Metlapilcoatlus mexicanus

Metlapilcoatlus mexicanus is a venomous pitviper species endemic to Mexico and Central America.
Description.
 Adults grow to an average of 50–70 cm (about 20-28 inches) in total length. The maximum total length is for males and for females. The body is extremely stout.
Geographic range.
Found in the Atlantic drainage from Mexico (in the Mexican states of Tabasco and Chiapas) south to the Canal Zone in Panama, both slopes of Costa Rica and Panama. Occurs at elevations of . The type locality given is "Coban, capitale de la province de la Véra-Paz, (République de Guatemala, Amérique centrale)" (Cobán, Alta Verapaz, Guatemala).
Taxonomy.
Regarded as a full species, "Metlapilcoatlus mexicanus", by Campbell and Lamar (2004).