''Hulettia'' is an extinct genus of

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of sk ...

known from

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

. This fish

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

contains two species, ''H. americana'' and ''H. hawesi''.

Species

The type species, ''H. americana'' is originally described as a species of ''

Pholidophorus ''Pholidophorus'' (from , 'horny scale' and , 'to bear') is an extinct genus of Stem group, stem-teleost fish. Numerous species were assigned to this genus in the past, but only the type species ''Pholidophorus latiusculus'', from the Late Tria ...

'' in 1899. In 1984, its own genus name ''Hulettia'' is given, after

Hulett, Wyoming Hulett is a town in Crook County, Wyoming, United States. The population was 309 at the 2020 census. Geography Devils Tower, the first proclaimed United States national monument, is away. According to the United States Census Bureau, the to ...

. Holotype is known from

Sundance Formation The Sundance Formation is a western North American sequence of Middle Jurassic to Upper Jurassic age Dating from the Bathonian to the Oxfordian, around 168-157 Ma, It is up to 100 metres thick and consists of marine shale, sandy shale, sandstone ...

South Dakota South Dakota (; Sioux language, Sioux: , ) is a U.S. state, state in the West North Central states, North Central region of the United States. It is also part of the Great Plains. South Dakota is named after the Dakota people, Dakota Sioux ...

, while other specimens are also known from Wanakah (Summerville) Formation,

Todilto Formation The Todilto Formation is a geologic formation in northern New Mexico and southeastern Colorado. It preserves fossils dating back to the Callovian stage of the middle Jurassic period. Description The formation consists of evaporites. It is divi ...

and Ralston Creek Formation. Second species, ''H. hawesi'' is described from

Morrison Formation The Morrison Formation is a distinctive sequence of Upper Jurassic sedimentary rock found in the western United States which has been the most fertile source of dinosaur fossils in North America. It is composed of mudstone, sandstone, siltston ...

of Colorado. This species is named after William Hawes who found the holotype. ''H. americana'' reached their maximum standard length (excluding fins) of , while ''H. hawesi'' is much smaller, with standard length of (about total length).

Classification

At 1984, it was classified as Halecostomi ''

incertae sedis or is a term used for a taxonomy (biology), taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty ...

''. Later study shows that is likely a member of

Neopterygii Neopterygii (from Greek νέος ''neos'' 'new' and πτέρυξ ''pteryx'' 'fin') is a subclass of ray-finned fish (Actinopterygii). Neopterygii includes the Holostei and the Teleostei, of which the latter comprise the vast majority of extant ...

, pan-

holostean Holostei is a group of ray-finned bony fish. It is divided into two major clades, the Halecomorphi, represented by the single living genus, '' Amia'' with two species, the bowfins (''Amia calva'' and ''Amia ocellicauda''), as well as the Ginglymo ...

Paleoecology

Formations that ''H. americana'' known are considered as marine environment, while Morrison Formation where ''H. hawesi'' described shows freshwater environment. Discovered specimens show evidence of predation upon the smaller species of fish ''

Todiltia ''Todiltia'' is an extinct genus of prehistoric bony fish. See also * Prehistoric fish * List of prehistoric bony fish This list of prehistoric bony fish is an attempt to create a comprehensive listing of all Genus, genera from the fossil re ...

''.http://nmnaturalhistory.org/hulettia.html New Mexico Museum of Natural History, 1999

References

External links

Bony fish in the online Sepkoski Database
{{Taxonbar, from=Q5935653 Prehistoric neopterygii Morrison fauna