PBDB Taxon

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Ontocetus

Mammalia - Carnivora - Odobenidae

Taxonomy

Ontocetus was named by Leidy (1859) [Sepkoski's age data: T Mi-m T Mi-u].

It was synonymized subjectively with Hoplocetus by Trouessart (1898); it was considered a nomen dubium by Fordyce and de Muizon (2001).

It was assigned to Catodontidae by Cope (1867); to Sirenia by Cope (1875); to Physeterinae by Hay (1902) and Simpson (1945); to Physeteridae by Gill (1871), Palmer (1904), Kellogg (1928), Barnes (1977) and Carroll (1988); to Cetacea by Sepkoski (2002); to Odobeninae by Kohno (2006), Boessenecker and Churchill (2013), Berta (2017) and Berta et al. (2018); to Odobenidae by Ray (1975), Uhen et al. (2008), Werdelin and Peigne (2010), Berta (2018) and Albright et al. (2019); and to Odobenini by Kohno and Ray (2008), Magallanes et al. (2018), Boessenecker et al. (2018) and Biewer et al. (2020).

Species

O. emmonsi (syn. Trichecodon huxleyi, Prorosmarus alleni, Alachtherium antverpiensis, Alachtherium antwerpiensis, Alachtherium cretsii, Alachtherium africanum), Trichecodon koninckii

Synonyms

Alachtherium was named by Du Bus (1867) [Sepkoski's age data: T Plio-u]. Its type is Alachtherium cretsii.

It was synonymized subjectively with Trichechus by Trouessart (1898) and Trouessart (1904); it was synonymized subjectively with Ontocetus by Kohno and Ray (2008).

It was assigned to Odobenidae by Palmer (1904) and Kellogg (1922); to Odobenini by Deméré (1994); to Odobaenidae by Carroll (1988) and Geraads (1997); to Odobenina by McKenna and Bell (1997); to Carnivora by Sepkoski (2002); and to Odobeninae by Mitchell (1968), Repenning and Tedford (1977), Barnes (1989), Horikawa (1995), Berta (2002), Deméré et al. (2003) and Berta (2009).
Prorosmarus was named by Berry and Gregory (1906) [Sepkoski's age data: T Mi-u]. It is not extant.

It was synonymized subjectively with Ontocetus by Kohno and Ray (2008).

It was assigned to Otariidae by Berry and Gregory (1906); to Odobenidae by Kellogg (1922) and Hay (1930); to Odobaenidae by Carroll (1988); to Odobenini by Deméré (1994); to Odobenina by McKenna and Bell (1997); to Carnivora by Sepkoski (2002); and to Odobeninae by Mitchell (1968), Repenning and Tedford (1977), Barnes (1989), Horikawa (1995), Deméré et al. (2003) and Barnes (2008).
Trichecodon was named by Lankester (1865) [Sepkoski's age data: T Plio Q Plei].

It was synonymized subjectively with Trichechus by Trouessart (1898) and Trouessart (1904); it was synonymized subjectively with Odobenus by Deméré (1994); it was corrected as Trichechodon by Horikawa (1995); it was considered a nomen dubium by Rutten (1907); it was synonymized subjectively with Ontocetus by Kohno and Ray (2008).

It was assigned to Trichechidae by Lankester (1865) and Lydekker (1885); to Odobenidae by Palmer (1904) and Kellogg (1922); to Odobaenidae by Morgan (1994); to Odobenina by McKenna and Bell (1997); to Carnivora by Sepkoski (2002); and to Odobeninae by Mitchell (1968), Barnes (1989), Horikawa (1995) and Barnes (2008).
Trichecodon koninckii was named by Van Beneden (1871) [No type specimen number listed by Van Beneden (1871). Holotype original lost, but cast survives as IRSNB 2892 (Kohno, 2008).]. Its type specimen is IRSNB 2892, a tooth, and it is a 3D body fossil.

It was recombined as Trichechus koninckii by Trouessart (1898); it was recombined as Trichechus konincki by Trouessart (1904); it was synonymized subjectively with Trichecodon huxleyi by Kellogg (1922); it was recombined as Odobenus koninckii by Deméré (1994) and Deméré et al. (2003); it was considered a nomen dubium by Rutten (1907); it was misspelled as Trichechodon konincki by Dollo (1909); it was considered a nomen dubium by Repenning and Tedford (1977) and Kohno and Ray (2008).

Synonymy list

Year	Name and author
1859	Ontocetus Leidy p. 162
1865	Trichecodon Lankester p. 226 figs. Plates X-XI
1867	Ontocetus Cope p. 144
1867	Alachtherium Du Bus p. 566
1871	Ontocetus Gill p. 126
1871	Trichecodon koninckii Van Beneden p. 12
1874	Trichecodon koninckii Vanden Broeck p. 199
1875	Ontocetus Cope p. 51
1877	Trichecodon koninckii Van Beneden
1885	Trichechodon Lydekker p. 200
1885	Trichechodon konincki Lydekker p. 200
1898	Trichechus koninckii Trouessart p. 376
1902	Ontocetus Hay p. 596
1904	Alachtherium Palmer p. 87
1904	Ontocetus Palmer p. 475
1904	Trichecodon Palmer p. 688
1904	Trichechus konincki Trouessart p. 282
1906	Prorosmarus Berry and Gregory p. 444 figs. Fig. 1-2, 4a
1909	Trichechodon konincki Dollo p. 117
1922	Alachtherium Kellogg p. 101
1922	Prorosmarus Kellogg p. 101
1922	Trichecodon Kellogg p. 102
1928	Ontocetus Kellogg p. 34 figs. Table 1
1930	Prorosmarus Hay p. 559
1945	Ontocetus Simpson p. 102
1968	Alachtherium Mitchell p. 1897
1968	Prorosmarus Mitchell p. 1897
1968	Trichecodon Mitchell p. 1897
1975	Ontocetus Ray
1977	Ontocetus Barnes p. 328
1977	Alachtherium Repenning and Tedford p. 12
1977	Prorosmarus Repenning and Tedford p. 12
1988	Alachtherium Carroll
1988	Ontocetus Carroll
1988	Prorosmarus Carroll
1989	Alachtherium Barnes p. 23
1989	Prorosmarus Barnes p. 23
1989	Trichecodon Barnes p. 23
1994	Alachtherium Deméré p. 118
1994	Prorosmarus Deméré p. 119
1994	Odobenus koninckii Deméré p. 121
1994	Trichecodon Morgan
1995	Alachtherium Horikawa p. 311
1995	Prorosmarus Horikawa p. 311
1995	Trichechodon Horikawa p. 322 figs. Table 4
1997	Alachtherium Geraads p. 155
1997	Alachtherium McKenna and Bell p. 256
1997	Prorosmarus McKenna and Bell p. 256
1997	Trichecodon McKenna and Bell p. 256
2002	Alachtherium Berta p. 923
2002	Alachtherium Sepkoski
2002	Ontocetus Sepkoski
2002	Prorosmarus Sepkoski
2002	Trichechodon Sepkoski
2003	Alachtherium Deméré et al. p. 49 figs. Fig. 3.3
2003	Odobenus koninckii Deméré et al. p. 49 figs. Fig. 3.3
2003	Prorosmarus Deméré et al. p. 49 figs. Fig. 3.3
2006	Ontocetus Kohno p. 418
2008	Prorosmarus Barnes p. 535
2008	Trichecodon Barnes p. 536
2008	Ontocetus Kohno and Ray p. 44
2008	Ontocetus Uhen et al. p. 576
2009	Alachtherium Berta p. 863
2010	Ontocetus Werdelin and Peigne p. 647
2013	Ontocetus Boessenecker and Churchill p. 10 fig. 8
2017	Ontocetus Berta p. 156
2018	Ontocetus Berta p. 714 figs. Fig. 3
2018	Ontocetus Berta et al. p. 217 figs. Fig. 6
2018	Ontocetus Boessenecker et al. p. 282
2018	Ontocetus Magallanes et al. p. 30 figs. Fig. 14
2019	Ontocetus Albright et al. p. 177
2020	Ontocetus Biewer et al. figs. Figure 2

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Rank	Name	Author
kingdom	Animalia	()
—	Bilateria
—	Eubilateria	Ax 1987
—	Deuterostomia
phylum	Chordata	Haeckel 1874
subphylum	Vertebrata
superclass	Gnathostomata
—	Osteichthyes	()
subclass	Sarcopterygii	()
subclass	Dipnotetrapodomorpha	(Nelson 2006)
subclass	Tetrapodomorpha	()
—	Tetrapoda
—	Reptiliomorpha
—	Anthracosauria
subclass	Amphibiosauria	Kuhn 1967
—	Cotylosauria	()
—	Amniota
subclass	Synapsida
—	Therapsida	()
infraorder	Cynodontia	()
—	Mammaliamorpha
—	Mammaliaformes
class	Mammalia
—	Theriamorpha	(Rowe 1993)
—	Theriiformes	()

Rank	Name	Author
—	Trechnotheria
—	Cladotheria
—	Zatheria
subclass	Tribosphenida	()
subclass	Theria
—	Eutheria	()
—	Placentalia
—	Boreoeutheria
—	Laurasiatheria
—	Scrotifera
—	Ferae	()
—	Carnivoramorpha	Wyss and Flynn 1993
—	Carnivoraformes	Flynn et al.
order	Carnivora
suborder	Caniformia	Kretzoi 1943
infraorder	Canoidea	(Simpson 1931)
superfamily	Arctoidea	Flower 1869
—	Panpinnipedia	Wolsan et al. 2020
—	Pinnipedimorpha
—	Pinnipedia	()
superfamily	Otarioidea
family	Odobenidae	()
subfamily	Odobeninae
genus	Ontocetus

If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.

G. †Ontocetus Leidy 1859

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†Ontocetus emmonsi Leidy 1859

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Invalid names: Alachtherium africanum Geraads 1997 [synonym], Alachtherium antverpiensis Rutten 1907 [synonym], Alachtherium cretsii Du Bus 1867 [synonym], Prorosmarus alleni Berry and Gregory 1906 [synonym], Trichecodon huxleyi Lankester 1865 [synonym]

Invalid names: Alachtherium Du Bus 1867 [synonym], Prorosmarus Berry and Gregory 1906 [synonym], Trichecodon Lankester 1865 [synonym], Trichecodon koninckii Van Beneden 1871 [nomen dubium]

Diagnosis

No diagnoses are available

Measurements

No measurements are available

Composition:

hydroxyapatiteuc

Ontogeny:

modification of partsuc

Environment:

marinef

Locomotion:

actively mobilec

Life habit:

amphibiousf

Diet:

carnivoref

Reproduction:

viviparousf

Created:

2011-05-21 01:16:23

Modified:

2011-05-20 10:16:23

Source: f = family, c = class, uc = unranked clade

References: Carreño and Cronin 1993, Hendy et al. 2009, Kohno et al. 1995

Age range: base of the Serravallian to the top of the Rancholabrean or 13.82000 to 0.01200 Ma

Collections (69 total)

Time interval	Ma	Country or state	Original ID and collection number
Miocene - Pliocene	23.03 - 2.588	Netherlands	Alachtherium sp., Trichechus huxleyi (53929)
Neogene	23.03 - 2.58	USA (Florida)	O. emmonsi (77598 77599)
Neogene	23.03 - 2.58	USA (Georgia)	O. emmonsi (77597)
Middle Miocene - Early/Lower Pleistocene	15.97 - 0.781	Netherlands	O. emmonsi (189573)
Serravallian	13.82 - 11.62	Netherlands	Alachterium cretsii (75152)
Tortonian	11.62 - 7.246	Belgium (Antwerpen)	Trichecodon koninckii, Alachterium cretsii (66960)
Late/Upper Miocene	11.608 - 5.333	Netherlands	Alachtherium sp. (74896)
Late/Upper Hemphillian	10.3 - 4.9	USA (Florida)	O. emmonsi (60036) Trichecodon huxleyi (18532 18595)
Late/Upper Hemphillian - Zanclean	10.3 - 3.6	USA (Florida)	Trichecodon huxleyi (18535)
Early/Lower Pliocene	5.333 - 3.6	Japan (Nagano)	Alachtherium sp. (156221)
Early/Lower Pliocene	5.333 - 3.6	USA (Virginia)	O. emmonsi (57908)
Zanclean	5.333 - 3.6	USA (South Carolina)	O. emmonsi (77594)
Zanclean	5.333 - 3.6	USA (North Carolina)	O. emmonsi (49982 51591 52582 77580 77581 77582 77583 77584 77585 77586)
Zanclean	5.333 - 3.6	USA (Virginia)	O. emmonsi (77577 77578 77579)
Zanclean	5.333 - 3.6	USA (Florida)	O. emmonsi (45474) Trichecodon huxleyi (154720)
Pliocene	5.333 - 2.588	USA (North Carolina)	O. emmonsi (49983)
Pliocene	5.333 - 2.588	Belgium (Antwerpen)	Alachtherium cretsii (67029) Trichecodon koninckii, Alachtherium cretsii (67028)
Pliocene	5.333 - 2.588	USA (South Carolina)	O. emmonsi (77593 77595)
Pliocene	5.333 - 2.588	Belgium	Alachtherium antwerpiensis (116315)
Zanclean - Piacenzian	5.333 - 2.588	USA (Virginia)	Prorosmarus alleni (59155)
Zanclean - Piacenzian	5.333 - 2.588	Netherlands (Noord-Brabant)	Alachtherium cretsii (59003)
Zanclean - Piacenzian	5.333 - 2.588	Belgium (Zedelgem)	Trichecodon koninckii (67027)
Pliocene - Pleistocene	5.333 - 0.0117	Netherlands	Alachtherium sp. (87377)
Pliocene - Pleistocene	5.333 - 0.0117	USA (Georgia)	O. emmonsi (51589)
Blancan	4.9 - 1.8	USA (Florida)	O. emmonsi (19753)
Late/Upper Pliocene	3.6 - 2.588	Netherlands	Odobenus antverpiensis (116344)
Late/Upper Pliocene	3.6 - 2.588	Morocco	Alachtherium africanum (32052 32054)
Piacenzian	3.6 - 2.588	Belgium (Antwerpen)	Trichechus antverpiensis, Alachtherium cretsii, Alachtherium antwerpiensis (66958)
Piacenzian	3.6 - 2.588	USA (Florida)	O. emmonsi (32039 77600 77602 77604)
Piacenzian (interglacial)	3.6 - 2.588	USA (Florida)	O. emmonsi (77601)
Piacenzian	3.6 - 2.588	USA (South Carolina)	O. emmonsi (77591)
Piacenzian	3.6 - 2.588	United Kingdom (England)	Odobenus huxleyi (77745)
Gelasian	2.588 - 1.806	United Kingdom (England)	Odobenus huxleyi (77746) O. emmonsi (77632) Trichecodon huxleyi (48093)
Early/Lower Pleistocene	2.588 - 0.781	United Kingdom (England)	Trichechus huxleyi (77750)
Early/Lower Pleistocene	2.588 - 0.781	Netherlands	O. emmonsi (189574)
Pleistocene	2.588 - 0.0117	Netherlands	Alachtherium sp. (65174) Odobenus huxleyi (77659)
Pleistocene	2.588 - 0.0117	USA (South Carolina)	O. emmonsi (77588 206994)
Pleistocene	2.588 - 0.0117	USA (Georgia)	O. emmonsi (77596)
Calabrian	1.8 - 0.774	Belgium (Knokke-Heist)	Trichechus antverpiensis (59164)
Irvingtonian	1.8 - 0.3	USA (Florida)	O. emmonsi (20482)
Middle Pleistocene	0.774 - 0.129	Netherlands	Hippopotamus major (109704)
Middle Pleistocene	0.774 - 0.129	United Kingdom (England)	Trichechus huxleyi (58421)
Rancholabrean	0.3 - 0.012	USA (South Carolina)	O. emmonsi (206985)
Late/Upper Pleistocene	0.129 - 0.0117	USA (South Carolina)	O. emmonsi (188304)