Probathyopsis

Probathyopsis; Temporal range: Late Paleocene–Early Eocene PreꞒ Ꞓ O S D C P T J K Pg N
	Evolution of the teeth of the Dinocerata, with "Probathyopsis sucessor" (above, now considered a synonym of P. praecursor) and Probathyopsis praecursor (below)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	†Dinocerata
Family:	†Prodinoceratidae
Genus:	†Probathyopsis; Simpson, 1929
Species
	P. harrisorum (Patterson, 1939); P. lysitensis (Kelley and Wood, 1954); P. praecursor (Simpson, 1929); P. sinyuensis (Chow and Tung, 1962);
Synonyms
	P. newbilli; P. sucessor; Prouintatherium;

Probathyopsis, from Ancient Greek πρό (pró), meaning "before", βαθύς (bathús), meaning "thick", and ὄψις (ópsis), meaning "face", is an extinct genus of dinocerate mammal from Paleocene North America.^[1]

Description

Probathyopsis is incredibly basal compared to the later dinocerates in terms of anatomical characteristics. The genus lacks the characteristic skull knobs, unlike derived dinocerates. The flange on the mandible is also less developed as in later members of the clade, like Uintatherium. The lower molars are also longer and narrower than in later members of the group.^[2] The genus was sexually dimorphic, with males being larger and having larger mandibular flanges.^[3]

Classification

The classification history of Probathyopsis is convoluted. It has been suggested at times to be a synonym of Prodinoceras,^[3] though there is debate to this as many authors still recognize the genus as valid.^[4]^[5] Currently the genus is believed to be among the most basal of all dinocerates and is grouped closely with Prodinoceras, in the family Prodinoceratidae.^[1]

References

^ ^a ^b Thewissen, J. G. M.; Gingerich, Philip D. (1987). Systematics and Evolution of Probathyopsis (mammalia, Dinocerata) from the Late Paleocene and Early Eocene of Western North America. Museum of Paleontology; The University of Michigan.
^ Simpson, George Gaylord. "A new Paleocene uintathere and molar evolution in the Amblypoda. American Museum novitates ; no. 387". Biodiversity Heritage Library. Retrieved 2025-10-07.
^ ^a ^b Choch, Robert M.S.; Lucas, Spencer G. (February 15, 1984). "The phylogeny and classification of the Dinocerata (Mammalia, Eutheria)" (PDF). Department of Geology and Geophysics and Peabody Museum of Natural History, Yale University.
^ Secord, Ross; Gingerich, Philip D.; Smith, M. Elliot; Clyde, William C.; Wilf, Peter; Singer, Brad S. (2006-04-01). "Geochronology and Mammalian Biostratigraphy of Middle and Upper Paleocene Continental Strata, Bighorn Basin, Wyoming". American Journal of Science. 306 (4): 211–245. Bibcode:2006AmJS..306..211S. doi:10.2475/ajs.306.4.211.
^ Wilf, Peter; Beard, K. Christopher; Davies-Vollum, K. Sian; Norejko, Jay W. (December 1998). "Portrait of a Late Paleocene (Early Clarkforkian) Terrestrial Ecosystem: Big Multi Quarry and Associated Strata, Washakie Basin, Southwestern Wyoming". PALAIOS. 13 (6): 514. Bibcode:1998Palai..13..514W. doi:10.2307/3515344. JSTOR 3515344.

[:1-1] Thewissen, J. G. M.; Gingerich, Philip D. (1987). Systematics and Evolution of Probathyopsis (mammalia, Dinocerata) from the Late Paleocene and Early Eocene of Western North America. Museum of Paleontology; The University of Michigan.

[2] Simpson, George Gaylord. "A new Paleocene uintathere and molar evolution in the Amblypoda. American Museum novitates ; no. 387". Biodiversity Heritage Library. Retrieved 2025-10-07.

[:0-3] Choch, Robert M.S.; Lucas, Spencer G. (February 15, 1984). "The phylogeny and classification of the Dinocerata (Mammalia, Eutheria)" (PDF). Department of Geology and Geophysics and Peabody Museum of Natural History, Yale University.

[4] Secord, Ross; Gingerich, Philip D.; Smith, M. Elliot; Clyde, William C.; Wilf, Peter; Singer, Brad S. (2006-04-01). "Geochronology and Mammalian Biostratigraphy of Middle and Upper Paleocene Continental Strata, Bighorn Basin, Wyoming". American Journal of Science. 306 (4): 211–245. Bibcode:2006AmJS..306..211S. doi:10.2475/ajs.306.4.211.

[5] Wilf, Peter; Beard, K. Christopher; Davies-Vollum, K. Sian; Norejko, Jay W. (December 1998). "Portrait of a Late Paleocene (Early Clarkforkian) Terrestrial Ecosystem: Big Multi Quarry and Associated Strata, Washakie Basin, Southwestern Wyoming". PALAIOS. 13 (6): 514. Bibcode:1998Palai..13..514W. doi:10.2307/3515344. JSTOR 3515344.

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