Paracathartes
Encyclopedia
Paracathartes is a genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of extinct bird from the Wasachtian horizon of lower Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...

 Wyoming, USA. One species, Paracathartes howardae has been described.

It is a paleognathous
Paleognathae
The Palaeognathae or paleognaths are one of the two living superorders of birds. The other living superorder is Neognathae. Together these two clades form the subclass Neornithes....

 bird, turkey-like in stature and size, that probably resembled a tinamou
Tinamou
The tinamous are a family comprising 47 species of birds found in Central and South America. One of the most ancient living groups of bird, they are related to the ratites. Generally ground dwelling, they are found in a range of habitats....

 quite closely.

Parachathartes was described by Harrison as the earliest known cathartid vulture. Rich criticized this assignment. Houde (1988) included it as a member of the order Lithornithiformes
Lithornithiformes
Lithornithiformes is an extinct order of early paleognath birds. Lithornithiform birds are known from fossils dating to the Upper Paleocene through the Middle Eocene of North America and Europe. All are extinct today....

 and family Lithornithidae
Lithornithidae
Lithornithidae are a family of palaeognathous birds from the early Tertiary of the northern hemisphere.-Species:The family was erected by Peter Houde in 1988. It includes the genera Lithornis, Paracathartes, and Pseudocrypturus...

.

The holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...

 specimen is in the collection of the Royal Ontario Museum
Royal Ontario Museum
The Royal Ontario Museum is a museum of world culture and natural history in Toronto, Ontario, Canada. With its main entrance facing Bloor Street in Downtown Toronto, the museum is situated north of Queen's Park and east of Philosopher's Walk in the University of Toronto...

. It has catalog number ROM 22658. It is the distal end of a left tibiotarsus
Tibiotarsus
The tibiotarsus is the large bone between the femur and the tarsometatarsus in the leg of a bird. It is the fusion of the proximal part of the tarsus with the tibia.A similar structure also occurred in the Mesozoic Heterodontosauridae...

. It was collected by G. E. Lindblad and G. Sternberg on 4 August 1949. It was found at the northernmost branch of Elk Creek, near Basin, Wyoming
Basin, Wyoming
Basin is a town in, and the county seat of, Big Horn County, Wyoming, United States. The population was 1,239 at the 2000 census. The community is located near the center of the Bighorn Basin with the Big Horn River east of the town...

. The horizon is Greybullian, middle Wasatchian
Wasatchian
The Wasatchian North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology , typically set from 55,400,000 to 50,300,000 years BP lasting . It is usually considered to be within the Eocene, more specifically the...

 (early Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...

), Willwood Formation, Bighorn Basin.

Further specimens of Paracathartes were collected , including almost the whole skeleton (USNM 361402-361446, 391984, 404747-404806) from at least five individuals preserved together. These bones were associated with three whole eggs (USNM 336564) and an avian neurocranium (USNM 361415) which may belong to paracathartes or to a possible phorusrhacid.
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