Tonkin Bug-eyed Frog (Theloderma corticale) Familie: Afro-Asian Tree Frogs (Rhacophoridae) Orden: Frogs and Toads (Anura)

Size:  Females 6,9-7,6 cm, males 6,4-7,2 cm. Distribution:  Northern Vietnam (Mao Son og Tam Dao mountains), possibly southern China. It is known only from two small areas, but its exact distribution is unknown and may be larger than currently known. Habitat:  Steep rocky limestone cliffs in primary evergreen rainforest, 800-1300 m asl., near running water. Also found in rocky crevices along brooks and in accumulated water in old, abandoned buildings. Food:  Insects and other small animals. Reproduction:  Breeds in accumulated still water in rocky cavities. Unlike other bug-eyed frogs, the Tonkin Bug-eyed Frog is monogamous (breeds in pairs), and calling males and pairs in amplexus (mating position) have mainly been observed in April-June, occasionally with several pairs at the same site. 6-17 large, hard-shelled eggs are laid in a foam nest hanging on the cliff side over the water. Sometimes as many as 5 clutches are laid (up to 60 eggs in total) with intervals of 10-15 days. When the tadpoles have developed, they are washed down into the water by the the rain. Here they live until the transformation into little frogs is completed. Activity and behaviour:  Nocturnal. Enemies:  When disturbed, the frog shuts its eyes, arches the back and curls up in its typical defense posture, where it resembles a fir cone rather than a frog. Sexual differences:  Females attain a slightly larger size than males (see above). Status:  The distribution of the species has not been thoroughly investigated, but since it is only known from two restricted areas of which it has not been recorded since 1930 in one of them, it may be vulnerable, although it appears to be locally common at the one site where it has been observed in recent years. Both Tam Dao and Mao Son populations are threatened by habitat loss. As one of the few species of the region, the frog is also in demand by the global pet trade. Notes:  The camouflage of the Tonkin Bug-eyed Frog is remarkable. Even experienced field biologist report how difficult it is to find in the wild. Apparently it is easiest to find at night where the light from a torch will reflect in the eyes of the frog and thereby reveal its presence. References: Birdlife International. 2001. Sourcebook of existing and proposed protected areas in Vietnam. www.wing-wbsj.or.jp/~vietnam Bourret, R. 1942. Les Batraciens de l'Indochine. Institut Oceanographique de l'Indochine. 547 pp. Inger, R.F.; Orlov, N. & Darevsky, I.S. 1999. Frogs of Vietnam: a report on new collections. Fieldiana Zoology 92: 1-46. IUCN, Conservation International, and NatureServe. 2004. Global Amphibian Assessment. (set 22 December 2006). www.globalamphibians.org McRae, M. 1999. Tam Dao - Vietnam's sanctuary under siege. National Geographic 195(6): 82-97. Obst, F.J.; Richter, K. & Jacob, U. 1984. Lexicon der Terraristik. Landbuch, Hannover. 465 pp. Orlov, N.L. 1997. Die Theloderma-Arten Vietnams. Herpetofauna (Weinstadt) 19(110): 5-9. Text & layout: Rune Midtgaard

Gallery Home It is not hard to imagine how difficult it must be to find the Tonkin Bug-eyed Frog in the wild. Sitting on a piece of moss, it is almost impossible to see. © Rune Midtgaard.