Terciopelo (also known as Fer-de-lance)
Bothrops asper • Order: Squamata, Suborder: Serpentes, Family: Viperidae, Subfamily: Crotalinae, Genus: Bothrops, Species: B. asper
Widespread throughout the humid lowlands of southern Mexico, Central America, and northwestern South America (Colombia and Ecuador).
Look up Terciopelo (also known as Fer-de-lance) in the Snake Encyclopedia →Venomous Status
Venomous (Solenoglyphous - large, hinged, hollow front fangs).
Danger Level
Extremely Dangerous. This species is responsible for the majority of serious snakebite cases and fatalities within its geographic range due to its size, proximity to human habitats, and reactive nature.
Family
Order: Squamata, Suborder: Serpentes, Family: Viperidae, Subfamily: Crotalinae, Genus: Bothrops, Species: B. asper
Conservation
Least Concern (IUCN). Despite being persecuted by humans, the species is highly adaptable to human-altered landscapes and remains abundant.
Physical Description
Heavy-bodied pit viper with a distinctively triangular 'lance-shaped' head and a sharp canthus rostralis. The dorsal pattern consists of a series of dark brown, pale-edged triangles or 'diamonds' on each side (often meeting at the spine to form 'X' shapes). It has vertical elliptical pupils, loreal pits, and heavily keeled scales. Coloration is typically brown, olive, or gray.
Size & Dimensions
Specimen pictured appears to be a juvenile or sub-adult based on body proportions. Adults typically range from 1.2 to 1.8 meters (4–6 feet), but large females can exceed 2.5 meters (8 feet).
Habitat
Inhabits tropical rainforests and evergreen forests, often near water or in disturbed areas such as agricultural plantations. Found from sea level to approximately 1,200 meters elevation; highly terrestrial but can be found in low vegetation.
Behavior & Temperament
Highly defensive and easily agitated. When threatened, it often coils and strikes rapidly. It is primarily nocturnal, spending days camouflaged in leaf litter, which leads to accidental encounters with farmworkers or hikers.
Diet & Feeding
Generalist predator. Juveniles often feed on small lizards, frogs, and invertebrates (frequently using caudal luring). Adults primarily hunt small mammals (rodents) and birds using ambush tactics.
Reproduction
Viviparous (gives birth to live young). It is one of the most prolific vipers, with litters ranging from 20 to 100 individuals. Breeding occurs year-round but peaks with the rainy season.
Venom Profile
Highly complex hemotoxic, cytotoxic, and myotoxic venom. It causes severe local tissue destruction (necrosis), systemic hemorrhaging, and coagulopathy.
Look-alikes
Often confused with other Bothrops species (like B. atrox, though ranges mostly don't overlap) or the harmless Neotropical Bird Snake (Pseustes poecilonotus) and False Fer-de-Lance (Xenodon rabdocephalus), which mimic its pattern.
Conservation Status
Least Concern (IUCN). Despite being persecuted by humans, the species is highly adaptable to human-altered landscapes and remains abundant.
Cultural Significance
Highly significant in Latin America as the most feared snake due to its medical impact. It plays a vital role in ecosystem balance by controlling rodent populations in agricultural areas.
Notable Features
Features a highly distinct 'canthus' (the ridge between the eye and snout) and spectacular camouflage that makes it nearly invisible in forest floor leaf litter.