Idiorophus

Idiorophus Temporal range: Early Miocene ~

I. patagonicus
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Artiodactyla
Infraorder:	Cetacea
Family:	Physeteridae
Genus:	†Idiorophus Kellogg, 1925
Species
I. bolzanensis Dal Piaz, 1916 I. patagonicus Lydekker, 1894
Synonyms
Apenophyseter Cabrera, 1926

Idiorophus is a genus of extinct toothed whales in the family Physeteridae. Fossils have been found in the Colhuehuapian Gaiman Formation of Argentina and the Libano Sandstone in Italy.^[1]

Description

Idirophus is thought to have been 5.42–6.61 meters (17.8–21.7 ft) long. Discovered in rocks dated to the early Miocene, it is thought to be one of the oldest sperm whales.^[2] The teeth of Idiorophus were similar in size to those of the modern orca. This species is thought to be a highly predatory sperm whale. The teeth are covered in enamel and show wear from eating large prey.^[3]

Taxonomy

It has been proposed that Idiorophus be placed in the subfamily Hoplocetinae, alongside Scaldicetus, Diaphorocetus, and Hoplocetus.^[4]

References

^ "Idiorophus at Fossilworks". Archived from the original on 2021-12-12. Retrieved 2021-12-17.
^ Paolucci, F.; Buono, M. R.; Fernández, M. S. (2025). "Awakening Patagonia's sleeping sperm whale: a new description of the Early Miocene Idiorophus patagonicus (Odontoceti, Physeteroidea)". Papers in Palaeontology. 11 (2). e70007. doi:10.1002/spp2.70007. The lower and upper boundaries of the TL estimated for Idiorophus are 5.42 m and 6.61 m, respectively
^ Hampe, O. (2006). "Middle/late Miocene hoplocetine sperm whale remains (Odontoceti: Physeteridae) of North Germany with an emended classification of the Hoplocetinae". Fossil Record. 9 (1): 61–86. Bibcode:2006FossR...9...61H. doi:10.1002/mmng.200600002.
^ Toscano, A.; Abad, M.; Ruiz, F.; Muñiz, F.; Álvarez, G.; García, E.; Caro, J. A. (2013). "Nuevos Restos de Scaldicetus (Cetacea, Odontoceti, Physeteridae) del Mioceno Superior, Sector Occidental de la Cuenca del Guadalquivir (Sur de España)" [New Remains of Scaldicetus (Cetacea, Odontoceti, Physeteridae) from the Upper Miocene, Western Sector of the Guadalquivir Basin]. Revista Mexicana de Ciencias Geológicas (in Spanish). 30 (2).

†Agorophius †Ankylorhiza †Archaeodelphis †Argyrocetus †Ashleycetus †Caolodelphis †Chilcacetus †Enigmatocetus †Eoplatanista †Inticetus †Macrodelphinus †Microcetus †Mirocetus †Neosqualodon †Olympicetus †Papahu †Patriocetus †Phoberodon †Phococetus †Prosqualodon †Sachalinocetus †Simocetus †Sulakocetus †Tangaroasaurus
†Xenorophidae	Albertocetus Cotylocara Echovenator Inermorostrum Xenorophus
†Waipatiidae	Awamokoa Ediscetus Nihohae Nihoroa Otekaikea Urkudelphis Waipatia
†Squalodontidae	Eosqualodon Squalodon
†Squaloziphiidae	Crisocetus? Squaloziphius Yaquinacetus
†Eurhinodelphinidae	Ceterhinops Eurhinodelphis Iniopsis Mycteriacetus Phocaenopsis Schizodelphis Vanbreenia Xiphiacetus Ziphiodelphis
Crown-Odontoceti	see below↓

Crown-Odontoceti

Physeteroidea

†Acrophyseter †Albicetus †Brygmophyseter †Eudelphis †Hoplocetus †Livyatan †Miophyseter †Rhaphicetus †Scaldicetus †Zygophyseter
Kogiidae	†Aprixokogia Kogia †Koristocetus †Nanokogia †Platyscaphokogia †Pliokogia †Praekogia †Scaphokogia †Thalassocetus?
Physeteridae	†Aulophyseter †Cozzuoliphyseter †Diaphorocetus †Idiophyseter †Idiorophus †Orycterocetus Physeter †Physeterula †Placoziphius †Thalassocetus?

Platanistoidea

†Aondelphis †Dolgopolis †Ensidelphis †Perditicetus †Eurhinodelphinidae? †Squalodontidae? †Waipatiidae?
†Allodelphinidae?	Allodelphis Arktocara Goedertius Ninjadelphis Zarhinocetus
†Squalodelphinidae?	Furcacetus Huaridelphis Macrosqualodelphis Medocinia Notocetus Phocageneus Squalodelphis
Platanistidae	†Araeodelphis †Dilophodelphis †Grimadelphis †Pachyacanthus? †Pebanista Platanista †Pomatodelphis †Prepomatodelphis †Zarhachis?

Ziphiidae

†Aporotus †Beneziphius †Caviziphius †Chavinziphius †Chimuziphius †Choneziphius †Dagonodum †Globicetus †Imocetus †Messapicetus †Nazcacetus †Nenga †Ninoziphius †Notoziphius †Pterocetus Tasmacetus †Tusciziphius †Xhosacetus †Ziphirostrum
Berardiinae	†Archaeoziphius Berardius †Microberardius
Ziphiinae	†Izikoziphius Ziphius
Hyperoodontinae	†Africanacetus Hyperoodon †Ihlengesi Indopacetus Mesoplodon

Delphinida	see below↓

Delphinida

†Albireo †Atocetus †Brevirostrodelphis †Cammackacetus †Delphinodon †Hadrodelphis †Herbeinodelphis †Liolithax †Lophocetus †Macrokentriodon †Miminiacetus †Odobenocetops †Pictodelphis †Pithanodelphis †Tagicetus †Westmorelandelphis
†Kentriodontidae	Belonodelphis? Kampholophos Kentriodon Platysvercus Sophianacetus Rudicetus Wimahl
Lipotidae	Lipotes †Parapontoporia †Prolipotes

Inioidea

†Awadelphis
Iniidae	†Brujadelphis †Goniodelphis Inia †Ischyrorhynchus †Isoninia? †Isthminia †Kwanzacetus †Meherrinia †Plicodontinia †Saurocetes
Pontoporiidae	†Atocetus? †Auroracetus †Brachydelphis †Piscorhynchus †Pliopontos †Pontistes †Protophocaena †Samaydelphis †Scaldiporia †Stenasodelphis Pontoporia

Delphinoidea

Monodontidae	†Bohaskaia †Casatia Delphinapterus †Denebola †Haborodelphis Monodon
Phocoenidae	†Archaeophocaena †Australithax †Haborophocoena †Lomacetus †Miophocaena Neophocaena †Numataphocoena Phocoena Phocoenoides †Piscolithax †Pterophocaena? †Semirostrum †Septemtriocetus

Delphinidae

†Arimidelphis †Australodelphis †Eodelphinus †Etruridelphis †Hemisyntrachelus Lagenorhynchus Leucopleurus †Norisdelphis Orcinus †Platalearostrum †Pliodelphis †Pterophocaena?
Lissodelphininae	Aethalodelphis Cephalorhynchus Lissodelphis
Delphininae	Delphinus Lagenodelphis Sotalia Sousa Stenella Tursiops
Globicephalinae	Feresa Globicephala Grampus Orcaella Peponocephala Pseudorca Steno

Description

Taxonomy

References

Further reading