A Variational Analysis of Populations of Bothrops (Serpentes: Viperidae) from Western Venezuela

Character variation was analyzed with univariate and multivariate methods in populations of Bothrops from the Andean piedmont (N = 37) and nearby upper Ilanos (N = 19) communities of western Venezuela in an area of suspected sympatry between Bothrops atrox and B. asper. In an atrox-asper affinity gradient created with four currently-used specific diagnostic characters, 80% of the specimens were intermediate, and no character suite or single character separated the snakes into two discrete taxonomic units. Specimens from these populations represent one species, B. atrox, rather than two sympatric ones. Character variation in these populations is complex, and a summary table of sexual, ontogenetic, and geographical relations to variation of 13 characters is presented