Bats
Onychonycteris finneyi
Currently the most primitive bat known — a link between modern bats and their non-flying ancestors.
Bats
Icaronycteris index
A Fossil Lake bat more closely related to modern bats than O. finneyi, with early echolocation.
Bats
Icaronycteris gunnelli
A recently described Fossil Lake bat — more research is still needed on echolocation and its place in bat evolution.
Odd-Toed Ungulates
Protorohippus venticolus
Known from only two FBM specimens — including the most complete dawn-horse skeleton ever found.
Odd-Toed Ungulates
Lambdotherium popoagicum
A brontothere — an odd-toed ungulate from a family that went extinct at the end of the Eocene.
Lemur-Like Mammals
Apatemys chardini
Known from a single FBM specimen — currently the most complete skeleton of this species in the world.
Tube-Sheep
Hyopsodus wortmani
A single FBM skeleton — possibly the most complete hyopsodontid ever discovered.
Otter-Like Carnivores
Palaeosinopa didelphoides
An otter-like swimmer known from three nearshore skeletons — one with fish in the stomach.