Steropodontidae is an extinct

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of early monotreme mammals known from the

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Taxonomy

''Steropodon'' was initially placed in the crown group monotreme family Ornithorhynchidae but was subsequently made the type genus of Steropodontidae, its own

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

family. The monotreme '' Teinolophos'' was suggested to also belong in this family, before also being placed in a distinct family. '' Parvopalus'', known from the same locality as ''Steropodon'', may be a steropodontid.

Description

Steropodontids are small monotremes; ''Steropodon'' has an estimated body mass of , and ''Parvopalus'' represents the smallest mammal found in its faunal assemblage. Members of this clade are characterized by having narrow and tall dentaries compared to other monotremes, and a prominent ascending ramus of the dentary.

References

Prehistoric monotremes Prehistoric mammal families Taxa named by Mike Archer (paleontologist) Taxa named by Tim Flannery {{paleo-mammal-stub