Metamynodon
Metamynodon is an extinct genus of amynodont that lived in North America from the Middle Eocene to the Middle Oligocene. Metamynodon was a large, robust, and semiaquatic animal that displayed a suite of adaptations towards an amphibious lifestyle. Many of these features showcase convergent evolution with the modern hippopotamus, though Metamynodon is most closely related to rhinoceroses.

Osborn. · Public Domain · via Wikipedia/Commons. May be a photograph of a specimen, or an artist’s reconstruction — an interpretation of a skeleton, since colour and soft tissue are almost never preserved.
On record
Recorded, not inferred- Sits inside
- MetamynodontiniPBDB
- Diet
- browserPBDB
- Life habit
- amphibiousPBDB
- Motility
- actively mobilePBDB, for Osteichthyes
- Environment
- terrestrialPBDB, for Eutheria
Time the record covers
At least 5.8 million years on record.
The record covers at least 39.7 Mya to 33.9 Mya. No occurrence read is dated outside 48.07 Mya to 31.8 Mya.
23 occurrences of Metamynodon on record, most of them in the Eocene. Bar height is expected occurrences, not a count: each fossil is spread across the span it is dated to, so a tall narrow bar means tight dating and a low wide one means loose.
When
23 occurrencesThese are dates about fossils, not the animal: the record can only begin after it arose and end before it died out, so either end may reach further. Shares are expected occurrences: a fossil dated to a span is counted partly in each period it straddles. More on what this infers.
Found in
10 formations
- Pondaung Formation7
- Brule Formation3
- Colmena Tuff Formation2
- Devil's Graveyard Formation2
- Byram Formation2
- Chambers Tuff Formation1
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The named rock units Metamynodon has been recovered from, largest first. Drawn where the rock is now, not where it formed. 2 occurrences have no formation on record, which is common for older literature.
Metamynodon and its relatives
EoceneWhere Metamynodon and its relatives were recorded in the Eocene.
Found in the same rock
142 taxa- Anthracotherium pangan4 sites
- Brontotheriidae4 sites
- Subhyracodon occidentalis3 sites
- Agriochoerus antiquus2 sites
- Allaeochelys magnifica2 sites
- Anthracokeryx birmanicus2 sites
- Anthracokeryx tenuis2 sites
- Anthracotherium crassum2 sites
- Archaeotherium mortoni2 sites
- Bothriodon2 sites
- Brachyhyops wyomingensis2 sites
- Colodon stovalli2 sites
- Duchesneodus uintensis2 sites
- Equidae2 sites
- Hendryomeryx defordi2 sites
- Hoplophoneus primaevus2 sites
- Hyaenodon crucians2 sites
- Hyaenodon montanus2 sites
- Hyracodon2 sites
- Hyracodon medius2 sites
- Indolophus guptai2 sites
- Indomeryx cotteri2 sites
- Ischyromys typus2 sites
- Leptomeryx evansi2 sites
The Paleobiology Database records 22 sites for Metamynodon, and this reads all of them. The number is how many of those sites it was catalogued from too. The 24 sharing the most are listed.
This is not a list of everything alive at the time. It is only what has come out of the same ground as this animal and been written down.
Entered from
17 references- New basal selenodont artiodactyls from the Pondaung Formation (late middle Eocene, Myanmar) and the phylogenetic relationships of early ruminants3
- Early Tertiary Vertebrate Faunas Trans-Pecos Texas: Amynodontidae3
- The Perissodactyla of the Eocene of Burma2
- Fossil mammals of the Lower Miocene White River beds. Collection of 18922
- Synonymies and reidentifications of North American fossil mammals1
- Vertebrate fossil record, age, and paleoenvironmental setting of the Brule Formation (Oligocene) in North Dakota1
- Preliminary report of a Metamynodon skull from the Byram Formation (Lower Oligocene) in Mississippi1
- Stratigraphic Occurrence and Correlation of Early Tertiary Vertebrate Faunas, Trans-Pecos Texas: Agua Fria-Green Valley Areas1
- Preliminary report of a Metamynodon skull from the Byram Formation (lower Oligocene) in Mississippi1
- Early Tertiary Vertebrate Faunas, Trans-Pecos Texas: Ceratomorpha less Amynodontidae1
- Geology and uranium deposits, Shirley Basin area, Wyoming1
- Tertiary geology of the Beaver Rim area, Fremont and Natrona Counties, Wyoming1
Each of the 23 occurrences read was entered from one of these publications, ordered by how many each accounts for. This is not a search for papers mentioning the name. 5 further references are not listed. Entries link to doi.org where the Paleobiology Database holds an identifier, and to its own record where it does not. Relayed as the Paleobiology Database holds them, not checked against what they resolve to.
Media and terms
Media content2
Picture of Metamynodon
- Source
- Wikipedia/Commons
- Credit
- Osborn.
- Licence
- Public Domain
- Commercial use
- the licence allows it
Smithsonian Open Access was not reached for this taxon, so this list is what the others held rather than everything there is.
The description on this site
- Source
- Wikipedia, “Metamynodon”
- Licence
- CC BY-SA 4.0
This is what the site found, which is not the same as what exists.
Keep going
What may have been alongside itMetamynodontini through timeFormations of the EoceneThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. Scott and Osborn 1887