Maxwell's Mountain Keelback

Opisthotropis maxwelli may attain a total length (tail included) of 44 cm (17 in). The tail is rather long, comprising 20–23% of the total length. The dorsal scales are keeled, more strongly so on the posterior of the body, and arranged in 17 rows throughout the length of the body. Dorsally, it is dark olive; ventrally, it is yellow.

Opisthotropis maxwelli is found in southeastern China, in the provinces of Fujian, Guangdong, and Jiangxi, and the autonomous region of Guangxi.

Opisthotropis maxwelli preys predominately upon aquatic segmented worms, and also freshwater shrimp, fishes, frogs and their tadpoles.

The specific name, maxwelli, is in honour of British Presbyterian missionary John Preston Maxwell (1871–1961), who also was a physician working in China (1898–1936), and who presented the holotype to the British Museum (Natural History).