Taeniodonta ("banded teeth") is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

early group of cimolestid

mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur ...

s known from the

Maastrichtian The Maastrichtian () is, in the ICS geologic timescale, the latest age (uppermost stage) of the Late Cretaceous Epoch or Upper Cretaceous Series, the Cretaceous Period or System, and of the Mesozoic Era or Erathem. It spanned the inte ...

to the

Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', ...

. Taeniodonts

evolved Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variati ...

quickly into highly specialized digging

animal Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and go through an ontogenetic stage ...

s, and varied greatly in size, from rat-sized to species as large as a bear. Later species developed prominent front

teeth A tooth ( : teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, ...

and huge

claw A claw is a curved, pointed appendage found at the end of a toe or finger in most amniotes (mammals, reptiles, birds). Some invertebrates such as beetles and spiders have somewhat similar fine, hooked structures at the end of the leg or tarsus ...

s for digging and rooting. Some genera, like '' Stylinodon'', had ever-growing teeth. Two families belong to this group, Stylinodontidae and Conoryctidae. They were

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and th ...

. The scarcity of taeniodont

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

s can be explained by the fact that these animals probably lived in dry or arid climates unconductive to fossilization. Taeniodonts are unambiguously

Eutheria Eutheria (; from Greek , 'good, right' and , 'beast'; ) is the clade consisting of all therian mammals that are more closely related to placentals than to marsupials. Eutherians are distinguished from noneutherians by various phenotypic tra ...

ns, and part of Cimolesta; '' Cimolestes'' is the immediate outgroup to Taeniodonta.

Taxonomy and phylogeny

From Thomas E. Williamson and Stephen L. Brusatte (2013): * Order Cimolesta :* Suborder Taeniodonta ::*'' Alveugena'' ::*''

Schowalteria ''Schowalteria'' is a genus of extinct mammal from the Cretaceous of Canada. It is the earliest known representative of Taeniodonta, a specialised lineage of non-placental eutherian mammals otherwise found in Paleocene and Eocene deposits. It is ...

'' ::* '' Onychodectes'' ::* Family Conoryctidae :::* ''

Conoryctella ''Conoryctella'' was a genus of taeniodont cimolestans. References {{Reflist Cimolestans Prehistoric mammal genera ...

'' :::* '' Huerfanodon'' :::* '' Conoryctes'' ::* Family

Stylinodontidae Taeniodonta ("banded teeth") is an extinct early group of cimolestid mammals known from the Maastrichtian to the Eocene. Taeniodonts evolved quickly into highly specialized digging animals, and varied greatly in size, from rat-sized to species a ...

:::* '' Chungchienia'' :::* '' Wortmania'' :::* ''

Psittacotherium ''Psittacotherium'' (meaning "parrot beast") is an extinct genus of taeniodont from the Paleocene of North America. With a weight of about and a length over , it had similar size of a large dog. References *''Mammoths, Sabertooths, and Hominid ...

'' :::* ''

Ectoganus ''Ectoganus'' is a fossil genus of mammals belonging to the family Stylinodontidae Taeniodonta ("banded teeth") is an extinct early group of cimolestid mammals known from the Maastrichtian to the Eocene. Taeniodonts evolved quickly into highl ...

'' :::* '' Stylinodon''

Notes

References

* * * Cimolestans Paleocene mammals Eocene mammals Priabonian extinctions Prehistoric mammals of North America Clawed herbivores Maastrichtian first appearances {{paleo-mammal-stub