Material Examined : 6 speciemens, including 2 juveniles and 4 sub-adults.

Description & Scalation : Body cylindrical, elongate. Head small barely distinct from neck. Eye small with vertical pupil; Nostril in the nasal; frontal much broader than the supraocular; 1 loreal not in contact with internasal. 1 pre-, 1 post- and 1 subocular; 1 long anterior temporal. Scales smooth and subequal, in 19:19:17 rows; supralabials 5 ( 3rd and 4th below the eye, but not in contact, 4th and 5th largest ); infralabials 8-10, first 3-4 touching the first pair of genials; ventrals 246–262, well developed; subcaudals 53-66, paired; tail moderate, slightly compressed, tail tip blunt; anal divided.

Coloration : Juveniles are black or dark gray above with 57-66 distinct lemon-yellow transverse bands encircling the body and 13-19 on the tail, these bands widen towards the belly. Adults are dark gray or brownish above, with dull indistinct yellow bands or blotches, belly blackish-gray or with distinct lemon-yellow bands. Two pale yellow bands on head, lip scales blackish-brown, with yellow blotches.

Natural History : A groove-fanged snake, nocturnal in habits. Mainly found on undisturbed mud-flats in mangrove marshes, at low tide. 2 juveniles were obsereved on knee deep mud-flat at about 2200 hrs in Middle Andaman, with their tails inside crab holes and about 6m apart from each other. 14 adult speciemens were encountered in thigh deep mangrove mud, at about 2130 hrs in North Andaman, with their posterior half inside crab holes and about 8 to 10m apart from each other. Four larger ones ( approx 1.5m total length ) were observed in waist deep mangrove mud and were in pairs. This species occurs in the same geographical areas where other species such as Cerberus rynchops ( Dog-faced water snake ) and Gerarda prevostiana ( Glossy Marsh snake ) also occur and this swampy area has thousands of mosquitoes. Feeds during low tide and on open mudflat when it is easy to catch crabs and small fish stranded in small pools and shallow run-off streams. Said to be venomous in the Andamans, several Karens ( immigrants from Myanmar) claim that of the two people who had been bitten by this snake, one died while the other remained unconscious for 2-3 days. Symptoms mentioned by them include acute abdominal pain, vomiting blood and swelling at the site of the bite. Nothing is known of its reproductive biology. Grows up to 1.5m.

Distribution - India : Andaman Islands, possibly Nicobar Islands. Elsewhere : Much of southeast Asia.

External link : http://reptile-database.reptarium.cz/species?genus=Cantoria&species=violacea