U is for Uintatherium – #AtoZChallenge – 2017 – Uintan Mammals

U is for Uintatherium

Uintatherium was a massive hoofed mammal that lived during the Eocene epoch. Superficially, they were rather rhinoceros-like, though they were not related.

A reconstruction of Uintatherium.
Credit: Dmitry Bogdanov CC 3.0 By SA

Notably, Uintatheres had many horns and protuberances on their skulls, in addition to robust tusks.

Cast of Uintatherium anceps (Leidy, 1872) – syn. Dinoceras mirabile (Marsh 1872) skull, neck vertebrae.
Credit: Jebulon [Public Domain]

O is if Ourayia – #AtoZChallenge – 2017 – Uintan Mammals

O is for Ourayia

Ourayia is a fossil primate, which, like Notoparamys, is related to tarsiers. Like many fossil mammals, it is best known for its teeth.

VPPU.011236: Ourayia uintensis: HYPODIGM. Utah. Uintah County. Kennedy’s Hole, Uinta Basin. Princeton 1895 Hatcher Expedition. Coll: Hatcher, J. B. 25 Mar 1895. Tertiary. Late Eocene. Uintan. Uinta Fm. Middle Uinta B.
Courtesy of the Peabody Museum of Natural History,
Division of Vertebrate Paleontology, Yale University; peabody.yale.edu

Isostylomys: A Rodent of Unusual Size – #365papers – 2017 – 107

#365papers for April 17, 2017

Rinderknecht, Bostelmann, annd Ubilla, 2017, Making a giant rodent: cranial anatomy and ontogenetic development in the genus Isostylomys (Mammalia, Hystricognathi, Dinomyidae): Journal of Systematic Palaeontology, DOI: 10.1080/14772019.2017.1285360.

What’s it about?

Isostylomys is (was) a giant rodent from the Miocene of Uruguay. By giant, I mean larger than the largest rodent today. I mean huge.

The authors here discuss the status of the genus and its relationships with other rodents. Importantly, they show how it is very possible that some species of South American large rodents might be juvenile forms of giant rodents like Isostylomys. Continue reading

The Shortest-Necked of the Long-Necked Elasmosaurs – #365papers – 2017 – 108

#365papers for April 18, 2017

Serratos, Druckenmiller, and Benson, 2017, A new elasmosaurid (Sauropterygia, Plesiosauria) from the Bearpaw Shale (Late Cretaceous, Maastrichtian) of Montana demonstrates multiple evolutionary reduction of neck length within Elasmosauridae: Journal of Vertebrate Paleontology e1278608.

What’s it about?

Elasmosaurids were marine reptiles that are considered a sub-group of the plesiosaurs. Distinctive features of elasmosaurids are their very long necks and small heads. Here, a new species of elasmosaurid is described that had a relatively short neck and was also fairly small. Continue reading

What Really Is Ichthyosaurus? – #365papers – 2017 – 106

#365papers for April 16, 2017

Massare and Lomax, 2017, A taxonomic reassessment of Ichthyosaurus communis and I. intermedius and a revised diagnosis for the genus: Journal of Systematic Paleontology. DOI: 10.1080/14772019.2017.1291116.

What’s it about?

Ichthyosaurus is (or was) a type of marine reptile that looked sort of dolphin-like.

Ichthyosaurus communis from the Natural History Museum in London. Credit Gehdoghedo CC 3.0 By SA

Ichthyosaurus communis life reconstruction.
Credit: Nobu Tamura CC BY 3.0

Here, the authors work to distinguish between three common species of Ichthyosaurus, I. communis, I. intermedius, and I. breviceps. The authors also present a better definition for the genus Ichthyosaurus. Continue reading