Order: Artiodacyla* (even-toed hoofed animals: includes pigs, sheep goats, cattle, deer)
Species: Hippopotamus amphibius - common hippopotamus
Species: Choeropsis liberiensis - pygmy hippopotamus
*Anatomical and DNA evidence on the relationship between Artiodactyla (even-toed ungulates) and Cetacea (whales and dolphins) led to a merging of the two orders into a new group, Cetartiodactyla (Montgelard, 1997; reviewed in Kulemzina, 2009). As of October 2012, experts had not agreed on whether to define Cetartiodactyla as an official taxonomic order that would replace Artiodactyla and Cetacea. Some continue to list hippopotamuses in the order Artiodactyla (Franklin, 2011) or use the term Cetartiodactyla without defining it as an order (IUCN, 2008).
Describer (Date): Linnaeus (1758) Systema Naturae Tenth ed. Vol 1. p 74, Laurentii Salvii Stockholm. Described animals from the Nile River in Egypt.
Boisserie et al. (2005)
Harris et al. (2008)
Lihoreau et al. (2006)
Meester & Setzer (1971)
Wilson & Reeder (1992)