Thursday, December 22, 2011

[Herpetology • 2004] Rana iriodes & Rana tabaca • 2 new Cascade Frog from Northeastern Vietnam | Herpetofaunal Diversity of Ha Giang Province

Fig. 6. Frog species from Ha Giang Province, Vietnam:
(A) paratype of Rana iriodes, new species (AMNH 163928), adult male, SVL 42.80 mm; (B) paratype of Rana iriodes, new species; (C) paratype of Rana tabaca, new species (AMNH 163915), adult male, SVL 59.18 mm; (D) paratype of Rana tabaca, new species (AMNH 163920), adult female, SVL 103.40 mm

In April and May of 2000, herpetological surveys of Ha Giang Province, Vietnam, near the Chinese border were undertaken. Surveys concentrated on isolated forests of Mount Tay Con Linh II (contiguous with the highest peak in eastern Vietnam, Mt. Tay Con Linh). The 26-day survey yielded 36 species of amphibians and 16 species of reptiles. The collection contains elements of Himalayan as well as Indo-Malayan assemblages and documents a new country record (Philautus rhododiscus), eight new records east of the Red River (Bombina microdeladigitora, Megophrys parva, Amolops chapaensis, Chaparana delacouri, Chirixalus gracilipes, Philautus odontotarsus, Polypedates dugritei, Rhacophorus hoanglienensis), seven species complexes (Fejervarya limnocharis, Hoplobatrachus rugulosus, Limnonectes kuhlii, Rana chloronota, R. maosonensis, Polypedates dugritei, and P. leucomystax), three unidentified amphibian species, and two previously undescribed species of cascade ranid (Rana iriodes, new species and Rana tabaca, new species).

Rana iriodes differs from R. daorum and Amolops chunganensis in having an iridescent green-gold dorsum, orange-red dorsolateral folds, a goldwhite flank spot, vomerine teeth, and webbing to toe disks. Rana tabaca, new species, can be differentiated from other cascade ranids by a combination of characters: mottled brown upper lip, gold lip line below the eye to the arm insertion, shagreened dorsum, dorsolateral folds, and unpigmented eggs. Species accumulation curves indicate that the diversity of the region is still underestimated, which, along with the relatively extensive remnant forest, underscores the importance for a greater faunal understanding and conservation effort for the montane forests of the region.

— New species —

Rana iriodes

ETYMOLOGY: The specific name is from the Latin iriodes, meaning iridescent. This refers
to the iridescent nature of the skin in life.

DISTRIBUTION: This species is currently known only from Mt. Tay Con Linh II in northeastern Vietnam: Ha Giang Province, Vi Xuyen District, Cao Bo Commune.

REMARKS: Neither tadpoles nor vocal recordings were collected for this species. Male specimens exhibit gular pouches that are either loose and baggy (distended) or tight, appearing as folds of skin at the corner of the jaw.

Rana tabaca

ETYMOLOGY: The specific name is derived from the Latin tabacum, meaning tobacco. The dark brown of R. tabaca is close to the color of thuoc lao, a tobacco common in northern Vietnam.

DISTRIBUTION: This species is currently known only from Ha Giang Province in northern Vietnam: Mt. Tay Con Linh II, Cao Bo Commune, Vi Xuyen District, and Mt. Muong Cha, Du Gia commune, Yen Minh District.

REMARKS: Males were calling a single, loud, high birdlike chirp. They were found on streamside rock ledges and low-lying foliage and on branches 1–3 m over the stream. A female was seen in a small crevice under rocks. Males and females easily scale the rocks among the cascades they inhabit. Tadpoles remain unknown.

Raoul H. Bain and Nguyen Quang Trong. 2004. Herpetofaunal Diversity of Ha Giang Province in Northeastern Vietnam, with Descriptions of Two New Species. American Museum Novitates. 3453