Sunday, July 3, 2011

[Herpetology • 2007] ปาดแคระนิลเนตร | Philautus neelanethrus • ‘blue eye’ Shrub Frog from the Central Western Ghats of India

Philautus neelanethrus sp.nov. amplected pair

Philautus neelanethrus
Gururaja, Aravind, Ali, Ramachandra, Velavan, Krishnakumar & Aggarwal, 2007

Tropical evergreen forests of Indian subcontinent, especially of the Western Ghats, are known hot spots of amphibian diversity, where many new anuran species await to be identified. Here we describe from the Sharavathi River basin of central Western Ghats a new shrub-frog taxon related to the anuran family Rhacophoridae. The new frog possesses the characteristic features of rhacophorids (dilated digit tips with differentiated pads circumscribed by a complete groove, intercalary cartilages on digits, T-shaped terminal phalanges and granular belly, the adaptive characters for arboreal life forms), but also a suite of unique features that distinguish it from all known congeners in the region. Morphogenetic analysis based on morphological characteristics and diversity in the mitochondrial 12S and 16S rRNA genes revealed it to be a new Philautus species that we named Philautus neelanethrus sp. nov. The phylogenetic analysis suggests the new frog to represent a relatively early Philautus species lineage recorded from the region. The distribution pattern of the species suggests its importance as a bioindicator of habitat health. In general, this relatively widespread species was found distributed only in non-overlapping small stretches, which indirectly indicates the fragmentation of the evergreen to moist deciduous forests that characterize the Western Ghats. Thus the discovery of the new rhacophorid species described here not only further reinforces the significance of the Western Ghats as a major hotspot of amphibian biodiversity, but also brings into focus the deterioration of forest habitats in the region and the need for prioritization of their conservation.

Key words: amphibian biodiversity, conservation, shrub frog, Western Ghats, habitat, rDNA diversity

Philautus neelanethrus sp.nov. Male while calling

Etymology: The species name neelanethrus is derivedfrom Sanskrit meaning ‘blue eye’, and is a nominative singular noun standing in apposition to the generic name

Type locality: "Arodi, Sagar Taluk, Shimoga District, Karnataka state (14° 08´ 25 N, 74° 47´ 44E), 534 m asl (meters above sea level), a moist deciduous forest patch", India.
Holotype: BNHS 4510.

Fig. 1. Sharavathi River basin and the type localities of the new Philautus species.

Fig. 2. Characteristic features of P. neelanethrus sp.nov. (a) Male while calling (SVL 29.8 mm, collected from the Nandiholé locality); (b) amplected pair (specimens not collected); (c) ventral view of forelimb; (d) ventral view of hindlimb; (e) dorsolateral view of an adult male.

Gururaja, Aravind, Ali, Ramachandra, Velavan, Krishnakumar, and Aggarwal, 2007. A New Frog Species from the Central Western Ghats of India, and Its Phylogenetic Position. Zoological Science (Zool. Sci.), 24: 525- 534. DOI: 10.2108/zsj.24.52