Taxonomic comments from Anthony Rylands on selected great apes:

Bwindi Gorilla – Gorilla beringei ssp.

Gorillas from the Bwindi Impenetrable National Park are considered by some to be a third distinct form of eastern gorilla, but this has yet to be made official with, as a subspecies, a formal latin trinomial. Reference: Sarmiento, E. E., Butynski, T. M. and Kalina, K. 1995. Taxonomic status of the gorillas of the Bwindi Impenetrable Forest, Uganda. Primate Conservation (16): 40–43.

Eastern Chimpanzee – Pan troglodytes schweinfurthii

Groves (2005) carried out a study of the morphology of the eastern chimpanzees and concluded that the populations currently considered to be Pan troglodytes schweinfurthii (Giglioli, 1872) de facto comprise two distinct forms: P. t. schweinfurthii, the larger, in the northwest, type locality Niam-Niam country, upper Uele; and P. t. marungensis (Noack, 1887), the smaller, in the Rutshuru district to western Uganda, south to Rwanda, Burundi and northwestern Tanzania, type locality Marungu, west of Lake Tanganyika. Reference: Groves, C. P. 2005. Geographic variation within eastern chimpanzees (Pan troglodytes cf. schweinfurthii Giglioli, 1872). Australasian Primatology 17: 19–46.

Northeast Bornean Orangutan – Pongo pygmaeus morio

Recognized by Groves (2001). Not recognized by Brandon-Jones et al. (2004) who concluded that “Simia morio Owen, 1837 and other synonyms Groves (2001a) applied to this population almost certainly all pertain to P. p. pygmaeus.” (p.154). It is listed here because it was specifically named in reference to the identification of priority areas in a workshop held under the auspices of the IUCN/SCC Primate Specialist Group to develop an action plan for orangutans (Berastagi, North Sumatra, September 2005). The problem would appear to be merely nomenclatural in that Brandon-Jones et al. (2004) do list a “P. pygmaeus population from Indonesia (E. Kalimantan, south to the Mahakam River), Malaysia (Sabah)”, which they say has skulls similar to those of P. p. pygmaeus but are very small, and indicate that it might may be a distinct and as yet unnamed subspecies. References: Brandon-Jones, D., Eudey, A. A., Geissmann, T., Groves, C. P., Melnick, D. J., Morales, J. C., Shekelle, M. and Stewart, C.-B. 2004. Asian primate classification. International Journal of Primatology 25(1): 97–164. Groves, C. P. 2001. Primate Taxonomy. Smithsonian Institution Press, Washington, DC.