The Tsaganomyidae are an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

family of

rodent Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and Mandible, lower jaws. About 40% of all mammal specie ...

s from

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

. It contains three genera. Tsaganomyids are generally considered to be related to the

Hystricognathi The Hystricognathi are an infraorder of rodents, distinguished from other rodents by the bone structure of their skulls. The masseter medialis (a jaw muscle) passes partially through a hole below each eye socket (called the infraorbital foramen) ...

(

porcupine Porcupines are large rodents with coats of sharp Spine (zoology), spines, or quills, that protect them against predation. The term covers two Family (biology), families of animals: the Old World porcupines of the family Hystricidae, and the New ...

s and relatives). Members of Tsaganomyidae were

fossorial A fossorial animal () is one that is adapted to digging and which lives primarily (but not solely) underground. Examples of fossorial vertebrates are Mole (animal), moles, badgers, naked mole-rats, meerkats, armadillos, wombats, and mole salamand ...

(digging) rodents that probably used their

incisor Incisors (from Latin ''incidere'', "to cut") are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight (two on each side, top and bottom). Opossums have 18, wher ...

teeth to dig like some living mole rats.

Characteristics

Tsaganomyids had a protrogomorphous

zygomasseteric system The zygomasseteric system (or zygomasseteric structure) refers to the anatomical arrangement of the masseter muscle and the zygomatic arch (cheek bone) in the skulls of Rodent, rodents. This system plays a crucial role in the diverse chewing mechan ...

, a hystricognathous lower jaw, and multiserial enamel in their incisor teeth.

References

Hystricomorpha Prehistoric rodent families Rupelian first appearances Miocene extinctions {{paleo-rodent-stub