Taeniodonta ("banded teeth") is an extinct early group of cimolestid mammals 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 interv ...

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. Variation te ...

quickly into highly specialized digging

animal Animals are multicellular, eukaryotic organisms in the Kingdom (biology), biological kingdom Animalia. With few exceptions, animals Heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, are Motilit ...

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, te ...

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 tars ...

s for digging and rooting. Some genera, like ''

Stylinodon ''Stylinodon'' is an extinct genus of taeniodont mammal, and is the best known, and last genus of taeniodonts, lived some 45 million years ago during middle Eocene in North America. The skull suggests it had a blunt face, and a very short snout ...

'', 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 els ...

to North America. 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 t ...

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'' ::* '' Onychodectes'' ::* Family Conoryctidae :::* '' Conoryctella'' :::* '' 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 ...

:::* '' Chungchienia'' :::* '' Wortmania'' :::* '' Psittacotherium'' :::* '' Ectoganus'' :::* ''

Notes

References

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