Ceratodontidae Temporal range: | |
---|---|
Ceratodus | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Sarcopterygii |
Class: | Dipnoi |
Order: | Ceratodontiformes |
Family: | † Ceratodontidae Gill, 1872 |
Genera | |
See text |
Ceratodontidae is an extinct family of lungfish with fossils known worldwide from the earliest Triassic to the Eocene.
Although the extant Queensland lungfish was formerly also classified in this family due to its similar appearance, phylogenetic and morphological evidence indicates that it belongs in a different family, Neoceratodontidae. A morphological study by Kemp et al (2017) proposed that Ceratodontidae was more closely related to modern African (Protopteridae) and South American lungfish (Leptosirenidae) than Queensland lungfish. [1] However, Brownstein, Harrington & Near (2023) found Ceratodontidae to lie outside the crown group of modern lungfish, with all modern lungfish more closely related to each other than to Ceratodontidae. [2]
The following genera are known from the family: [3]
Paraceratodus was also classified in this family but phylogenetic evidence supports it being the most basal member of Ceratodontoidei. [1] [4]
Lungfish are freshwater vertebrates belonging to the class Dipnoi. Lungfish are best known for retaining ancestral characteristics within the Osteichthyes, including the ability to breathe air, and ancestral structures within Sarcopterygii, including the presence of lobed fins with a well-developed internal skeleton. Lungfish represent the closest living relatives of the tetrapods. The mouths of lungfish typically bear tooth plates, which are used to crush hard shelled organisms.
A living fossil is an extant taxon that phenotypically resembles related species known only from the fossil record. To be considered a living fossil, the fossil species must be old relative to the time of origin of the extant clade. Living fossils commonly are of species-poor lineages, but they need not be. While the body plan of a living fossil remains superficially similar, it is never the same species as the remote relatives it resembles, because genetic drift would inevitably change its chromosomal structure.
Lagenorhynchus is a genus of oceanic dolphins in the infraorder Cetacea, presently containing six extant species. However, there is consistent molecular evidence that the genus is polyphyletic and several of the species are likely to be moved to other genera. In addition, the extinct species Lagenorhynchus harmatuki is also classified in this genus.
The South American lungfish, also known as the American mud-fish and scaly salamanderfish, is the single species of lungfish found in swamps and slow-moving waters of the Amazon, Paraguay, and lower Paraná River basins in South America. Notable as an obligate air-breather, it is the sole member of its family Lepidosirenidae, although some authors also place Protopterus in the family. In Brazil, it is known by the indigenous language Tupi name piramboia, which means "snake-fish", and synonyms pirarucu-bóia, traíra-bóia, and caramuru.
Neoceratodus is a genus of lungfish in the family Neoceratodontidae. The extant Australian lungfish is the only surviving member of this genus, but it was formerly much more widespread, being distributed throughout Africa, Australia, and South America. Species were also much more diverse in body plan; for example, the Cretaceous species Neoceratodus africanus was a gigantic species that coexisted with Spinosaurus in what is now the Kem Kem Formation of Morocco. The earliest fossils from this genus are of Neoceratodus potkooroki from the mid Cretaceous (Albian-Cenomanian) Griman Creek Formation of Australia; remains from the Late Jurassic of Uruguay assigned to this genus probably do not belong to the genus.
Protopterus is the genus of four species of lungfish found in Africa. Protopterus is considered the sole genus in the family Protopteridae, which is grouped with Lepidosiren in the order Lepidosireniformes.
Tomistoma is a genus of gavialid crocodilians. They are noted for their long narrow snouts used to catch fish, similar to the gharial. Tomistoma contains one extant (living) member, the false gharial, as well as potentially several extinct species: T. cairense, T. lusitanicum and T. coppensi. Previously assigned extinct species known from fossils are reclassified as different genera such as Eogavialis, Toyotamaphimeia and Sutekhsuchus.
The Gnathorhizidae are an extinct family of lungfish that lived from the late Carboniferous until the middle Triassic. Gnathorhizid fossils have been found in North America, Madagascar, Australia, and possibly Eastern Europe and South Africa. They are characterized by high-ridged toothplates that form cutting blades and a reduction in cranial bones.
Euryzygomatomys is a genus of South American rodents, commonly called guiaras, in the family Echimyidae. It contains two extant and one fossil species, found in Argentina, Brazil and Paraguay. They are as follows:
Diploglossidae is a family of anguimorph lizards native to the Americas, with most genera being endemic to Hispaniola. Most members of this family are known as galliwasps. They were formerly considered a subfamily of Anguidae, but genetic evidence has shown them to be less closely related to other members of Anguidae than Anniellidae is.
Ferganoceratodus is a genus of prehistoric lungfish known from the Mesozoic of Asia and Africa. Based on morphological evidence, it has either been recovered as a basal member of the Ceratodontiformes or to be the sister group of the Neoceratodontidae.
Gnathorhiza is an extinct genus of prehistoric lobe-finned fish (lungfish) which lived from the Carboniferous period to the Early Triassic epoch. It is the only known lungfish genus to have crossed the Permo-Triassic boundary. Several species have been described, ranging in size from 5 to 50 centimeters.
Mioceratodus is an extinct genus of lungfish in the family Neoceratodontidae, which also contains the extant Queensland lungfish. It is known only from Oligocene and Miocene-aged sediments in Australia, although phylogenetic evidence supports it having first diverged from its closest relative, Neoceratodus, during the Late Jurassic or Early Cretaceous period.
Metaceratodus is an extinct genus of prehistoric lungfish in the family Ceratodontidae, with an indeterminate specimen known from the Late Triassic (Norian)-aged Lissauer Breccia of Poland and more complete specimens known from the Late Cretaceous of Queensland, Australia and Argentina. The genus was named and described by Frederick Chapman in 1914.
Paraceratodus is an extinct genus of prehistoric lungfish. Only one species, P. germaini, is known from the latest Permian or earliest Triassic period of Madagascar. Phylogenetic evidence supports it being the most basal member of the suborder Ceratodontoidei, which contains modern lungfish, and as with the rest of the order it likely diverged during the late Carboniferous.
The Scalopinae, or New World moles, are one of three subfamilies of the family Talpidae, which consists of moles and mole-like animals; the other two subfamilies being the Old World talpids and the Chinese shrew-like moles (Uropsilinae). The Scalopinae are the only Talpidae subfamily to consist entirely of undisputed moles and no mole-like close relatives such as shrew-moles or desmans.
Neoceratodontidae is a family of lungfish containing Neoceratodus and the extinct Mioceratodus. It, Lepidosirenidae, and Protopteridae represent the only lungfish families still extant.
The Amerophidia, also known as amerophidian snakes, are a clade of snakes that contains two families: Aniliidae and the boa-like Tropidophiidae.
Ceratodontiformes is the only extant order of lungfish, containing the families Neoceratodontidae, Lepidosirenidae, and Protopteridae as well as many other extinct groups. Members of this group are the only lungfish known to have survived the Permian-Triassic extinction event. Although lungfish originated in marine environments, the Ceratodontiformes have been an exclusively freshwater group since the Carboniferous. This order was formerly considered the suborder Ceratodontoidei.
Anne Kemp is an Australian ichthyologist and paleoichthyologist who specializes in lungfishes. Her primary area of study is the Australian lungfish. She has served as a research fellow at Griffith University since 2010. Prior to this, she had also served as a research fellow at Queensland Museum between 1980 and 1991, and at the Centre of Microscopy at the University of Queensland between 1999 and 2008.