Rhinocerotoidea

Rhinocerotoids Temporal range: c.50–0  Ma PreꞒ Ꞓ O S D C P T J K Pg N Eocene to Recent
White rhinoceros (Rhinocerotidae) Paraceratherium (Paraceratheriidae) Hyracodon (Hyracodontidae) Amynodon (Amynodontidae)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Infraclass:	Placentalia
Order:	Perissodactyla
Clade:	Tapiromorpha
Suborder:	Ceratomorpha
Superfamily:	Rhinocerotoidea Gray, 1821
Families and genera
Generally recognized families † Amynodontidae † Hyracodontidae † Paraceratheriidae Rhinocerotidae Sometimes recognized † Eggysodontidae (or subfamily in Hyracodontidae) † Forstercooperiidae (or subfamily in Paraceratheriidae) Incertae sedis genera † Armania † Breviodon ? † Fouchia † Hyrachyus † Indolophus † Minchenoletes † Selanaletes † Teletaceras † Triplopus † Uintaceras † Yimengia

Rhinocerotoidea is a superfamily of perissodactyls which includes the living rhinoceroses and their extinct relatives. In addition to rhinoceroses (Rhinocerotidae), Rhinocerotoidea also comprises at least three extinct families: the Amynodontidae, Hyracodontidae, and Paraceratheriidae. The relationships between the different groups are not well resolved, and two additional extinct families are sometimes recognized, the Eggysodontidae and Forstercooperiidae.

Extinct non-rhinocerotid members of the group are sometimes considered rhinoceroses in a broad sense. Although the term 'rhinoceroses' is sometimes used to refer to all of these, a less ambiguous vernacular term for this group is 'rhinocerotoids'. Rhinocerotidae are sometimes called "true rhinoceroses" to distinguish them from other rhinocerotoids.

Internal classification

Families

Rhinocerotoidea has traditionally been divided into three families: the extant Rhinocerotidae (true rhinoceroses) and the extinct Amynodontidae (swamp rhinoceroses) and Hyracodontidae (running rhinoceroses). ^[1] Phylogenetic analyses often recover the traditional Hyracodontidae as paraphyletic; the giant paraceratheres, historically considered part of the family, are therefore generally recognized as the distinct family Paraceratheriidae. ^{[2] [3] [4] [5]}

Whether additional families of rhinocerotoids are recognized depends on the analysis. Historically, the basal rhinocerotoid Hyrachyus and similar forms have sometimes been placed in a family named Hyrachyidae, ^[6] though recent analyses do not recover Hyrachyus in a consistent position or group. ^{[3] [4] [5]} Eggysodonts are variously separated into the distinct family Eggysodontidae ^[3] or retained within Hyracodontidae; ^[5] whether eggysodonts and hyracodonts form a monophyletic group varies between analyses. ^{[3] [4] [5]} Forstercooperia and similar forms are treated either as paraceratheres ^[7] or separated into the distinct family Forstercooperiidae. ^{[4] [5]} Analyses similarly vary in whether forstercooperiids and paraceratheres are recovered as a monophyletic group or not. ^{[3] [4] [5]}

Phylogeny

Recent analyses do not reach a consensus on interrelationships within Rhinocerotoidea. The cladograms below follow phylogenetic analyses by Bai et al. (2020), ^[4] Deng et al. (2021), ^[8] Veine-Tonizzo et al. (2023), ^[3] and Lu et al. (2026). ^[5]

Topology A: Bai et al. (2020) [4] Rhinocerotoidea Indolophus Breviodon Fouchia Minchenoletes Triplopus cubitalus Yimengia Rhinocerotoidea Hyrachyus Uintaceras Teletaceras Selenaletes Triplopus? youjingensis Hyracodontidae ⊞ Ephyrachyus Prohyracodon Ardynia Hyracodon Epitriplopus Triplopides ⊟ Forstercooperiidae ⊞ Forstercooperia Gobicerops Pappaceras ⊟ Amynodontidae ⊞ Caenolophus Proeggysodon Rostriamynodon Sharamynodon Amynodon Cadurcodon Metamynodon Paramynodon ⊟ Eggysodon Paraceratheriidae ⊞ Juxia Paraceratherium Urtinotherium ⊟ Rhinocerotidae ⊞ Trigonias Subhyracodon Menoceras Rhinoceros ⊟ (sensu stricto) (sensu lato)

Topology B: Deng et al. (2021) [8] Rhinocerotoidea Hyrachyus eximius Amynodontidae ⊞ Amynodon advenus Rostriamynodon grangeri ⊟ Triplopus cubitalis Hyracodontidae ⊞ Epitriplopus uintensis Hyracodon nebraskensis Triplopides rieli ⊟ Uintaceras radinskyi Rhinocerotidae ⊞ Teletaceras borissiaki Trigonias osborni Subhyracodon occidentalis Rhinoceros unicornis Ceratotherium simum Coelodonta antiquitatis ⊟ Pappaceras confluense Forstercooperia totadentata Paraceratheriidae ⊞ Juxia sharamurenensis Urtinotherium intermedium Turpanotherium yagouense Dzungariotherium orgosense Aralotherium prohorovi Paraceratherium grangeri Paraceratherium huangheense Paraceratherium asiaticum Paraceratherium bugtiense Paraceratherium lepidum Paraceratherium linxiaense ⊟

Topology C: Veine-Tonizzo et al. (2023) [3] Rhinocerotoidea Hyrachyus eximius Hyrachyus princeps Rhinocerotidae ⊞ Trigonias osborni Ronzotherium filholi Aceratherium incisivum ⊟ Eggysodontidae ⊞ Proeggysodon qiui Triplopus obliquidens Eggysodon osborni Allacerops turgaica ⊟ Unnamed clade Pappaceras confluens Uintaceras radinskyi Teletaceras radinskyi Hyracodon nebraskensis Paraceratheriidae ⊞ Urtinotherium intermedium Paraceratherium bugtiense Paraceratherium transouralicum ⊟ " Pappaceras " meiomenus Amynodontidae ⊞ Rostriamynodon grangeri Amynodon advenus Sharamynodon mongoliensis Metamynodontini Paramynodon birmanicus Megalamynodon regalis Sellamynodon zimborensis Metamynodon planifrons Cadurcodontini " Amynodon " reedi Zaisanamynodon borisovi Zaisanamynodon protheroi Sianodon gaowangouensis Amynodontopsis bodei Amynodontopsis aff. bodei Cadurcotherium minus Cadurcotherium cayluxi Cadurcodon bahoensis Cadurcodon maomingensis Cadurcodon ardynensis Cadurcodon kazakademius ⊟

Topology D: Lu et al. (2026) [5] Rhinocerotoidea Indolophus Fouchia Breviodon acares Minchenoletes erlianensis Yimengia Triplopus cubitalus Ephyrachyus Hyrachyus modestus Uintaceras radinskyi Selanaletes scopaeus Hyracodontidae Allaceropinae ⊞ Guangnanodon youngi Megacanodon dongxiangense Allacerops ningdongica "Moissac materials" Allacerops turgaica ⊟ Eggysodontinae ⊞ Eggysodon lingwuensis Eggysodon gaudryi Eggysodon osborni " Allacerops " minor Proeggysodon qiui ⊟ Hyracodontinae ⊞ Hyracodon nebraskensis Prohyracodon orientale Ardynia Triplopides rieli Epitriplopus uintensis Ilianodon lunanensis " Hyracodon " priscidens " Prohyracodon " meridionale ⊟ Rhinocerotidae ⊞ Trigonias Subhyracodon occidentalis Rhinoceros unicornis Menoceras arikarense ⊟ Teletaceras Forstercooperiidae ⊞ Pappaceras Forstercooperia Gobicerops ⊟ Paraceratheriidae ⊞ Juxia Urtinotherium Paraceratherium ⊟ Amynodontidae ⊞ Caenolophus promissus Rostriamynodon grangeri Sharamynodon mongoliensis Amynodon Paramynodon Metamynodon Cadurcodon ⊟

References

1. Osborn, Henry Fairfield (1898). "The Extinct Rhinoceroses". Memoirs of the American Museum of Natural History. 1 (3): 80.
2. Haibing Wang; Bin Bai; Jin Meng; Yuanqing Wang (2016). "Earliest known unequivocal rhinocerotoid sheds new light on the origin of Giant Rhinos and phylogeny of early rhinocerotoids". Scientific Reports. 6: Article number 39607. doi:10.1038/srep39607.
3. Veine-Tonizzo, Lea; Tissier, Jérémy; Bukhsianidze, Maia; Vasilyan, Davit; Becker, Damien (2023). "Cranial morphology and phylogenetic relationships of Amynodontidae Scott and Osborn, 1883 (Perissodactyla, Rhinocerotoidea)". Comptes Rendus. Palevol. 22 (8): 109–142. doi:10.5852/cr-palevol2023v22a8.
4. Bai, B.; Meng, J.; Zhang, C.; Gong, Y.-X.; Wang, Y.-Q. (2020). "The origin of Rhinocerotoidea and phylogeny of Ceratomorpha (Mammalia, Perissodactyla)". Communications Biology. 3 (1): 509. doi: 10.1038/s42003-020-01205-8 . PMC   7490376 . PMID   32929169.
5. Lu, Xiaokang; Deng, Tao; Sun, Boyang; Sun, Danhui; Li, Shijie (2026). "A new rhinocerotoid (Mammalia, Perissodactyla) from the early Oligocene of Ningdong, China, and its phylogenetic implications" . Journal of Mammalian Evolution. 32 (4): 47. doi:10.1007/s10914-025-09791-2. ISSN   1573-7055.
6. Bai, Bin; Meng, Jin; Wang, Yuan-Qing; Wang, Hai-Bing; Holbrook, Luke (2017). "Osteology of The Middle Eocene Ceratomorph Hyrachyus modestus (Mammalia, Perissodactyla)" . Bulletin of the American Museum of Natural History. 413: 1–70. doi:10.1206/0003-0090-413.1.1. ISSN   0003-0090.
7. Wang, Hai-Bing; Bai, Bin; Meng, Jin; Wang, Yuan-Qing (2018). "A New Species of Forstercooperia (Perissodactyla: Paraceratheriidae) from Northern China with a Systematic Revision of Forstercooperiines". American Museum Novitates. 3897 (3897): 1–41. doi:10.1206/3897.1. ISSN   0003-0082.
8. Deng, Tao; Lu, Xiaokang; Wang, Shiqi; Flynn, Lawrence J.; Sun, Danhui; He, Wen; Chen, Shanqin (2021). "An Oligocene giant rhino provides insights into Paraceratherium evolution". Communications Biology. 4 (1): 639. doi:10.1038/s42003-021-02170-6. ISSN   2399-3642. PMC   8211792 . PMID   34140631.