ECUADORIAN PIT-VIPERS OF THE GENERA BOTHR IECHIS, BOTHROPS AND PORTHIDIUM

This study compiles the morphological data of more than 500 specimens of crotalid snakes from Ecuador including some type material. Thirteen species and two subspecies are assigned to three genera, i. e. Bothri echis Peters (bilineatus smaragdinus, oligolepis albocarinatus, p. pun ctatus, p. mahnerti, schlegelii, taeniatus), Bothrops Wagler (atrox at rox, atrox xanthogrammus, brazili, lojanus) and Porthidium Cope (almaw ebi n. sp., hyoprora, lansbergii arcosae n. ssp., microphthalmum and n asutum). Bothrops lojanus Parker, Bothriechis p. mahnerti and Porthidi um l. arcosae are endemic. Bothrops osbornei Freire is identical with Bothriechis p. mahnerti Schatti & Kramer. Bothrops peruvianus (Bouleng er) and B. albocarinatus Shreve are considered to be conspecific with Bothriechis oligolepis (Werner). This species is polytypic, including the nominate subspecies and B. o. albocarinatus from Amazonian Ecuador and Peru. The type of Trigonocephalus pulcher Peters belongs to Bothr iechis o. albocarinatus. The form commonly assigned to 'Bothrops pulch er' auct. is described as Porthidium almawebi n. sp. The generic alloc ation of this new species accounts for morphological evidence and beha viour. Trigonocephalus asper Garman is a synonym of Bothrops atrox (L. ). Bothrops xanthogrammus Cope from western Ecuador and the Pacific sl opes of Colombia represents a subspecies of atrox, if these forms are not identical. Lachesis pleuroxanthus Boulenger might represent a vali d species. The systematic arrangement of the Ecuadorian species is dis cussed.