We report the proteomic characterization and biological activities of the venom of the black-speckled palm pitviper, Bothriechis nigroviridis, a neotropical arboreal pitviper from Costa Rica. In marked contrast to other Bothriechis species investigated, the venom of B. nigroviridis does not possess detectable Zn(2+)-dependent metalloproteinases, and is uniquely characterized by a high content of crotoxin-like PLA(2) and vasoactive peptides. These data suggest that different evolutionary solutions have evolved within the arboreal genus Bothriechis for the same trophic purpose. The venom from B. nigroviridis is devoid of hemorrhagic activity, has low edematogenic and coagulant effects, presents modest myotoxic and phospholipase A(2) activities, but has higher lethality than the venoms of other Bothriechis species. Neutralization of its lethal activity by an anti-Crotalus durissus terrificus antivenom confirmed the major role of crotoxin-like PLA(2) in B. nigroviridis venom-induced lethality.