feihyla ’ hansenae Group II largely from montane forests in northwestern and western Thailand) ( Aowphol et al. 2013; Yodthong et al. 2014).We further investigated the levels of genetic divergence among various available populations of Rohanixalus hansenae , including new collections from the type locality. Our phylogenetic results concur with the previous studies and show unidentified lineages among the various R. hansenae populations, indicating that it could indeed represent a species complex, requiring detailed morphological studies.

Diagnosis. Small-sized adults (male SVL 18–21 mm, female SVL 24–25 mm) with slender body; snout nearly pointed in dorsal view; dorsal colouration light to dark brown with a reddish tinge; the entire dorsum, lateral surfaces, and dorsal surface of limbs covered with fine dark brown speckles, some speckles clumping together to form dark irregular blotches on the dorsum; a pair of light coloured and contrasting continuous dorsolateral stripes starting from the snout tip, extending over the eyes, and ending close to the vent; lateral surfaces of the head, including tympanic region, darker than dorsal colouration; foot webbing moderate, just above the second subarticular tubercle on either side of toe IV; eggs light green in colour and laid in bubble nests.

Genetic divergence. For the mitochondrial 16S gene, Rohanixalus hansenae differs from other genetically known congeners ( Fig. 1 ) by: 8.3–11.3% from R. baladika ; 8.6–10.7% from R. senapatiensis ; 8.2–10.2% from R. shyamrupus ; and 9.6–14.0% from R. vittatus . For detailed intra-generic comparison see Table 3 . Further, the sampled populations of Rohanixalus hansenae show high uncorrected intraspecific divergences and the following distances are observed between R. hansenae (typical) and its major sub-lineages: 4.4–8.0% for R. cf. hansenae 1 and 4.1–6.7% for R. cf. hansenae 2 ( Table 3 ).

Distribution. Rohanixalus hansenae is widely distributed across Thailand, with presumed distribution in the adjoining regions of Cambodia and Myanmar ( Yodthong et al. 2014) ( Fig. 4 ).

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 7. Members of the genus Rohanixalus. A. Dorsolateral view of R. hansenae from the type locality, Nong Khor, Thailand; B. dorsolateral view of R. marginis (holotype) from Perlis State Park chalets, Perlis, Peninsular Malaysia; C. dorsal view of R. cf. nauli, from Batang Gadis National Park, North Sumatra, Indonesia with a jelly-nest; D. dorsolateral view of R. cf. nauli, from Batang Gadis National Park, North Sumatra, Indonesia; E. dorsolateral view of R. cf. nauli, from Bukit Barisan Forest Park, North Sumatra, Indonesia; F. dorsolateral view of R. punctatus (Paratype, JBS 9274) from Gwa, Rakhine State, Myanmar (CC Public domain 3.0; AmphibiaWeb); G. dorsolateral view of R. vittatus from Rangat, Middle Andaman Islands, India; H. dorsolateral view of R. senapatiensis from Manipur, India; I. dorsolateral view of R. shyamrupus from Namdapha, Arunachal Pradesh.

FIGURE 16. Rohanixalus hansenae in life, from the type locality Nong Khor, Thailand. A. Dorsolateral view (male); B. dorsolateral view (female); C. dorsal view; D. enlarged view of the tympanic region showing star-shaped speckles; E. ventral view (female); F. ventral view (male); G. ventral view of hand; H. ventral view of foot; I. schematic illustration of webbing on foot.