Eosimias

Eosimias Temporal range: 45–35 Ma PreꞒ Ꞓ O S D C P T J K Pg N Middle Eocene - Late Eocene[1]
Restoration of E. sinensis
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Primates
Suborder:	Haplorhini
Infraorder:	Simiiformes
Family:	†Eosimiidae
Genus:	†Eosimias Beard et al., 1994
Species[1]
†Eosimias centennicus (Beard et al. 1996) †Eosimias dawsonae (Beard and Wang 2004) †Eosimias sinensis (Beard et al. 1994) †Eosimias paukkaungensis (?) (Takai et al. 2005)[2]

Eosimias is a genus of early primates, first discovered and identified in 1999 from fossils collected in the Shanghuang fissure-fillings of Liyang, the southern city of Jiangsu Province, China. It is a part of the family Eosimiidae, and includes three known species: Eosimias sinensis, Eosimias centennicus, and Eosimias dawsonae.^[3] It provides us with a glimpse of a primate skeleton similar to that of the common ancestor of the Haplorhini (including all simians). The name Eosimias is designed to mean "dawn monkey", from Greek eos "dawn" and Latin simius "monkey".^[4]

Dating has proven this genus lived from 45 to 40 million years ago in the middle Eocene.^[4] The genus Eosimias is unique because of the presence of primitive and derived traits. It provides new insight into the phylogenetic relationships between simians and prosimians (especially the phylogenetic position of the haplorhine prosimian tarsiers). It can best be described as a likely tree dweller that relied on a steady diet of insects and nectar.

Most eosimiid species are documented by unique or fragmentary specimens. This, as well as the strong belief that simians originated in Africa has made it difficult for many^[who?] to accept the idea that Asia played a role in early primate evolution. Although some continue to challenge the anthropoid resemblances found in Eosiimidae, extensive anatomical evidence collected over the past decade substantiates its anthropoid status.^{[citation needed]}