Herpetotheriidae is an extinct

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

metatheria Metatheria is a mammalian clade that includes all mammals more closely related to marsupials than to placentals. First proposed by Thomas Henry Huxley in 1880, it is a more inclusive group than the marsupials; it contains all marsupials as wel ...

ns, closely related to

marsupial Marsupials are any members of the mammalian infraclass Marsupialia. All extant marsupials are endemic to Australasia, Wallacea and the Americas. A distinctive characteristic common to most of these species is that the young are carried in a ...

s. Species of this family are generally reconstructed as

terrestrial Terrestrial refers to things related to land or the planet Earth. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on or near the ground, as opposed to ...

, and are considered morphologically similar to modern

opossums Opossums () are members of the marsupial order Didelphimorphia () endemic to the Americas. The largest order of marsupials in the Western Hemisphere, it comprises 93 species in 18 genera. Opossums originated in South America and entered North A ...

. Fossils of herpetotheriids come from North America, Asia, Europe, Africa, and perhaps South America. The oldest representative is '' Maastrichtidelphys'' from the latest

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...

(

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 interval ...

) of the Netherlands and the youngest member is '' Amphiperatherium'' from the Middle Miocene of Europe. The group has been suggested to be paraphyletic, with an analysis of petrosal anatomy finding that North American ''

Herpetotherium ''Herpetotherium'' is an extinct genus of metatherian mammal, belonging to the possibly paraphyletic family Herpetotheriidae. Native to North America from the Eocene to Early Miocene, fossils have been found in California, Oregon, Texas, Florida ...

'' was more closely related to marsupials than the European '' Peratherium'' and ''Amphiperatherium.'' The family includes the following genera: *'' Amphiperatherium'' ( Early Eocene to Middle Miocene, Europe; synonyms: ''Oxygomphius'', ''Microtarsioides'', ''Ceciliolemur'') *'' Asiadidelphis'' (

Late 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'', "d ...

Early Oligocene The Rupelian is, in the geologic timescale, the older of two ages or the lower of two stages of the Oligocene Epoch/ Series. It spans the time between . It is preceded by the Priabonian Stage (part of the Eocene) and is followed by the Chattian ...

, Kazakhstan and Pakistan) *'' Copedelphys'' (

to Early Oligocene, North America) *'' Entomacodon'' (

Middle 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'', "da ...

, North America; synonym: ''Centracodon'') *'' Golerdelphys'' (

Late Paleocene The Thanetian is, in the ICS Geologic timescale, the latest age or uppermost stratigraphic stage of the Paleocene Epoch or Series. It spans the time between . The Thanetian is preceded by the Selandian Age and followed by the Ypresian Age (p ...

, North America) *'' Galatiadelphys'' (Middle Eocene, Turkey) *''

'' (Early Eocene to Middle Miocene, North America) *'' Maastrichtidelphys'' (

, Europe) *'' Nortedelphys'' ( Lancian, North America) *'' Peratherium'' (Early Eocene to

Early Miocene The Early Miocene (also known as Lower Miocene) is a sub-epoch of the Miocene epoch (geology), Epoch made up of two faunal stage, stages: the Aquitanian age, Aquitanian and Burdigalian stages. The sub-epoch lasted from 23.03 ± 0.05 annum, Ma to ...

, Europe;

, Egypt, Oman; synonyms: ''Alacodon'', ''Qatranitherium'') *'' Swaindelphys'' (

Early Paleocene The Danian is the oldest age (geology), age or lowest stage (stratigraphy), stage of the Paleocene epoch (geology), Epoch or series (stratigraphy), Series, of the Paleogene period (geology), Period or system (stratigraphy), System, and of the Ce ...

, North America) *'' Morotodon'' (Early to Middle Miocene, Uganda) The following genera have been placed in the family, but their placement is disputed or obsolete: *'' Garatherium'' (Early Eocene of Algeria) – possibly an adapisoriculid eutherian *'' Indodelphis'' (Early Eocene of India) – originally referred to Peradectidae *''

Jaegeria ''Jaegeria'' is a genus of flowering plants in the family Asteraceae found from Mexico to South America. The name commemorates Georg Friedrich von Jaeger. ; Species * ''Jaegeria axillaris'' S.F.Blake - Colombia * ''Jaegeria bellidiflora'' (Moc. ...

'' (Early Eocene of India) – a bat *'' Rumiodon'' ( Paleogene of Peru) – placement uncertain

References

Literature cited

* * * * * * * * * Prehistoric metatherians Late Cretaceous first appearances Miocene extinctions Prehistoric mammal families {{cretaceous-mammal-stub