PBDB Taxon

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Hyrachyidae

Mammalia - Perissodactyla - Hyrachyidae

Taxonomy

Hyrachyidae was named by Osborn (1892). It is not extant. Its type is Hyrachyus.

It was reranked as the subfamily Hyrachyinae by Hay (1902), Peterson (1919), Radinsky (1966).

It was assigned to Hyracodontidae by Hay (1902), Peterson (1919); to Helaletidae by Radinsky (1966); and to Rhinocerotoidea by Holbrook (1999).

Subtaxa

Hyrachyus (syn. Metahyrachyus, Colonoceras, Chasmotherium, Ephyrachyus) (type genus), Hyrachyus douglassi (syn. Hyrachyus priscus), Subhyrachyus

Synonyms

Hyrachyus priscus was named by Douglass (1903). Its type specimen is CM 784, a partial skull (the greater part of the mandible with all the post-canines except P1 , the anterior part of the skull with incisors and premolars, and the atlas), and it is a 3D body fossil. Its type locality is Sage Creek Formation, which is in a Bridgerian terrestrial horizon in Montana.

It was replaced with Hyrachyus douglassi by Wood (1934).
Hyrachyus douglassi was named by Wood (1934) [replacement for "H. priscus" Douglass 1903]. Its type specimen is CM 784 and is a 3D body fossil. Its type locality is Sage Creek Formation, which is in a Bridgerian terrestrial horizon in Montana.

It was considered a nomen dubium by Radinsky (1967), Radinsky (1967).

Synonymy list

Year	Name and author
1892	Hyrachyidae Osborn
1902	Hyrachyinae Hay p. 638
1903	Hyrachyus priscus Douglass p. 156 figs. FIg. 2
1919	Hyrachyinae Peterson p. 127
1934	Hyrachyus douglassi Wood p. 208 figs. Figures 23 and 24
1966	Hyrachyinae Radinsky p. 633
1999	Hyrachyidae Holbrook p. 346

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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

Rank	Name	Author
—	Mammaliaformes
class	Mammalia
—	Cladotheria
—	Zatheria
subclass	Tribosphenida	()
subclass	Theria
—	Eutheria	()
—	Placentalia
—	Boreoeutheria
—	Laurasiatheria
—	Scrotifera
—	Euungulata
—	Panperissodactyla
superorder	Perissodactylamorpha
order	Perissodactyla	()
—	Tapiromorpha	(Haeckel 1873)
—	Ceratomorpha	(Wood 1937)
superfamily	Rhinocerotoidea
family	Hyrachyidae	Osborn 1892
family	Hyrachyidae	Osborn 1892

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.

Fm. †Hyrachyidae Osborn 1892

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G. †Hyrachyus Leidy 1871

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†Hyrachyus crista Qi 1987

†Hyrachyus eximius Leidy 1871

Invalid names: Hyrachyus hypostylus Wood 1934 [synonym], Hyrachyus imperialis Osborn et al. 1878 [synonym], Hyrachyus princeps Marsh 1872 [synonym], Metahyrachyus troxelli Wood 1934 [synonym]

†Hyrachyus lunanensis Huang and Qi 1982

†Hyrachyus metalophus Chow and Qi 1982

†Hyrachyus minor Huang and Qi 1982

†Hyrachyus modestus Leidy 1870

Invalid names: Colonoceras agrestis Marsh 1873 [synonym], Ephyrachyus cristalophus Wood 1934 [synonym], Hyrachyus agrarius Leidy 1871 [synonym], Hyrachyus agrestis Leidy 1871 [synonym], Hyrachyus crassidens Osborn et al. 1878 [synonym], Lophiodon affinis Marsh 1871 [synonym], Lophiodon bairdianus Marsh 1871 [synonym], Metahyrachyus bicornutus Troxell 1922 [synonym]

†Hyrachyus nanus Marsh 1871

†Hyrachyus neimongoliensis Qi 1987

†Hyrachyus paradoxus Osborn 1878

†Hyrachyus tongi Huang and Wang 2002

Invalid names: Chasmotherium Rutimeyer [synonym], Colonoceras Marsh 1873 [synonym], Ephyrachyus Wood 1934 [synonym], Metahyrachyus Troxell 1922 [synonym]

G. †Subhyrachyus Gabunia 1999

Invalid names: Hyrachyus douglassi Wood 1934 [nomen dubium]

Diagnosis

No diagnoses are available

Measurements

No measurements are available

Composition:

phosphaticsubp

Environment:

terrestrialsubc

Locomotion:

actively mobilec

Life habit:

ground dwellingsubo

Diet:

browsersubo

Reproduction:

viviparoussubc

Created:

2005-08-31 15:03:12

Modified:

2005-08-31 17:03:12

Source: subo = suborder, subc = subclass, c = class, subp = subphylum

References: Colbert and Schoch 1998, Ji et al. 2002, Hendy et al. 2009, Carroll 1988, Lillegraven 1979

Age range: base of the Wasatchian to the top of the Late/Upper Eocene or 55.80000 to 33.90000 Ma

Collections (166 total)

Time interval	Ma	Country or state	Original ID and collection number
Ypresian - Lutetian	56.0 - 41.3	France (Languedoc-Roussillon Region)	Chasmotherium sp. (31717)
Ypresian - Lutetian	56.0 - 41.3	France (Occitanie)	Hyrachyus stehlini (195457)
Eocene - Oligocene	56.0 - 23.03	China (Henan)	Hyrachyus sp. (42565)
Wasatchian	55.8 - 50.3	USA (Wyoming)	Hyrachyus modestus (15710 15839) Hyrachyus sp. (16057 16059)
Early/Lower Eocene	55.8 - 48.6	Germany (Sachsen-Anhalt)	Chasmotherium minimum (45749)
Early/Lower Eocene	55.8 - 48.6	China (Nei Mongol)	Hyrachyus crista (175354 226243) Hyrachyus neimongoliensis (174920)
MP 10	55.8 - 48.6	United Kingdom (England)	Hyrachyus stehlini (41840)
Wasatchian - Bridgerian	55.8 - 46.2	USA (Wyoming)	Hyrachyus modestus (15463)
Bridgerian	50.3 - 46.2	USA (Utah)	Hyrachyus modestus (16396)
Bridgerian	50.3 - 46.2	USA (Nevada)	Hyrachyus affinis, Hyrachyus modestus (16218)
Bridgerian	50.3 - 46.2	USA (Texas)	Hyrachyus sp. (16195)
Bridgerian	50.3 - 46.2	USA (Montana)	Hyrachyus priscus (16401)
Bridgerian	50.3 - 46.2	USA (Wyoming)	Hyrachyus affinis (16194 16226 16275 16281 16283) Hyrachyus affinis, Hyrachyus agrarius, Hyrachyus modestus, Hyrachyus nanus (16228) Hyrachyus affinis, Hyrachyus eximius (16234) Hyrachyus affinis, Hyrachyus modestus (16205 16284) Hyrachyus affinis, Metahyrachyus troxelli (16193) Hyrachyus agrarius, Hyrachyus nanus (106325) Hyrachyus agrestis (16136) Hyrachyus eximius (16135 16138 16200 16206 16207 16235 16244 16278 16407 16413 16415 16428 16438 16444 202162) Hyrachyus eximius, Hyrachyus modestus (16213 16502 16647) Hyrachyus modestus (16198 16201 16219 16227 16232 16290 16292 16355 16359 16360 16362 16364 16366 16385 16386 16409 16418 16483 16484 16491 16493 202160 202163) Hyrachyus princeps (16288 16420) Hyrachyus sp. (15837 16088 16092 16093 16095 16096 16098 16100 16103 16104 16106 16108 16109 16113 16114 16116 16121 16123 16129 16131 16132 16256 16257 16260 16268 16270 16273 16274 16287 16296 16301 16302 16305 16308 16309 16310 16313 16314 16315 16317 16318 16327 16330 16331 16335 16342 16346 16363 16394 27269 129895) Lophiodon modestus (16414)
Bridgerian	50.3 - 46.2	USA (California)	Hyrachyus sp. (16422)
Bridgerian	50.3 - 46.2	USA (Colorado)	Hyrachyus modestus (16239 16240 16242)
Lutetian	47.8 - 41.3	Germany (Sachsen-Anhalt)	Chasmotherium minimum (45739 45741 45742 45745 45747 45750 45751) Chasmotherium minimum, Hyrachyus minimus (13322 44999 45000 45001) Hyrachyus minimus (45002)
Lutetian	47.8 - 41.3	Spain (Zamora)	Chasmotherium minimum (41308)
Lutetian	47.8 - 41.3	France (Drome)	Chasmotherium sp. (177494)
Lutetian	47.8 - 41.3	Jamaica	Hyrachyus sp. (5241)
Lutetian	47.8 - 41.3	United Kingdom (England)	Hyrachyus stehlini (41847)
Lutetian - Bartonian	47.8 - 38.0	Switzerland (Baselland)	Hyrachyus stehlini (31723)
Middle Eocene	47.8 - 37.71	China (Henan)	Hyrachyus sp. (175802)
Middle Eocene	47.8 - 37.71	China (Shandong)	Hyrachyus modestus (175581) Hyrachyus sp., Hyrachyus modestus, Hyrachyus metalophus (175583)
Middle Eocene	47.8 - 37.71	USA (Oregon)	Hyrachyus sp. (16202)
Middle Eocene	47.8 - 37.71	USA (Wyoming)	Hyrachyus agrarius (81455)
Middle Eocene	47.8 - 37.71	China (Shanxi)	Hyrachyus tongi (174907)
Middle Eocene	47.8 - 37.71	China (Yunnan)	Hyrachyus lunanensis, Hyrachyus minor (174964)
Middle Eocene - Late/Upper Eocene	47.8 - 33.9	Japan (Hyogo)	Hyrachyus sp. (74903)
Early/Lower Uintan	46.2 - 39.7	USA (Texas)	Hyrachyus modestus (16586)
Uintan	46.2 - 39.7	USA (Utah)	Hyrachyus eximius (16655)
Uintan	46.2 - 39.7	USA (Wyoming)	Hyrachyus eximius (16556 16565 16576 16648)
Bartonian	41.3 - 38.0	Switzerland (Baselland)	Chasmotherium cartieri (31721 31722) Chasmotherium cartieri, Hyrachyus minimus (31720)
Bartonian	41.3 - 38.0	France (Languedoc-Roussillon Region)	Chasmotherium cartieri, Chasmotherium depereti (31736) Chasmotherium depereti (183350)
Bartonian	41.3 - 38.0	France (Nord-Pas-de-Calais-Picardie)	Chasmotherium cartieri (177582)
Late/Upper Eocene	37.2 - 33.9	Germany (Sachsen-Anhalt)	Hyrachyus minimus (45003)