Family Calamariidae consists 6 genera 96 species. They occurred from India, Southeast Asia, southern China to Japan. The body size of the snakes are small (with ±30 cm in length). Some of the snakes (e.g., Calamaria, Calamorhabdium) burrow and feed on worms.
We estimated the emergence of Calamariidae at ~33 Mya using fossil calibrations.