''Tomistoma'' is a genus of gavialid crocodilians. They are noted for their long narrow snouts used to catch fish, similar to the

gharial The gharial (''Gavialis gangeticus''), also known as gavial or fish-eating crocodile, is a crocodilian in the family Gavialidae and among the longest of all living crocodilians. Mature females are long, and males . Adult males have a distinct b ...

. ''Tomistoma'' contains one

extant Extant is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Extant taxon, a taxon which is not extinct, ...

(living) member, the

false gharial The false gharial (''Tomistoma schlegelii''), also known by the names Malayan gharial, Sunda gharial and tomistoma is a freshwater crocodilian of the family Gavialidae native to Peninsular Malaysia, Borneo, Sumatra and Java. It is listed as Vu ...

(''Tomistoma schlegelii''), as well as potentially several extinct species: ''T. cairense'', ''T. lusitanicum'', ''T. taiwanicus'', ''T. coppensi'', and ''T. dowsoni''. However, these species may need to be reclassified to different genera as studies have shown them to be

paraphyletic In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...

. Unlike the

, the false gharial's snout broadens considerably towards the base and so is more similar to those of true crocodiles than the gharial, whose

osteology Osteology () is the scientific study of bones, practised by osteologists. A subdiscipline of anatomy, anthropology, and paleontology, osteology is the detailed study of the structure of bones, skeletal elements, teeth, microbone morphology, funct ...

indicated a distinct lineage from all other living crocodilians.Piras, P., Colangelo, P., Adams, D. C., Buscalioni, A., Cubo, J., Kotsakis, T., & Raia, P. (2010). ''The Gavialis–Tomistoma debate: the contribution of skull ontogenetic allometry and growth trajectories to the study of crocodylian relationships''. Evolution & development, 12(6): 568−579. However, although more morphologically similar to

Crocodylidae Crocodiles (family Crocodylidae) or true crocodiles are large semiaquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. The term crocodile is sometimes used even more loosely to include all extant mem ...

based on skeletal features, recent molecular studies using

DNA sequencing DNA sequencing is the process of determining the nucleic acid sequence – the order of nucleotides in DNA. It includes any method or technology that is used to determine the order of the four bases: adenine, guanine, cytosine, and thymine. Th ...

consistently indicate that the false gharial and by inference other related extinct forms traditionally viewed as belonging to the crocodylian subfamily Tomistominae actually belong to Gavialoidea and Gavialidae. Gavialidae - Tomistoma calaritanus

Fossils of extinct ''Tomistoma'' species have been found in deposits of

Paleogene The Paleogene ( ; British English, also spelled Palaeogene or Palæogene; informally Lower Tertiary or Early Tertiary) is a geologic period, geologic period and system that spans 43 million years from the end of the Cretaceous Period million yea ...

Neogene The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period Mya. ...

, and

Quaternary The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS). It follows the Neogene Period and spans from 2.58 million years ...

ages in Taiwan, Uganda, Italy, Portugal, Egypt and India, but nearly all of them are likely to be distinct genera due to older age compared to the false gharial. The below cladogram of the major living crocodile groups is based on molecular studies and shows the false gharial's close relationships: Here is a more detailed cladogram from a 2018 tip dating study by Lee & Yates simultaneously using morphological, molecular (

), and stratigraphic ( fossil age) data that shows the false gharial's proposed placement within Gavialidae, including

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

members:

References

{{Taxonbar, from=Q2077433, from2=Q242464, from3=Q30593586, from4=Q41168422, from5=Q85883732, from6=Q108885176, from7=Q41168428 Gavialidae Reptile genera Reptile genera with one living species Taxa named by Salomon Müller