Erycines are those snakes in the subfamily Erycinae of the family Boidae. Therefore they are in the same family with the other Boas and Pythons. However, unlike some of the other Boids, Erycines are small snakes. The largest species is probably the Indian Sand Boa at slightly under 4 feet (1.2 m.) in length, while the Arabian Sand Boa rarely exceeds 16 inches (40 cm.).
The Erycinae includes the Old World Sand Boas (genus Eryx), the North American Rosy Boas (genus Lichanura), the North American Rubber Boa (genus Charina), and sometimes includes the African Burrowing "Python" (genus Calabaria). See the taxonomy and systematics page for further discussion of these relationships.