Identification
This species possesses keeled scales. Head is broader than the neck and eyes are with round pupils. Two black bold streaks are visible one after another from eyes to mouth.Glossy olive green, olive brown, yellow, brown, gray or black body colorations usually with a checkered body pattern which brought it the name “Checkered keelback”. Pattern may vary in coloration from pale to bold and closely set spots or checks. Space between checks sometimes marked with different shades of pink and red. It is very aggressive in nature and bite with full force when provoked. Some times to check its surroundings, it lifts its head above base.
Length: 2ft to maximum 6.75 ft.
Scalation
Scales in 19 rows at midboody. Ventrals 122-158; anal usually divided; subcaudals (60) 70-97, paired. Internasals distinctly narrowed anteriorly. Supralabials 9 (4th and 5th touching eye, 6thexcluded by lowest postocular); preoclar 1; postoculars 3; temporal 2+2 or 2+3.
Habitat and Reproduction
They are found in freshwater bodies and paddy fields. Feed on frogs eggs, tadpoles, and water insects; older snakes eat fish, frogs and rats. Usually mating is done after mid summers but mating behavior is observed at the end of monsoon. It is oviparous and lay eggs in December-March in shades, barks etc. Clutch size can be 90 and female stays with them until they hatch after 60-70 days.
Bite and venom
They bite readily after caught. They are aggressive when cornered and threatened. When threatened it flattens head and inflates neck ribs to deter threat.
Distribution:
It is recorded from entire India and Southeast Asia except Andaman & Nicobar Island and higher altitudinal areas of India. It was the second most common snake after Indian Rat snake, that distributed throughout Chhattisgarh. The species can be usually seen near wet surfaces, river or pond sides.
Threats:
Lack of awareness and its aggressive nature make it vulnerable to killings by human. Though this species is abundant in human dominated areas but wetland acquisition for developmental works gradually destructs their habitats.