Venomous snakes in Costa Rica

Part of the important research work at the Clodomiro Picado Institute consists of the identification of the species of venomous snakes found in the country. Its purpose is to know the characteristics and composition of their venom, which will help develop antiophidic or antivenom serums to treat the effects of snakebites.

Reptiles are a very diverse group; in Costa Rica snakes represent about two thirds of this group. Eleven families of snakes have been identified, among which only two are considered “possibly lethal” to humans. Thus, from 140 species found in Costa Rica, only 23 species are considered venomous. 

These species of venomous snakes are divided in two large families: Elapidae and Viperidae. The Elapidae family includes a species of sea snake, Hydrophis platurus, and five species of venomous coral snakes of the Micrurus sp. genus. While in the Viperidae family, 23 species in 8 genera are identified (Agkistrodon, Atropoides, Bothriechis, Bothrops, Cerrophidion, Crotalus, Lachesis, Porthidium). Some of the main differences of these venomous snakes are the presence of a loreal pit (special structures capable of perceiving heat) in montane pitvipers (Viperidae), their particular “triangle” shaped head and the rough appearance of their scales. 

Venomous coral snakes (Elapidae) have a red - yellow (white) - black - yellow (white) color pattern on their whole body, their colors are bright, and they are relatively small and thin. Furthermore, their venoms have different effects: coral snakes cause envenomings with neurotoxic effects, while montane pitvipers cause mainly myotoxic envenoming (affects the muscle), and hemotoxic (causes hemorrhage), in an ophidic accident.

The Institute has compiled plenty of information about snakes in the country, which has facilitated the technological development of antivenoms and has generated the experience to assess and support other entities around the world. 

The venomous snakes currently found in Costa Rica are introduced next: