King ratsnake  (Elaphe carinata)

This species has not yet been classified by the IUCN.

The king ratsnake is a large, impressive, heavy-bodied constrictor known by several curious common names; the ‘ratsnake’ refers to its habit of eating other snakes, the ‘keeled ratsnake’ to its heavily keeled scales that give the skin a rough texture; and ‘stinking goddess’ to the distinctive habit of releasing a strong, offensive odour from post-anal glands when handled or otherwise threatened (3) (4). This snake undergoes a rather radical colour transformation from relatively non-descript tan-coloured juveniles into dark brown or black adults with a striking pattern of bright yellow highlights (3) (5). A tear-drop shaped pupil distinguishes this snake from any other Elaphe species (3).

Three subspecies are recognised: E. c. carinata is found throughout most of China and northern Vietnam; E. c. yonaguniensis is found on the island of Taiwan and the Ryukyu Islands of Japan; and E. c. deqenensis is known from only a few specimens found in Northwest Yunnan province, China (2).

A largely terrestrial species known to inhabit open forests, fields, meadows and bamboo thickets, although it has also been collected near houses (2) (4).

Very little is known of this snake in the wild, but as a popular pet, much is documented on its habits in captivity. The diet includes rodents, birds, bird eggs and other snakes, and this species is even known to have cannibalistic tendencies towards its own kind (2)!

Mating usually occurs in spring, with six to 12 eggs being laid in early to mid-summer, which then take a following 40 to 60 days incubation before hatching (2).

Despite its habit of releasing foul odours, the king ratsnake makes a surprisingly popular pet, and capture for the pet trade probably poses the greatest threat to wild populations. In 1997, 37,425 king ratsnakes were imported to the United States. As such, this snake was the fifth most imported reptile species and represented an incredible 2.2 percent of all reptile imports for that year. China was the main country of origin, exporting a total of 37,412 king ratsnakes that year (4). This snake has also been collected from the wild to be used in ‘traditional Chinese medicine’ (6), and habitat loss may pose an additional threat.

There are currently no known conservation measures targeting this species.

View information on this species at the UNEP World Conservation Monitoring Centre.