Parictis Explained

Parictis is an extinct arctoid belonging to the family Subparictidae.

Taxonomy & evolution

It was originally described as a new genus and species Parietis princeous of mustelid by Scott in 1893, for a single specimen, a mandible fragment with two anterior molars.^[1] An alternative name and spelling, ?Parictis princeps, was proposed in 1894;^[2] and in 1904 both the genus and species name were declared to be in error and the name Parictis primaevus was assigned.^[3]

Parictis bathygenus was described in 1947, but it was considered a different genus by 1958, and a synonym of Cynelos caroniavorus by 1976.^{[4] [5]}

Another species was described in 1954 as Campylocynodon personi,^[6] and was reassigned to the genus Parictis in 1967.^[7] And Parictis major was described during a review of the genus in 1972.^[8]

The genus as a whole was placed within various families, including Canidae by Hall in 1931 and Ursidae by Hunt in 1998.^{[9] [10]} It is placed within the family Subparictidae as of 2023.^[11]

Description

It was a very small and graceful arctoid with a skull only 7 cm long. Parictis first appeared in North America in the Late Eocene (around 38 million years ago), but it did not arrive in Eurasia until the Miocene.^[12] Some suggest that Parictis may have emigrated from Asia into North America during the major sea level low about 37 mya, because of the continued evolution of the Amphicynodontinae into the Hemicyoninae in Asia.^[13] Although no Parictis fossils have been found in East Asia, Parictis does appear in Eurasia and Africa, but not until the Miocene.

Notes and References

1. Scott . W. B. . 1893 . On a new musteline from the John Day Miocene . American Naturalist . 27 . 658–659 .
2. Lyddeker . R. . 1894 . II. Mammalia . The Zoological Record . 30 . 29 .
3. Hay . O.P. . 1902 . Bibliography and catalogue of fossil Vertebrata of North America . Bulletin of the United States Geological Survey . 179 . 767 .
4. Olsen, Stanley J.. 1958. Some problematical carnivores from the Florida Miocene. Journal of Paleontology. 32. 3. 595–602. 1300686.
5. Book: Tedford, Richard H. . Frailey, David . 1976. Review of some Carnivora (Mammalia) from the Thomas Farm local fauna (Hemingfordian, Gilchrist County, Florida). American Museum Novitates; no. 2610. New York. American Museum of Natural History. 2.
6. Chaffee. Robert G.. Campylocynodon personi, a New Oligocene Carnivore from the Beaver Divide, Wyoming. Journal of Paleontology. 1954. 28. 1. 43–46. 1300205 .
7. Clark . J. . Beerbower . J. R. . 1967 . Geology, paleoecology, and paleoclimatology of the Chadron Formation . Fieldiana . 5 . 5 . 21–74 .
8. Clark . J. . Guensburg . T. E. . 1972 . Arctoid genetic characters as related to the genus Parictis . Fieldiana: Geology . 26 . 1–71 . 10.5962/bhl.title.3434 . free .
9. Hall, E. Raymond. 1931. Description of a New Mustelid from the Later Tertiary of Oregon, with Assignment of Parictis primaevus to the Canidae. Journal of Mammalogy. 12. 2. 156–158. 10.2307/1373915. 1373915.
10. Book: Hunt, R. M. Jr.. 1998. Ursidae. Janis, Christine M. . Scott, Kathleen M. . Jacobs, Louis L. . Evolution of Tertiary Mammals of North America, volume 1: Terrestrial carnivores, ungulates, and ungulatelike mammals. Cambridge, England. Cambridge University Press. 174–195. 978-0-521-35519-3.
11. Wang. Xiaoming. Emry. Robert J.. Boyd. Clint A.. Person. Jeff J.. White. Stuart C.. Tedford. Richard H.. An exquisitely preserved skeleton of Eoarctos vorax (Nov. Gen. Et sp.) from Fitterer Ranch, North Dakota (Early Oligocene) and systematics and phylogeny of North American early arctoids (Carnivora, Caniformia). Journal of Vertebrate Paleontology. 2022. 42. 1–123. 10.1080/02724634.2022.2145900 . 2022JVPal..42S...1W. 259025727. free.
12. Book: Kemp, T. S.. 2005. The Origin and Evolution of Mammals. limited. Oxford University Press. 260 . 978-0-19-850760-4.
13. Several students (Erdbrink 1953, Kurten 1966, Mitchell and Tedford 1973, Thenius 1979) suggested that the evolutionary line between the canid subfamily Amphicynodontinae and the ursid subfamily Hemicyoninae was through the genera Cephalogale and Ursavus. Book: McLellan, Bruce . Reiner, David C. . amp . 1994. A review of bear evolution. Claar, James J.. Bears: Their Biology and Management: Ninth International Conference on Bear Research and Management. International Association for Bear Research and Management . 85–96 . 978-0-944740-04-0 . etal.