Sunday, July 10, 2011

[Herpetology • 2010] Leptolalax melicus | Musical Asian Leaf Litter Toad • Megophryid frog from northeastern Cambodia

This new species of Asian Leaf Litter Toad, Leptolalax melicus, from Cambodia was described by Dr Jodi Rowley and her colleagues in 2010.:

Leptolalax melicus Rowley, Stuart, Thy & Emmett, 2010

We describe a new species of megophryid frog in the genus Leptolalax from the Kon Tum Plateau in northeastern Cambodia. Leptolalax melicus sp. nov. is distinguished from its congeners by a combination of an off-white to pale pink ventral surface with diffuse dark brown blotches and distinct white speckling, finger I < II, an absence of webbing and dermal fringes on fingers, slight basal webbing and no dermal fringes on toes, body size (19.5–22.7 mm for seven adult males), an absence of ventrolateral glandular lines, dorsum mostly smooth with no skin ridges, and a unique advertisement call consisting of a single long introductory note containing 8–50 pulses, followed by 3–11 predominantly single-pulsed notes, and with an average dominant frequency of 3560–3610 Hz. Leptolalax melicus can be further distinguished from the morphologically similar L. applebyi in having more distinct dorsal patterning, and significantly larger pectoral and femoral glands. Leptolalax melicus and L. applebyi also differ by 6.1% sequence divergence at the 16S mtDNA gene. All specimens of L. melicus were found near rocky streams in evergreen forest between 650–850 m elevation. We suggest the new species should be considered Data Deficient following IUCN’s Red List categories.

Key words: Acoustics, Anura, Leptolalax melicus sp. nov., Ratanakiri, Cambodia, Southeast Asia

Type locality: On 2 cm diameter tree root, 0.5 m from 2 m wide, swift, rocky stream in Virachey National Park, Ratanakiri Province, Cambodia (14.19287° N, 106.99612° E, 650 m, ...).
Holotype: MVZ 258198, by original designation.

Etymology: Specific name from melicus L., meaning musical or lyrical, in reference to the complex call structure of the new species.

FIGURE 1. Collection sites of Leptolalax melicus sp. nov. from Virachey National Park, Cambodia (black circles), Leptolalax applebyi from Song Thanh Proposed Nature Reserve, Vietnam (dark grey square; Rowley & Cao 2009) and Leptolalax sp. from the Cardamom Mountains, Cambodia (dark grey triangle; Ohler et al. 2002). Areas over 600 m elevation are pale grey. Boundaries of Virachey National Park (hatched area) were obtained from the World Database on Protected Areas 2009.

FIGURE 2. Male holotype of Leptolalax melicus sp. nov. (MVZ 258198) in life. (A) Lateral view in the field, in calling posture (nocturnal ventral colouration), (B) dorsal and (C) ventral views (diurnal ventral colouration).

Rowley, J.L., B.L. Stuart, N. Thy & D.A. Emmett. 2010. A new species of Leptolalax (Anura: Megophryidae) from northeastern Cambodia. Zootaxa, 2567: 57–68. Fulltext from