Species of the genus are found in China, Japan, Taiwan, and northern Vietnam.

[1][3] Achalinus was previously placed in Colubridae (along with other xenodermids).

[4] The nickname "odd-scaled" is because their dorsal scales do not overlap one another as in most snakes, but instead are spread out and lie individually similar to pieces of a puzzle.

Odd-scaled snakes are known to be burrowers that crawl below the fallen leaves of the forest.

Nota bene: A taxon author (binomial authority) in parentheses indicates that the species was originally described in a genus other than Achalinus.