Alsophis is a genus of snakes in the Colubridae family. They are among those snakes called “racers” and occur throughout the Caribbean. One species in the genus Alsophis, the Antiguan Racer (Alsophis antiguae), may be the world’s rarest snake and is currently critically endangered, though in the last 15 years, conservation efforts have boosted numbers from an estimated 50 to some 500 snakes.
These snakes are rear fanged, but they are small in size (females grow to around a meter in length) and are considered harmless to people. This genus contains at least fourteen described species, with at least one extinct species - the Saint Croix Racer (Borikenophis sanctaecrucis) which was endemic to the U.S. Virgin Islands. The Hispaniolan racer (Alsophis melanichnus) is possibly also extinct, though it’s IUCN status is currently “not evaluated”.
The two snakes shown above are the Antiguan Racer (top) and Antilles Racer (Alsophis antillensis) (bottom).