• People's Republic of China
  • Myanmar (?)
  • Eosimias sinensis Beard et al. 1994 ( type)
  • Eosimias centennicus Beard et al. 1996
  • Eosimias dawsonae Beard and Wang 2004
  • Eosimias paukkaungensis (?) Takai et al. 2005

Eosimias ( "Monkey of the Dawn " ) is an extinct genus of mammals and one of the most authentic representative of the Apes ( Anthropoidea ). This genus is so far only by various finds of pines and a few leg bones known that originate from the Middle Eocene of China and three different types are attributed. A possible fourth type is from Myanmar, the assignment of this kind to Eosimias is, however, only temporary.


It was a small representative of the Apes. The lower jaw measuring a length of about 2.6 centimeters; body weight is estimated to be 90 to 180 grams.

As with other representatives of the monkeys the cutting teeth ( incisors ) were relatively small and vertically aligned. The canines were large, the molar teeth ( molars ) were tricuspid and wide. The mandible was relatively low. From advanced monkeys Eosimias however, differs in a number of primitive features: For example, the molars were similar to those of tarsiers, while the incisors are spatulate not like other monkeys, but represent an intermediate form between spatulate and tapering.

Systematics and species

Eosimias is the eponymous representative of the extinct family Eosimiidae. Other members of this family are Bahinia, Phenacopithecus and Philesomias. While the Eosimiidae of the most recent studies as the most primitive group of the Apes ( Anthropoidea ) are considered remarkably critical voices that only very fragmentary fossils would not be sufficient to evaluate the relationships of the group certainly can; for example, well-preserved skull discoveries are needed to confirm the status within a monkey can.

So far the genus Eosimias have been attributed to four types - in addition to the type species Eosimias sinensis (. Beard et al 1994) are the Eosimias centennicus ( Beard et al 1996. ) Eosimias dawsonae ( Beard and Wang 2004) and Eosimias paukkaungensis ( Takai et al. 2005). Christopher Beard and Jingwen Wang (2004), however, noted that the assignment of these species to Eosimias due to the very incomplete fossil record with some uncertainty is affected - so it is possible that future studies will attribute some of the types of other genres. Seems particularly problematic type Eosimias paukkaungensis - this is known only by a pine discovered in Myanmar, but still retains obtained from the dentition only the third molar - the assignment to the genus Eosimias is therefore only provisional.