Z is for Zionodon
Zionodon is an adorable little insectivorous mammal related to modern elephant shrews. You may squee now.
Here’s a skeleton of a close fossil relative, Macrocranion tupaiodon:
Credit Ghedoghedo CC 3.0 By-SA
Y is for Yerbua
Yerbua is a genus of hopping rodent. The name “Yerbua” was coined in 1778, but has since been replaced with “Pedetes.” I have this name written down as a Uintan mammal, but Pedetes is a modern taxon from Africa, so I’m not sure what happened. But here you go:
Spring Hare, Pedetes capensis. Credit: Bernard DuPont CC 2.0 By-SA
X is for Xylotitan
Xylotitan is a new species of brotothere, a hoofed mammal related to horses and rhinos. Brototheres were giant mammals, considered the earliest of the ‘megaherbivores.’
Among brototheres, Xylotitan is among the smallest, only about the size of a large tapir.
This new species was named in 2016 by Mihlbachler and Samuels.
W is for Washakius
Washakius is a primate known only from the Eocene of the United States.
Skull element, right lower jaw, T-P2-M1
V is for Viverravus
Viverravus is a carnivorous mammal. Interestingly, I have written up Viverravus in an earlier A to Z Challenge about Paleocene mammals, here. Viverravus as a genus lasted many millions of years.
Here is an early Eocene Viverravus from the Yale-Peabody Museum:
Viverravus sp. YPM VPPU 022652. right ramus with P/4, M/1
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]
T is for Tapocyon
Tapocyon is a genus of miacid carnivores that lived during the Paleocene and Eocene epochs of North America. It was a climbing mammal that likely spent a great amount of time in trees.
Life reconstruction of Tapocyon robustus.
Credit: Nobu Tamura CC 4.0 By SA
S is for Smilodectes
Smilodectes is an extinct primate that lived in North America during the Eocene.
Early Eocene (55-50 mya); Smilodectes gracilis, Smithsonian National Museum of Natural History.
Credit: Ryan Somma CC 2.0 By-SA
R is for Reithroparamys
Reithroparamys is another extinct rodent from North America. Species of this genus ranged from the late Paleocene into the mid-Eocene. Four species are known from this genus.
Q is for Quadratomus
Quadratomus is an Eocene rodent. There are four species within this genus all of which lived in North America.