Monotherium
Monotherium is an extinct genus of phocid belonging to the subfamily Monachinae. It is known from fossils found in the middle to late Miocene of Belgium.

via iDigBio · via iDigBio. 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
- MonachinaePBDB
- Diet
- piscivore, carnivorePBDB, for Phocidae
- Life habit
- amphibiousPBDB, for Pinnipedia
- Motility
- actively mobilePBDB, for Osteichthyes
- Environment
- marinePBDB, for Pinnipedia
Time the record covers
At least 11 million years on record.
The record covers at least 11.63 Mya to 210 ka. No occurrence read is dated outside 23.04 Mya to 14 ka.
7 occurrences of Monotherium on record, most of them in the Miocene. 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
7 occurrences- Miocene86%
- Pleistocene14%
These 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
4 formations
- Salsomaggiore Formation1
- Calvert Formation · Chesapeake Group1
- Groote Heide Formation1
- Choptank Formation · Chesapeake Group1
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The named rock units Monotherium has been recovered from, largest first. Drawn where the rock is now, not where it formed. 3 occurrences have no formation on record, which is common for older literature.
Monotherium and its relatives
MioceneWhere Monotherium and its relatives were recorded in the Miocene.
Found in the same rock
144 taxa- Phocidae3 sites
- Dugongidae2 sites
- Odontoceti2 sites
- Physeteridae2 sites
- Scaldicetus grandis2 sites
- Schizodelphis sulcatus2 sites
- "Prosthenops" xiphiodonticus1 site
- Acer1 site
- Aceratherium1 site
- Aenocyon dirus1 site
- Aetobatus1 site
- Aglaocetus longifrons1 site
- Albula1 site
- Alnus1 site
- Amaranthaceae1 site
- Ambrosia1 site
- Amphicetus1 site
- Anatinae1 site
- Ancerobranta tarabuchini1 site
- Anserinae1 site
- Apiaceae1 site
- Archaeocetus1 site
- Ardea grandis arborea1 site
- Asteracea indet.1 site
The Paleobiology Database records 7 sites for Monotherium, 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
7 references- Cenozoic vertebrate biostratigraphy of South Carolina, U.S.A. and additions to the fauna1
- Associatia de vertebrate din punctul fosilifer Sarmatian mediu Otovasca (Mun. Chisinau) si importanta oor biostratigraphfica1
- Geology and biostratigraphy of the Potomac River Cliffs at Stratford Hall, Westmoreland County, Virginia1
- The lower Serravallian cetacean fauna of Visiano (Northern Apennines, Parma, Italy)1
- Extremitatenreste einer Monchsrobbe (Phocidae, Carnivora, Mammalia) aus dem Miozan von Bocholt (Niederrhein)1
- On fossil Cetacea and Pinnipedia in the Netherlands1
- The Ancient Fauna Nebraska: or, a Description of Remains of Extinct Mammalia and Chelonia, From the Mauvaises Terres of Nebraska1
Each of the 7 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. 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 content1

Picture of Monotherium
- Source
- iDigBio
- Credit
- via iDigBio
- Licence
- not stated by the source
- Commercial use
- cannot be read from the licence given — check the record
No 3D scan of Monotherium was found in Sketchfab.
Smithsonian Open Access and MorphoSource were 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, “Monotherium”
- 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 itMonachinae through timeFormations of the MioceneThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. Van Beneden 1876