It seems that Bothrops Asper and Bothrops Atrox and Bothrops Lanceolatus are all mixed up. Bothrops Lanceolatus "the real Fer de lance", is only found on the island of St. Martinique.
The books "Poisonous Snakes of the World" lists Bothrops Asper or Tommy Goff, while "Venomous Snakes of World" lists Bothrops Atrox or Tommy Goff, Barba Amarilla. The Wildlife Conservation Society lists Fer-de-lance as Bothrops Asper, and a well planned websight called Caske 2000, which has done great reports on Belize adventures, lists Fer de lance (Bothrops Asper) as well.
To make matters worse, The Wildlife Conservation Society lists yet another snake, the False Fer-de-lance or Xenodon Rabdocephalus.
For starters, I would think the same occurs in Belize, as occurs in the states. If it is yellow, it is a Copperhead. If it is near water, it is a Water Moccasin. If it rattles, it is a Rattlesnake. At my parents farm, I looked for snakes for 15 years (I like them). We had 40 acres which included a few 2 acre ponds and we were surrounded by farms. We had some big snakes, but none that we could prove dangerous. I have seen many snakes of different colors and of very large size, and I have seen a 5 foot long (rat snake?) on a tree rattling his tail like crazy. But one orange snake goes into the neighbors garage and it is a copperhead. You get my point. It was a FER DE LANCE!!!!
*Note- After all these years I found my first Copperhead (I checked the fangs, and sick dog).
So what to do now? I just assume that the antevenoms are similar or collected/produced regionly to insure the effectiveness of snakebite treatments.
Szg Docent Bulletin board
The Fer-de-lance (Bothrops atrox now B. asper) is another infamous pit viper of Latin America. If startled or provoked, it is quite aggressive and bites vigorously and often repeatedly. It is responsible for more fatalities in its range than any other species. As it strikes, it often leaves the ground. It's name describes its lance-shaped head and was first applied to a relative on Martinique Island that looks similar but is now nearly extinct B. lanceolatus. A nocturnal snake, it eats small mammals and ground dwelling birds, capturing them by lying in wait, perfectly camouflaged in the undergrowth. The snakes average 1.2-1.8m, record length 2.4m. They are highly prolific, a mother giving live birth to about 50-70 at a time. New-borns are 25-30cm long and highly venomous. Younger snakes are found near streams feeding on frogs and large insects.
Written by Jason Degroot, Michigan State University student
The common lancehead is often mistakenly referred as the fer-de-lance. The local name for this snake is the Barba amarilla. The true fer-de-lance lives in the West Indies (Mattison, 1986). Mattison, Chris. 1986. Snakes of the World. Blandford Press, United Kingdom.
The lancehead is a hunter that relies on its camouflage to attack prey. The skin color blends in perfectly with the surroundings. Using the pit organs, it can deduce the position of its prey. This snake has also been known to be very aggressive. Conflicts with people have occurred due to its habit of lying in walking trails in wait of prey as well as invading plantations in search of rodent prey (Mattison, 1986).