# Redfieldius > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Redfieldius > Markdown URL: https://mediated.wiki/source/Redfieldius.md > Source: https://en.wikipedia.org/wiki/Redfieldius > Source revision: 1296752438 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) {{Short description|Extinct genus of fishes}} {{Speciesbox | fossil_range = [Early Jurassic](/source/Early_Jurassic), {{fossil range|Hettangian|Sinemurian|[Hettangian](/source/Hettangian)-[Sinemurian](/source/Sinemurian)}} | image = Redfieldius gracilis.jpg | image_caption = Fossil specimen at the [UMMNH](/source/UMMNH) | taxon = Redfieldius gracilis | authority = ([Redfield](/source/John_Howard_Redfield), 1837) | parent_authority = [Hay](/source/Oliver_Perry_Hay), 1899 | synonyms = * †''Catopterus'' Redfield, 1837 }} '''''Redfieldius''''' is an [extinct](/source/Extinction) [genus](/source/genus) of freshwater [ray-finned fish](/source/Actinopterygii) that inhabited eastern North America during the [Early Jurassic](/source/Early_Jurassic) period. It contains a single species, '''''R. gracilis''''', known from the [Hettangian](/source/Hettangian) to the [Sinemurian](/source/Sinemurian) of the northeastern United States. It is the [type genus](/source/type_genus) and was the last surviving member of the order [Redfieldiiformes](/source/Redfieldiiformes), which was widespread and diverse throughout the preceding [Triassic](/source/Triassic) period.{{Cite web |title=PBDB Taxon |url=https://paleobiodb.org/classic/basicTaxonInfo?taxon_no=275586 |access-date=2024-09-08 |website=paleobiodb.org}}{{Cite journal |last1=Schaeffer |first1=Bobb |last2=McDonald |first2=Nicholas G. |date=1978 |title=Redfieldiid fishes from the Triassic-Liassic Newark Supergroup of eastern North America. Bulletin of the AMNH; v. 159, article 4 |url=https://digitallibrary.amnh.org/items/52d8aa67-6a45-4f02-b887-e7e3094c401d |journal=Bulletin of the American Museum of Natural History |volume=159 |issue=4 |pages=131–173}} It is notable for representing possibly the first fossil [bony fish](/source/Osteichthyes) collected from North America, with a specimen from [Middletown](/source/Middletown%2C_Connecticut) collected in 1816 by [Benjamin Silliman](/source/Benjamin_Silliman).{{Cite journal |last=Brignon |first=Arnaud |date=2017-02-01 |title=The earliest discoveries of articulated fossil fishes (Actinopterygii) in the United States: A historical perspective |url=https://ajsonline.org/article/65717-the-earliest-discoveries-of-articulated-fossil-fishes-actinopterygii-in-the-united-states-a-historical-perspective |journal=American Journal of Science |language=en |volume=317 |issue=2 |pages=216–250 |doi=10.2475/02.2017.03|url-access=subscription }} == Taxonomy == thumb|left|Fossil specimen It was initially described in the genus ''Catopterus'' by naturalist [John Howard Redfield](/source/John_Howard_Redfield), but later taxonomic revisions found ''Catopterus'' to already be a synonym for the early lungfish ''[Dipterus](/source/Dipterus)''. Due to this, [Oliver Perry Hay](/source/Oliver_Perry_Hay) reclassified it into the new genus ''Redfieldius'', named in honor of Redfield. Previously, many other species were classified into ''Catopterus''/''Redfieldius'', but most of these have either been synonymized with ''R. gracilis'' or (in the case of former Triassic species classified into this genus) moved into their own genera.{{Cite book |last=Woodward |first=Arthur Smith |url=https://books.google.com/books?id=ssngSQEhXd4C |title=Catalogue of the Fossil Fishes in the British Museum (Natural History) |date=1895 |publisher=Taylor & Francis |language=en}} == Distribution == ''Redfieldius'' appears to have been widespread in the [rift lake](/source/rift_lake)s of the upper [Newark Supergroup](/source/Newark_Supergroup), with fossils known from [Connecticut](/source/Connecticut) ([East Berlin](/source/East_Berlin_Formation), [Portland](/source/Portland_Formation) & [Shuttle Meadow Formation](/source/Shuttle_Meadow_Formation)s), [New Jersey](/source/New_Jersey) ([Boonton Formation](/source/Boonton_Formation)), and [Virginia](/source/Virginia) ([Midland Formation](/source/Midland_Formation)). There have also been reports from [Massachusetts](/source/Massachusetts), but no specimens have been identified. == Description == thumb|''Life restoration'' ''Redfieldius'' was of medium size, and usually did not exceed 20 centimeters in length. The body was slightly robust, oval in shape; the snout was rounded, the eyes large and the mouth was equipped with small teeth. Like all its close relatives, ''Redfieldius'' also had a single triangular dorsal fin set far back, practically mirroring the anal fin, which was very similar in shape and size. The ventral fins were small, while the pectoral fins were slightly larger. The [caudal fin](/source/caudal_fin) was slightly [heterocercal](/source/heterocercal), while there was a single [branchiostegal](/source/Glossary_of_ichthyology) reduced to a plate-shaped bone. All the fins were equipped with extremely thin fulcrums. The scales were rhomboid, and those in the anterior part of the body were larger, arranged in diagonal rows. The external nasal opening was enclosed by a premaxillary bone, a nasal, a rostral and an adnasal bone. ''Redfieldius'', unlike other closely related fish, had a skull heavily ornamented with tubercles, particularly the area around the orbit and the tip of the snout.{{Cite journal |last=Schaeffer |first=Bobb |date=1984 |title=On the relationships of the Triassic-Liassic redfieldiiform fishes |url=https://digitallibrary.amnh.org/items/5a3cbf95-9ce5-44db-93d9-43735fcb3e59 |journal=American Museum Novitates |issue=2795 }} == References == {{Neopterygii}}{{Taxonbar|from=Q91932110}} Category:Monotypic prehistoric ray-finned fish genera Category:Redfieldiiformes Category:Jurassic bony fish Category:Jurassic fish of North America Category:Hettangian genus first appearances Category:Sinemurian genus extinctions Category:Fossils of the United States Category:Fossils of New Jersey Category:Taxa named by Oliver Perry Hay Category:Fossil taxa described in 1899 --- Adapted from the Wikipedia article [Redfieldius](https://en.wikipedia.org/wiki/Redfieldius) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Redfieldius?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.