| Didymoconus | |
|---|---|
 | |
| Holotype skull ofD. colgatei | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Family: | †Didymoconidae |
| Subfamily: | †Didymoconinae |
| Genus: | †Didymoconus Matthew & Granger, 1924 |
| Type species | |
| †Didymoconus colgatei Matthew & Granger, 1924 | |
| Other species | |
| Synonyms | |
Didymoconus is an extinct genus of mammal that lived during the earlyOligocene epoch. It was endemic to Asia, and its fossils have been found inMongolia,China andKazakhstan.[1] It is the type genus of theDidymoconidae, a family ofeutherian mammals with uncertain taxonomic affinities.[2]
Fossilized remains ofDidymoconus were first discovered during the Central Asiatic Expeditions of theAmerican Museum of Natural History in the 1920s. In 1924, Matthew & Granger erected the genus withD. colgatei as thetype species, while also erecting the speciesD. berkeyi. Theholotype ofD. colgatei is a skull (AMNH 19124), and two lower jaws (AMNH 19003 & 19004) were established asparatypes, while the type specimen ofD. berkeyi is a set of lower jaws (AMNH 19001). All these specimens were collected from theHsanda Gol Formation of Mongolia.[3]
Gromova (1960) erected the genusTshelkaria withT. rostrata as the type species, the holotype for this species being collected fromKazakhstan. An additional species,T. robusta, was also referred to this genus.[4] Though this genus was initially deemed distinct fromDidymoconus based on certain dental features, these features were later noted to be present in the holotype ofDidymoconus colgatei, and thusTshelkaria is currently recognized as ajunior synonym ofDidymoconus.T. rostrata is now placed inDidymoconus asD. rostrata, whileT. robusta is a junior synonym ofD. colgatei.[2]
In 1997, Lopatin assigned a fourth species to the genus. NamedDidymoconus gromovae, it is named after paleontologist V.I. Gromova. The holotype of this species is a fragment of the leftmandibular ramus collected from theChelkamura Formation ofChalkar-Teniz, Kazakhstan.[5]