Enterobius (Colobenterobius) colobis Vuylstéke, 1964 (Nematoda: Oxyuridae) is redescribed based on males and females collected from an ashy red colobus, Procolobus rufomitratus tephrosceles (Elliot, 1907) (Primates: Cercopithecidae: Colobinae), in Uganda. Two morphotypes are recognized among females, which are readily distinguished by tail length, termination level of lateral alae, and egg size. The relative position of cellular wall greatly varied in the ovijector, indicating its limited systematic value. The males possess a much shorter spicule than those in previous descriptions, suggesting the presence of polymorphism.