''Saghacetus'' is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

basilosaurid Basilosauridae is a family of extinct cetaceans. They lived during the middle to the early late Eocene and are known from all continents, including Antarctica. They were probably the first fully aquatic cetaceans.Buono M, Fordyce R.E., Marx F.G. ...

early whale, fossils of which have been found in the

Upper Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', "da ...

(middle

Priabonian The Priabonian is, in the ICS's geologic timescale, the latest age or the upper stage of the Eocene Epoch or Series. It spans the time between . The Priabonian is preceded by the Bartonian and is followed by the Rupelian, the lowest stage of t ...

, )

Qasr el Sagha Formation The Qasr el Sagha Formation is a geological formation located in Egypt. The formation is part of the Wadi El Hitan World Heritage Site. The Qasr el Sagha Formation overlies the Birket Qarun Formation and is overlain by the Gebel Qatrani Formation ...

Egypt Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Mediter ...

(, paleocoordinates ). Zeuglodon osiris dentary (Dames1894)

In 1879, German botanist

Georg August Schweinfurth Georg August Schweinfurth (29 December 1836 – 19 September 1925) was a Baltic German botanist and ethnologist who explored East Central Africa. Life and explorations He was born at Riga, Latvia, then part of the Russian Empire. He was edu ...

spent many years exploring Africa and eventually discovered the first archaeocete whale in Egypt. He visited Qasr el Sagha in 1884 and 1886 and missed the now famous " Zeuglodon Valley" with a few kilometres. German palaeontologist Wilhelm Barnim Dames described the material, including a well-preserved dentary which is the type specimen of ''Zeuglodon osiris''. The generic name ''Saghacetus'' was established by to group the ancient species ''Dorudon osiris'', ''D. zitteli'', ''D. sensitivius'' and ''D. elliotsmithii'' on a single species, ''Saghacetus osiris''. This species is distinguished from other members of the subfamily

Dorudontinae Dorudontinae are a group of extinct cetaceans that are related to '' Basilosaurus''.. Retrieved July 2013. Classification * Subfamily Dorudontinae ** Genus '' Ancalecetus'' *** ''Ancalecetus simonsi'' ** Genus '' Chrysocetus'' *** ''Chrysocetu ...

by its smaller size and the slightly elongated proximal lumbar and caudal vertebrae. ''Saghacetus'' was a small whale, reaching in length and in body mass. It was smaller than its contemporary ''

Stromerius ''Stromerius'' is an extinct genus of basilosaurid early whale known from the Late Eocene (Priabonian, ) of Fayum, Egypt (, paleocoordinates ). ''Stromerius'' is known from several well-preserved vertebrae. Distinguishing features for the g ...

'', both of which are smaller than the older ''

Dorudon ''Dorudon'' ("spear-tooth") is a genus of extinct basilosaurid ancient whales that lived alongside ''Basilosaurus'' 40.4 to 33.9 million years ago in the Eocene. It was a small whale, with ''D. atrox'' measuring long and weighing . ''Dorudon'' ...

''.

Notes

References

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* * * * Basilosauridae Prehistoric cetacean genera Fossil taxa described in 1992 Eocene mammals of Africa {{paleo-whale-stub