Lachesis (genus)

The bushmaster (Lachesis muta) is a venomous snake of the viper family. The bushmaster inhabits forested areas and adjacent clearings of South America. Adults range in length from two to 2½ metres (seven to eight feet) and some individuals may reach three metres (10 ft). The largest known adult was just under 3.65m (12'), making the bushmaster the longest venomous snake in the Western Hemisphere. The bushmaster is also the longest viper, though not the heaviest (it is surpassed by the Gaboon viper and the Eastern Diamondbask rattlesnake). Bushmasters feed exclusively on small mammals, and, despite their size, feed on smaller animals than other snakes.

The bushmaster is the only neo-tropical pit viper that lays eggs, about a dozen in the average clutch. The female is reported to remain with the eggs during incubation and may aggressively defend the nest if approached. The hatchings average 30 cm (20 in.) in length and are more colorful than the adults.

Subspecies of the bushmaster include:

• Lachesis muta muta - the nominate race that inhabits Ecuador, Peru and northern Brazil.
• Lachesis muta stenophrys - darker colored, lives in Panama and Costa Rica.
• Lachesis muta rhombeata - eastern Brazil.
• Lachesis muta melanocephala - southwestern Costa Rica

The subspecies L. m. stenophrys and L. m. melanocephala are sometimes elevated to the rank of species.

The bushmaster's bite can be fatal for humans, causing massive internal bleeding and tissue necrosis (death of cells). Even treated, the mortality rate is 80%. Nonetheless, bushmasters are not often seen as they inhabit deep forest. Their lethality seems to have influenced their collective scientific naming however. Lachesis muta means mute fate, a testament to the inevitablity of death to a bitten individual.

Reference

• Living Snakes of the World in Color by John M. Mehrtens, 1987. ISBN 0-8069-6460X