Checkered Keelback

1 Overview

The Checkered Keelback, alias 渔蛇 and 草花蛇, is very common in China. It mainly inhabits uninhabited places such as hills, fields, rivers, and lakes. It is quite aggressive and often attacks unprepared snake-catchers. When startled it rears up the front of its body into a striking posture.

Chinese Name: Checkered Keelback (渔游蛇)

Chinese Alias: 渔蛇, 草花蛇

English Name: Checkered Keelback

Binomial: Xenochrophis piscator

Kingdom: Animalia

Phylum: Chordata

Class: Reptilia

Order: Squamata

Suborder: Serpentes

Family: Natricidae (formerly placed in Colubridae)

Genus: Xenochrophis

Species: Xenochrophis piscator

Distribution: Southern and southeastern Asia — from Afghanistan, Pakistan, and Sri Lanka eastward through Indochina, south via the Malay Peninsula to Indonesia, and Taiwan, as well as mainland China (Jiangsu, Zhejiang, Anhui, Fujian, Jiangxi, Hubei, Hunan, Guangdong, Hong Kong, Hainan, Guangxi, Guizhou, Yunnan, Xizang/Tibet, Shaanxi). Semi-aquatic in habit.

2 Physical Characteristics

Its body color is highly variable; common dorsal colors include gray-brown, olive-green, yellow-brown, or orange. It is not large, with a total length of about 0.8 m.

The head is long-elliptical and clearly distinct from the neck. From the nape to the tail there are black net-like markings with prominent black blotches on either side; the pupil is round; the front of the snout scale is narrow, with nostrils dorsolaterally placed. The top of the head is gray-green, with a short black line from below the eye to the lip and a long black line from behind the eye to the mouth corner; the neck bears a V-shaped black mark. The underside is white, yellowish-white, or pale green-yellow, with black bases on the ventral scales producing evenly spaced black cross-bands across the belly.

Note: the so-called ‘red-spotted checkered keelback’ is actually a red phenotypic variant of the yellow-spotted form.

3 Habitat and Behavior

A semi-aquatic cold-blooded animal, a newly purchased individual may be stressed by the new environment and unfamiliar people; give it time to adjust and its temperament will improve as it settles in.

It inhabits the banks of rivers, lakes, and ponds in hills, plains, and fields. Nocturnal and able to dive and swim underwater, it is water-leaning but still needs land. In captivity a large water basin and a hiding cave are essential. This snake has a bad temper — beware of bites — though it calms once familiar. Hiding caves can be bought or DIY-built; the basin is for soaking.

4 Husbandry and Breeding

Naturally fierce and in the wild quick to attack snake-catchers, a captive individual becomes gentler once acclimated. Do not co-house it with other snake species.

When startled it rears the front of its body into a striking posture. It lays eggs from May to July, 3–14 per clutch, naturally incubated over a little more than one month. Its main prey is small fish, supplemented by frogs and toads; in captivity it will also eat fish and frogs, as well as loaches. It only takes live food, so keeping feeder fish in the same water lets it hunt them itself.