Porthidium is a genus of pit vipers found in Mexico and southward to northern South America.

[1] The name is derived from the Greek word portheo and the suffix -idus, which mean "destroy" and "having the nature of", apparently a reference to the venom.

All have a sharply defined canthus rostralis and a rostral scale that is higher than it is broad.

[2] Found in Mexico (Colima, Oaxaca and Chiapas on the Pacific side, the Yucatán Peninsula on the Atlantic side) southward through Central America to northern South America (Ecuador in the Pacific lowlands, northern Venezuela in the Atlantic lowlands).

[1] Nota bene: A binomial authority in parentheses indicates that the species was originally described in a genus other than Porthidium.