Monotherium Temporal range: Miocene PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Carnivora
Clade:	Pinnipedia
Family:	Phocidae
Genus:	†Monotherium van Beneden, 1874
Species
M. delognii (type) van Beneden, 1874

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.

Species

The type and only species of Monotherium is M. delognii, described from the Tortonian-age Diest Formation of Antwerp, Belgium, on the basis of the lectotype pelvis IRSNB 1153-M257a, b.^[1]

Monotherium affine and M. aberratum were previously assigned to this genus, as well as "Phoca" gaudini, but the former two are now considered a distinct genus, Frisiphoca, while gaudini has been renamed Noriphoca. The middle Miocene phocid "Phoca" wymani Leidy, 1853 was assigned to Monotherium by Ray (1976), but was considered a monachine of uncertain affinities.^[2]^[3]^[4]

References

^ P. J. Van Beneden. 1874. Les phoques fossiles du bassin d'Anvers. Bulletins de l'Academie Royale des Sciences, des Lettres et des Beaux-Arts de Belgique 41:783-803
^ J. Leidy. 1854. The ancient fauna of Nebraska 1-126
^ C. E. Ray. 1976. Phoca wymani and other Tertiary seals (Mammalia: Phocidae) described from the eastern seaboard of North America. Smithsonian Contributions to Paleobiology 28:1-33
^ Leonard Dewaele; Olivier Lambert; Stephen Louwye (2018). "A critical revision of the fossil record, stratigraphy and diversity of the Neogene seal genus Monotherium (Carnivora, Phocidae)". Royal Society Open Science. 5 (5): 171669. doi:10.1098/rsos.171669.

Genera of pinnipeds and their stem-allies

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Suborder: Caniformia
Infraorder: Arctoidea

Pan-Pinnipedia

†Amphicynodontidae	Allocyon Amphicticeps Amphicynodon Drassonax Kolponomos Pachycynodon Parictis Wangictis
†Semantoridae	Necromites Potamotherium Puijila Semantor

Pinnipedimorpha

†Enaliarctos

Pinnipediformes

†Pacificotaria
†Pinnarctidion
†Pteronarctos

Pinnipedia

Phocidae

†Devinophoca

Monachinae

†Magnotherium
Monachini	†Afrophoca †Auroraphoca †Messiphoca Monachus Neomonachus †Eomonachus †Noriphoca †Palmidophoca †Pliophoca †Pontophoca †Pristiphoca †Terranectes
Miroungini	†Callophoca Mirounga
Lobodontini	†Acrophoca †Australophoca †Hadrokirus †Homiphoca Hydrurga Leptonychotes Lobodon Ommatophoca †Piscophoca †Properiptychus †Virginiaphoca

Phocinae

†Cryptophoca †Frisiphoca †Kawas †Leptophoca †Monachopsis †Monotherium †Phocanella †Prophoca †Sarmatonectes
Erignathini	Erignathus †Platyphoca
Cystophorini	Cystophora †Miophoca †Pachyphoca
Phocini	†Batavipusa †Gryphoca Halichoerus Histriophoca †Nanophoca Pagophilus Phoca †Planopusa †Praepusa Pusa

Otarioidea	see below↓

Otarioidea

†Desmatophocidae

Allodesmus
Atopotarus
Desmatophoca
Eodesmus

Odobenidae

†Archaeodobenus
†Imagotaria
†Kamtschatarctos
†Nanodobenus
†Neotherium
†Osodobenus
†Pelagiarctos
†Pontolis
†Proneotherium
†Prototaria
†Pseudotaria
†Titanotaria

Neodobenia

†Dusignathinae	Dusignathus Gomphotaria
Odobeninae	†Aivukus Odobenus †Ontocetus †Pliopedia †Protodobenus †Valenictus

Panotariidae

†Eotaria

Otariidae

Callorhinae

Callorhinus
†Pithanotaria

Otariinae

†Thalassoleon
Zalophini	Eumetopias †Oriensarctos †Proterozetes Zalophus
Otariini	Arctocephalus Arctophoca †Hydrarctos Neophoca Otaria Phocarctos

Lists
List of pinnipeds List of fossil pinnipedimorphs