List of the prehistoric life of Montana

This list of the prehistoric life of Montana contains the various prehistoric life-forms whose fossilized remains have been reported from within the US state of Montana.

The Paleobiology Database records no known occurrences of Precambrian fossils in Montana.

Life restoration of the Carboniferous lobe-finned fish Allenypterus
Restoration of the Carboniferous Chimaera relative Belantsea
Fossilized skeleton of the Carboniferous coelacanth Caridosuctor
Fossilized shell of the Late Devonian-Permian brachiopod Composita
Life restoration of the Carboniferous Chimaera relative Delphyodontos
†Echinochimaera meltoni Lund 1977 from the Mississippian of Bear Gulch
Restoration (bottom) of the Carboniferous "antlered" Chimaera relative Harpagofututor
Fossil of the Cambrian-Silurian trilobite Megistaspis
Fossilized theca of the Carboniferous blastoid echinoderm ("sea bud") Pentremites
Fossilized shell of the Late Ordovician-Late Triassic brachiopod Spirifer
Life restorations of a male (foreground) and female (background) of the Late Devonian-Carboniferous Chimaera relative Stethacanthus
Life restoration of the Late Cretaceous horned dinosaur Achelousaurus
Life restoration of the Late Jurassic theropod dinosaur Allosaurus
Image of restored specimen of a squat quadruped with knobby back
Life restoration of the Late Cretaceous armored dinosaur Ankylosaurus
Life restoration of the Late Cretaceous toothed bird Avisaurus with prey
Mounted fossilized skeleton of the Cretaceous turtle Basilemys
Fossilized natural mummy of the Late Cretaceous duck-billed dinosaur Brachylophosaurus
Life restoration of the Late Cretaceous-Eocene choristoderan reptile Champsosaurus
Life restoration of the face of the Late Cretaceous multituberculate mammal Cimolomys
Mounted fossilized skeleton of the Late Cretaceous duck-billed dinosaur Corythosaurus
Life restoration of the Early Cretaceous dromaeosaur ("raptor") Deinonychus
Life restoration of the Late Jurassic long-necked dinosaur Diplodocus
Life restoration of the Late Cretaceous duck-billed dinosaur Edmontosaurus annectens
Restoration of the Late Cretaceous armored dinosaur Euoplocephalus
Mounted fossilized skeleton of the Middle Jurassic-Late Cretaceous mammal Gobiconodon
Life restoration of the Late Cretaceous toothed bird Hesperornis
Fossilized shell of the Early Jurassic-Late Cretaceous marine bivalve Inoceramus with a human indicating its size
Life restoration of the Late Cretaceous horned dinosaur Judiceratops
Life restoration of the Late Cretaceous primitive horned dinosaur Leptoceratops
Mounted fossilized skeletons of the Late Cretaceous pterosaur Montanazhdarcho
A living Nelumbo lotus
A living Odontaspis sand shark
Life restoration of the Late Cretaceous herbivorous dinosaur Oryctodromeus in a burrow
Illustration of a fossilized skull of the Late Cretaceous armored dinosaur Panoplosaurus
Fossilized shell of the Late Cretaceous ammonoid cephalopod Parapuzosia with a human indicating its size
Mounted fossilized skeleton of the Late Cretaceous duck-billed dinosaur Prosaurolophus
Life restoration of a flock of the Late Cretaceous pterosaur Quetzalcoatlus feeding on the ground
Life restoration of the Early Cretaceous armored dinosaurs Sauropelta
Base of the trunk of a living Sequoia tree with a human to scale
Restoration of the Late Cretaceous horned dinosaur Spiclypeus
Life restoration of the Early Cretaceous Iguanodon relative Tenontosaurus
Mounted fossilized skeleton of the Late Cretaceous horned dinosaur Triceratops
Fossilized skeleton of the Late Cretaceous tyrannosaur Tyrannosaurus
Fossil of the Early Triassic-Eocene cycad-like frond Zamites
Mounted fossilized skeleton of the Miocene horse Acritohippus
Life restoration of the Miocene elephant relative Amebelodon . Margret Flinsch (1932).
Living Azolla water ferns
Mounted fossilized skeleton of the Pleistocene Bison latifrons , also known as the giant bison or long-horned bison
Life restoration of the Paleocene primate relative Carpolestes
Life restoration of the Late Cretaceous-Eocene choristoderan reptile Champsosaurus
A living Cinnamomum , or cinnamon tree
Fossilized leaf from a Credneria tree
Life restoration of the Eocene-Miocene false saber-toothed cat Dinictis . Robert Bruce Horsfall (1913).
Fossilized horns, jaws, and limb bones of the Miocene deer relative Dromomeryx
Fossilized fruit of the Eocene Eucommia montana plant
Fossilized skull of the Oligocene lizard Helodermoides
Restoration of Pliocene-Pleistocene Homotherium , or scimitar cat
Life restoration of the Miocene horse Hypohippus . Heinrich Harder (1920).
Restoration of the Oligocene-Miocene oreodont mammal Leptauchenia
A living Lynx rufus , or bobcat
Life restoration of battling males of the Eocene brontothere mammal Megacerops
Restorative portrait of the Oligocene-Miocene oreodont mammal Merycochoerus
Life restoration of the Paleocene-Eocene mammal Miacis
Life restoration of a herd of Neohipparion . Robert Bruce Horsfall (1913).
A living Odocoileus deer
Life restoration of a pair of the Oligocene-Miocene camel Oxydactylus . Robert Bruce Horsfall (1913).
Fossilized skeleton of the Pliocene-Pleistocene ground sloth Paramylodon
Life restoration of the Paleocene-Eocene ungulate Phenacodus . Charles R. Knight (1898).
Illustration of a fossilized skull of the Oligocene false faber-toothed cat Pogonodon
Fossil of the Oligocene ant Protazteca
Restoration of the Paleocene taeniodont mammal Psittacotherium multifragum
Life restoration of the Late Cretaceous-Paleocene primate relative Purgatorius
Fossilized leaf of the Eocene sassafras Sassafras hesperia
Life restoration of the Oligocene-Miocene camel Stenomylus
Life restoration of the Eocene carnivoran relative Tapocyon
Life restoration of the Paleocene pantodonts mammal Titanoides