What type of creature is a fer-de-lance?

The fer-de-lance is one of several extremely venomous snakes of the viper family ("Viperidae") found in diverse habitats from cultivated lands to forests throughout tropical America and tropical Asia. The fer-de-lance, known in Spanish as "barba amarilla" (“yellow chin”), is a pit viper - i.e., distinguished by a small sensory pit between each eye and nostril. It has a broad triangular head and is usually about 1.2 to 2 metres (4 to 7 feet) long. It is gray or brown, marked by a series of black-edged diamonds often bordered in a lighter colour. Its bite can be fatal to humans.

The common French name fer-de-lance, or “lance head,” originally referred to the Martinique lancehead ("Bothrops lanceolatus") found on the island of the same name in the West Indies. The name fer-de-lance has also been used collectively to describe all snakes of the Central and South American genus "Bothrops" and the Asian genus "Trimeresurus". Among these snakes, all venomous, are the habus and related species, such as Wagler’s pit viper; the jararaca ; the wutu, or urutu; and the jumping viper, or tommygoff.

The snake is helpful with pest control for farmers and the venom shows promising uses as a medicine or drug. There are many studies of the physiological effects of the venom on victims as well as reported research of a possible medicinal use of the venom.