# List of pelycosaurs

This list of pelycosaurs is an attempt to create a comprehensive listing of all genera that have ever been included in the synapsida excluding therapsida and purely vernacular terms. The list includes all commonly accepted genera, but also genera that are now considered invalid, doubtful (nomina dubia), or were not formally published (nomina nuda), as well as junior synonyms of more established names, and genera that are no longer considered pelycosaurs.
The list currently contains 83 generic names.

## Naming conventions and terminology

Naming conventions and terminology follow the International Code of Zoological Nomenclature. Technical terms used include:
* Junior synonym: A name which describes the same taxon as a previously published name. If two or more genera are formally designated and the type specimens are later assigned to the same genus, the first to be published (in chronological order) is the senior synonym, and all other instances are junior synonyms. Senior synonyms are generally used, except by special decision of the ICZN, but junior synonyms cannot be used again, even if deprecated. Junior synonymy is often subjective, unless the genera described were both based on the same type specimen.
* Nomen nudum (Latin for "naked name"): A name that has appeared in print but has not yet been formally published by the standards of the ICZN. Nomina nuda (the plural form) are invalid, and are therefore not italicized as a proper generic name would be. If the name is later formally published, that name is no longer a nomen nudum and will be italicized on this list. Often, the formally published name will differ from any nomina nuda that describe the same specimen.
* Nomen oblitum (Latin for "forgotten name"): A name that has not been used in the scientific community for more than fifty years after its original proposal.
* Preoccupied name: A name that is formally published, but which has already been used for another taxon. This second use is invalid (as are all subsequent uses) and the name must be replaced. As preoccupied names are not valid generic names, they will also go unitalicized on this list.
* Nomen dubium (Latin for "dubious name"): A name describing a fossil with no unique diagnostic features. As this can be an extremely subjective and controversial designation, this term is not used on this list.

## List

| Genus | Authors | Year | Status | Age | Location | Notes |
| Aerosaurus | Romer | 1937 | Valid. | Late Carboniferous - Lower Permian | United States of America | |
| Angelosaurus | Olson Beerbower | 1953 | Valid. | Upper Permian | United States of America | |
| Anglosaurus | Bruner | 1991 | Sic | N/A | N/A | Incorrect spelling for Angelosaurus |
| Apsisaurus | Laurin | 1991 | Valid. | Lower Permian | United States of America | Formerly assigned as a "eosuchian" diapsid. |
| Archaeobelus | Cope | 1877 | Syn. | N/A | N/A | Synonym of Clepsydrops |
| Archaeothyris | Reisz | 1972 | Valid. | Upper Carboniferous | United States of America | |
| Archaeovenator | Reisz Dilkes | 2003 | Valid. | Upper Carboniferous | United States of America | |
| Arribasaurus | Williston | 1914 | Syn. | N/A | N/A | Synonym of Ophiacodon |
| Baldwinonus | Romer Price | 1940 | Valid. | Late Carboniferous - Early Permian | United States of America | |
| Basicranodon | Vaughn | 1958 | Syn. | Lower Permian | United States of America | Synonym of Mycterosaurus |
| Bathyglyptus | Case | 1911 | Syn. | N/A | N/A | Synonym of Dimetrodon |
| Bathygnathus | Leidy | 1854 | Valid. | Lower Permian | United States of America | |
| Brachycnemius | Williston | 1911 | Syn. | N/A | N/A | Synonym of Edaphosaurus |
| Callibrachion | Boule Glangeau | 1893 | Syn. | N/A | N/A | Synonym of Haptodus |
| Casea | Williston | 1910 | Valid. | Lower Permian | France and United States of America | |
| Caseoides | Olson Beerbower | 1953 | Valid. | Lower Permian | United States of America | |
| Caseopsis | Olson | 1962 | Valid. | Upper Permian | United States of America | |
| Clepsydrops | Cope | 1875 | Valid. | Late Carboniferous | United States of America | |
| Colobomycter | Vaughn | 1958 | Valid. | Lower Permian | United States of America | It is a protorothyridid eureptile |
| Cotylorhynchus | Stovall | 1937 | Valid. | Lower Permian | United States of America | |
| Cryptovenator | Fröbisch Schoch Müller Schindler Schweiss | 2011 | Valid. | Late Carboniferous | Germany |
| Ctenorhachis | Hook Hotton | 1991 | Valid. | Upper Permian | United States of America | |
| Ctenospondylus | Romer | 1936 | Valid. | Lower Permian | United States | |
| Cutleria | Lewis Vaughn | 1965 | Valid. | Early Permian | United States of America | |
| Delorhynchus | Fox | 1962 | Valid. | Lower Permian | United States of America | Originally descript as a pelycosaur, but probably a parareptile |
| Datheosaurus | Schroeder | 1905 | Syn. | N/A | N/A | Synonym of Haptodus |
| Dimacrodon | Olson Beerbower | 1953 | Valid? | Lower Permian | United States | Originally descript as an anomodont therapsid by Olson & Beerbower (1953) and Olson (1962), it lacks any diagnostic features of anomodonts and rather represent pelycosaur-grade synapsids |
| Dimetrodon | Cope | 1878 | Valid. | Early Permian - Middle Permian | United States of America and Germany | |
| Diopaeus | Cope | 1892 | Syn. | N/A | N/A | Synonym of Ophiacodon |
| Echinerpeton | Reisz | 1972 | Valid. | Upper Carboniferous | Canada | |
| Edaphosaurus | Cope | 1882 | Valid. | Late Carboniferous - Lower Permian | Czech Republic and United States of America | |
| Elcabrosaurus | Case | 1907 | Syn. | N/A | N/A | Synonym of Sphenacodon |
| Elliotsmithia | Broom | 1937 | Valid. | Middle-Upper Permian | South Africa | |
| Embolophorus | Cope | 1878 | Syn. | N/A | N/A | Synonym of Dimetrodon |
| Ennatosaurus | Efremov | 1956 | Valid. | Lower Permian | Russia | |
| Eothyris | Romer | 1937 | Valid. | Lower Permian | United States of America | |
| Eumatthevia | Broom | 1930 | Syn. | N/A | N/A | Synonym of Mycterosaurus |
| Euromycter | Reisz Maddin Fröbisch Falconnet | 2011 | Valid. | Early-Late Permian | France | |
| Glaucosaurus | Williston | 1915 | Valid. | Lower Permian | United States of America | |
| Haptodus | Gaudry | 1866 | Valid. | Late Carboniferous - Lower Permian | United States of America and Europe | |
| Heleosaurus | Broom | 1907 | Valid. | Upper Permian | South Africa | |
| Ianthasaurus | Reisz Berman | 1986 | Valid. | Late Carboniferous | United States of America | |
| Ianthodon | Kissel Reisz | 2004 | Valid. | Upper Carboniferous | United States of America | |
| Ianthosaurus | Reisz Berman | 1986 | Sic | N/A | N/A | Incorrect spelling of Ianthasaurus |
| Lupeosaurus | Romer | 1937 | Valid. | Lower Permian | United States of America | |
| Macromerion | Fritsch | 1879 | Valid. | Upper Carboniferous | Germany | |
| Mesenosaurus | Efremov | 1938 | Valid. | Lower Permian | Russia | |
| Mesonosaurus | Ivakhnenko Kurzanov | 1979 | Sic | N/A | N/A | Incorrect spelling of Mesenosaurus |
| Milosaurus | DeMar | 1970 | Valid. | Upper Carboniferous | United States of America | |
| Mycterosaurus | Williston | 1915 | Valid. | Lower Permian | United States of America | |
| Naosaurus | Cope | 1886 | Syn. | N/A | N/A | Synonym of Edaphosaurus |
| Neosaurus | Nopsca | 1923 | Valid. | Lower Permian | France | |
| Nitosaurus | Romer | 1937 | Valid. | Lower Permian | United States of America | |
| Oedaleops | Langston | 1965 | Valid. | Lower Permian | United States of America | |
| Ophiacodon | Marsh | 1878 | Valid. | Late Carboniferous-Lower Permian | United States of America and England | |
| Oromycter | Reisz | 2005 | Valid. | Lower Permian | United States of America | |
| Oxyodon | Huene | 1908 | Preocc. | N/A | N/A | Preoccupied by fish genus Oxyodon Brauer, 1906. Synonym of Sphenacodon |
| Palaeohatteria | Credner | 1888 | Valid. | Early Permian | Germany | |
| Palaeosphenodon | Baur | 1889 | Syn. | N/A | N/A | Synonym of Palaeohatteria |
| Pantelosaurus | von Huene | 1925 | Valid. | Early Permian | Germany | |
| Phreatophasma | Efremov | 1954 | Valid. | Middle Permian | Russia | |
| Poecilospondylus | Case | 1910 | Syn. | N/A | N/A | Synonym of Varanosaurus |
| Poliosaurus | Case | 1907 | Syn. | N/A | N/A | Synonym of Ophiacodon |
| Protoclepsydrops | Carroll | 1964 | Valid. | Upper Carboniferous | Canada | |
| Pyozia | Anderson Reisz | 2004 | Valid. | Middle Permian | Russia | |
| Ruthenosaurus | Reisz Maddin Fröbisch Falconnet | 2011 | Valid. | Early-Late Permian | France | |
| Ruthiromia | Eberth Brinkman | 1983 | Valid. | Lower Permian | United States of America | |
| Scoliomus | Williston Case | 1915 | Syn. | Lower Permian | United States of America | Junior synonym of Sphenacodon |
| Secodontosaurus | Romer | 1936 | Valid. | Lower Permian | United States of America | |
| Sphenacodon | Marsh | 1878 | Valid. | Late Carboniferous-Early Permian | United States of America and England | |
| Stereophallodon | Romer | 1937 | Valid. | Late Carboniferous-Early Permian | United States of America | |
| Stereorhachis | Gaudry | 1880 | Valid. | Late Carboniferous | France | |
| Theropleura | Cope | 1878 | Syn. | N/A | N/A | Synonym of Ophiacodon (in partium) and Dimetrodon (in partium) |
| Therosaurus | von Huene | 1925 | Syn. | N/A | N/A | Synonym of Ophiacodon |
| Thrausmosaurus | Fox | 1962 | Valid. | Lower Permian | United States of America | The type species, T. serratidens, was declared to be a nomen dubium |
| Trichasaurus | Williston | 1913 | Valid. | Lower Permian | United States of America | Replacement name for Trispondylus Williston, 1910 |
| Trispondylus | Williston | 1910 | Preocc. | N/A | N/A | Preoccupied by phenacodontid Trispondylus Cope, 1884 |
| Varanodon | Olson | 1965 | Valid. | Lower Permian | United States of America | |
| Varanops | Williston | 1911 | Valid. | Lower Permian | United States of America | |
| Varanosaurus | Broili | 1904 | Valid. | Lower Permian | United States of America | |
| Xyrospondylus | Reisz Heaton Pynn | 1982 | Valid. | Upper Carboniferous | United States of America | |
| Watongia | Olson | 1974 | Valid. | Middle Permian | United States of America | |
| Winfeldia | Romer | 1925 | Syn. | N/A | N/A | Synonym of Ophiacodon |
* Archaeovenator
* Casea
* Cotylorhynchus
* Ctenospondylus
* Dimetrodon
* Edaphosaurus
* Ennatosaurus
* Haptodus
* Ianthasaurus
* Mycterosaurus
* Oedaleops
* Ophiacodon
* Secodontosaurus
* Sphenacodon
* Varanodon