| Samburupithecus Temporal range: 9.5 Million years ago | |
|---|---|
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| Samburupithecus kiptalami fossils,Muséum national d'histoire naturelle, Paris | |
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Primates |
| Superfamily: | Hominoidea |
| Family: | incertae sedis |
| Genus: | †Samburupithecus Ishida & Pickford 1997 |
| Species: | †S. kiptalami |
| Binomial name | |
| †Samburupithecus kiptalami | |
Samburupithecus is an extinctprimate that lived inKenya during the middle to lateMiocene. The one species in this genus,Samburupithecus kiptalami, is known only from amaxilla fragment dated to 9.5 million years ago discovered in 1982[1] and formally described byIshida & Pickford 1997.[2] The type specimen KNM-SH 8531 was discovered by the Joint Japan-Kenya Expedition at the SH22 fossil site in theSamburu District,[1] a locality where several other researchers found no ape fossils.[3]
Samburupithecus lived during the so-called "African ape gap"14 to 7 Ma, a period from which very few hominoid fossils have been found inAfrica until relatively recently.[3] This apparent gap, however, is now populated by a diversity of apes such asNakalipithecus,Chororapithecus abyssinicus,[3]Otavipithecus,[4] andNacholapithecus.[5]
Samburupithecus was approximately 60 kilograms (130 lb)[6] and was most likely afrugivorousterrestrialquadruped. Paleoenvironmental reconstructions indicate thatSamburupithecus most likely lived in a wooded habitat surrounded bysavannah.[7]
Defining cranial traits of this genus include low, broadzygomatics, straightalveolar process and largemaxillary sinus. Defining dental traits include three-rootedpremolars, thickenamel andbunodont cusps.[8]
The teeth in theSamburupithecus type maxilla are comparable in size to those of the type mandible ofNakalipithecus, roughly the size of a modern female gorilla. The upper premolars of both are elongatedmesiodistally (along the row of teeth), but those ofSamburupithecus have more inflated cusps that are positioned more centrally, so that occlusal foveae and basins (depressions at top of teeth) are very restricted. This suggests thatSamburupithecus was strongly specialized compared to other Miocene and extant apes. Another distinguishing feature between the two is the higher relief of thedentine/enamel junction inSamburupithecus.[9]
These elongated teeth are unlike many other Miocene hominoids, linkingSamburupithecus the taxon togorillas,chimpanzees andhominins, but its relationships within thisclade is at present unclear.[10] Because of this mixture of primitive and derived traits in the KNM-SH 8531 specimen, it has been proposed thatSamburupithecus lived before the gorilla-chimpanzee-hominin split and, therefore, that it is acommon ancestor to these primates alongsideOuranopithecus.[11]
