Saturday 22 November 2014

A Protocetid Whale from the early Middle Eocene of Togo, West Africa.

The Earliest Whales appeared in what is now Pakistan and India at the eastern margin of the Tethys Sea then spreading along the southern margin of the Tethys (North Africa) and eventually reaching the Atlantic, then along the west coast of Africa, with specimens known from the later Eocene of Morocco, Senegal and Nigeria.
In a paper published in the Journal of Paleontology in January 2014, Philip Gingerich of the Department of Earth and Environmental Sciences and Museum of Paleontology at the University of Michigan and Henri Cappetta of the Institut des Sciences de l’Evolution at the Université de Montpellier II, describe a new species of Protocetid (the earliest group of Whales known from outside Pakistan and India) from the early Middle Eocene Kpogamé-Hahotoé Phosphate Beds to the northeast of Lomé.

The new species is named Togocetus traversei, where ‘Togocetus’ means ‘Togo-Whale’ and ‘traversei’ the late Michel Traverse of Bourg de Lignerolles in France, who was an operations manager at the Kpogamé-Hahotoé Phosphate Works and collected many vertebrate specimens.

Togocetustraversei is described from a partial left dentary (jawbone), a series of teeth, a series of vertebrae and a number of fragmentary limb bones and ribs. It is thought that most of these bones come from a single specimen, however they were disarticulated and scattered, probably due to predation or scavenging shortly after death, and many bones were also broken by the actions of heavy machinery at the site.

Dentary remains of middle Lutetian Togocetus traversei, from Kpogamé-Hahotoé. (1, 2) Partial left dentary with roots oralveoli for a single-rooted P1 and double-rooted P2–4, in occlusal and left lateral view; (3) partial right dentary with roots for M2–3; (4, 5) partial left dentary with M3; (6), right dentary with the alveolus for C1; and partial crowns of P1–M2. Note the narrow, deep dentaries; endof the mandibularsymphysis near the anterior root of P3; diastemata separating C1, P1, P2, P3 and P4; and unusually small mandibular canal for a protocetid. Abbreviation: mc = mandibular canal. Gingerich & Cappetta (2014).

Gingerich and Cappetta also report the remains of two other Protocetids from the site, as well as a Protosirenid (early Sirenian) a Dugong and some unidentified Mammal bones.

See also…

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