First name: Emma
Last name: Taylor
Class Year: 2026
Advisor: Eric Sargis
Essay Abstract:
The guenons (tribe Cercopithecini) are a diverse group African Old World monkeys (Primates, Cercopithecidae) comprising six genera. Chlorocebus dryas is an endangered species with a restricted distribution in the forests of the Democratic Republic of Congo. Although originally classified within Cercopithecus, genomic evidence indicates a closer relationship with Chlorocebus. However, previous assessments have noted the unique craniodental morphology of Ch. dryas relative to other Chlorocebus species. Using a combination of quantitative craniodental measurements and qualitative morphological characters, two recently recovered Chlorocebus dryas skeletal specimens (YPM MAM 16890 and YPM MAM 17066) were compared to multiple species within the genera Cercopithecus and Chlorocebus to further evaluate the morphological distinctiveness of Ch. dryas. Analyses of linear measurements, derived indices, and discrete cranial and mandibular features reveal that Ch. dryas differs significantly from other Chlorocebus species while sharing some similarities with Cercopithecus. However, genetic evidence precludes the placement of Ch. dryas within this latter genus. Instead, Ch. dryas exhibits a unique combination of traits, supporting its recognition as a distinct genus. This taxonomic revision has important implications for understanding guenon evolution and reinforces the conservation significance of this species.