The Amazonian slopes of the Andes in Colombia, Ecuador, Peru, and Bolivia, eastward across the upper portion of the Amazon Basin to the Guiana highlands and the upper Orinoco region from eastern Colombia through southern Venezuela eastward including Guyana, Suriname, and French Guiana, as well as most of Brazil north of the Amazon in the states of Amazonas, Roraima, Rondonia, and Amapá. It occurs on both sides of the Amazon in Pará (Brazil).
Type: Destroyed, formerly at MSNG according to golay et al., 1993, Endogly. Venom. Snakes World 478pp.[170].
Type-locality: Colombia
Two subspecies, namely M. h. hemprichii (Jan, 1858) and M. h. ortoni Schmidt, 1953, were recognized by Roze, 1983.
