Banded Stream Snake (non-venomous)

Description: The largest of local Opisthotropis species, reaching a total length of 105 cm or more. Ground colour yellow or orange-yellow, with at least 40 pairs of black bands with yellow centres encircling the body. First pair of black bands extends onto rear of head. Scales moderately keeled. Top of head mottled with black. Upper and lower labials marked with black. Also a conspicuous black mark beneath each eye. Tip of snout rounded. Nostrils open on top of snout.

Habits and habitat: Inhabits large, rocky, unpolluted streams at low to moderate altitude. Seems to be diurnal, unlike the other three Hong Kong Opisthotropis species. A gentle and quiet snake; when caught, never attempts to bite. Little else is known of its habits. Occasionally sympatric with Opisthotropis lateralis.

Diet: Details of natural diet unknown. One captive specimen took small fish.

Reproduction: Nothing is known of its local breeding habits. One hatchling measured 13 cm.

Distribution: A rare snake in Hong Kong. Currently only ten local specimens have been documented. First recorded in 1978 from Shuen Wan in the north-east New Territories, and in 1982 from Ping Shan Chai in the Pat Sin Range. Has since been recorded from Bride¡¦s Pool, the vicinity of Tai Long Wan in eastern Sai Kung, Wong Chuk Yeung near Ma On Shan, Sha Tau Kok and lam Tsuen River. Found in southern China, Cambodia and Vietnam.

Diagnostic features: Body encircled by black and yellow bands, alternating with each other; black bands split dorsally by a thin, yellow, transverse line.