The banding karyotypes of six of the eight taxa recognized for the Bufo spinulosus species group in Peru are described herein. All specimens exhibited 2 n = 22 chromosomes (n = 11 bivalents). The six morpho-taxa correspond to only three karyomorphs: “spinulosus”, “limensis” and “cophotis”, the first two being more closely related to each other than they are to cophotis. It is estimated that each karyomorph possesses sufficient attributes to be considered as full species. A cladistic analysis was made and a new classification for the species of the spinulosus group that inhabit Peru, is proposed.