Coelogaster

{{Short description|Extinct genus of fishes}}

{{Speciesbox

| fossil_range = {{fossilrange|50|49|Early Eocene{{cite journal|last=Sepkoski |first=Jack |title=A compendium of fossil marine animal genera |journal=Bulletins of American Paleontology |volume=364 |page=560 |year=2002 |url=http://strata.ummp.lsa.umich.edu/jack/showgenera.php?taxon=611&rank=class |accessdate=2009-02-27 |url-status=dead |archiveurl=https://web.archive.org/web/20090220223520/http://strata.ummp.lsa.umich.edu/jack/showgenera.php?taxon=611&rank=class |archivedate=2009-02-20 }}}}

| image = Coelogaster leptostea 7.jpg

| image_caption = Fossil specimen

| taxon = Coelogaster leptostea

| parent_authority = Eastman, 1905

| authority = (Eastman, 1905)

| synonyms = * †Chanoides leptostea Eastman, 1905

• †Coelogaster analis Eastman, 1905 ex Agassiz, 1835
• †Eucoelogaster White & Moy-Thomas, 1940

}}

Coelogaster is an extinct genus of marine ray-finned fish that lived during the early Eocene. It contains a single species, C. leptostea, known from the famous Monte Bolca site of Italy.{{cite journal|last=Sepkoski |first=Jack |title=A compendium of fossil marine animal genera |journal=Bulletins of American Paleontology |volume=364 |page=560 |year=2002 |url=http://strata.ummp.lsa.umich.edu/jack/showgenera.php?taxon=611&rank=class |accessdate=2009-02-27 |url-status=dead |archiveurl=https://web.archive.org/web/20090220223520/http://strata.ummp.lsa.umich.edu/jack/showgenera.php?taxon=611&rank=class |archivedate=2009-02-20 }}{{Cite web |title=PBDB Taxon |url=https://paleobiodb.org/classic/basicTaxonInfo?taxon_no=441598 |access-date=2024-05-25 |website=paleobiodb.org}}

It is classified in the Anotophysi, and is generally considered a chanid of uncertain affinities, making it related to modern milkfish.{{Citation |last=Taverne |first=Emmanuel Fara, Mireille Gayet, Louis |title=The Fossil Record of Gonorynchiformes |date=2010 |work=Gonorynchiformes and Ostariophysan Relationships |pages=173-226 |url=https://hal.science/hal-00441945/document |access-date=2024-05-09 |publisher=CRC Press |doi=10.1201/b10194-6 |isbn=978-0-429-06156-1}}{{Cite journal |last1=Carnevale |first1=G. |last2=Bannikov |first2=Alexandre F. |last3=Marramà |first3=G. |last4=Tyler |first4=James C. |last5=Zorzin. |first5=R. |date=2014 |title=The Bolca Fossil-Lagerstätte: A window into the Eocene World. 5. The Pesciara- Monte Postale Fossil-Lagerstätte: 2. Fishes and other vertebrates. Excursion guide |url=https://iris.unito.it/bitstream/2318/149338/1/Carnevale%20et%20al%202014%20The%20Pesciara%20F-L.%20Fishes%20and%20other%20vertebrates2.pdf |journal=Rendiconti della Società Paleontologica Italiana |volume=4 |issue=1 |pages=i–xxvii |hdl=10088/25678}}{{Cite journal |last=Patterson |first=Colin |date=1984 |title=Chanoides , a marine Eocene otophysan fish (Teleostei: Ostariophysi) |url=http://www.tandfonline.com/doi/abs/10.1080/02724634.1984.10012021 |journal=Journal of Vertebrate Paleontology |language=en |volume=4 |issue=3 |pages=430–456 |doi=10.1080/02724634.1984.10012021 |issn=0272-4634}}{{Cite journal |last1=Murray |first1=Alison M. |last2=Brinkman |first2=Donald B. |last3=Friedman |first3=Matt |last4=Krause |first4=David W. |date=2023-10-17 |title=A large, freshwater chanid fish (Ostariophysi: Gonorynchiformes) from the Upper Cretaceous of Madagascar |url=http://dx.doi.org/10.1080/02724634.2023.2255630 |journal=Journal of Vertebrate Paleontology |volume=43 |issue=2 |doi=10.1080/02724634.2023.2255630 |issn=0272-4634}}

It was initially named without formal description by Louis Agassiz in 1835 as Clupea leptostea, alongside another fish known as Coelogaster analis. In 1905, Eastman officially described C. analis based on Agassiz's original name, and also described Clupea leptostea under the new genus Chanoides. A later revision found both these taxa to be synonymous, leading to the new combination Coelogaster leptostea.{{Cite journal |last1=Marramà |first1=Giuseppe |last2=Carnevale |first2=Giorgio |date=2014 |title=Eocene round herring (Teleostei: Clupeidae) from Monte Bolca, Italy |url=https://doi.org/10.4202/app.00057.2014 |journal=Acta Palaeontologica Polonica |language=en |doi=10.4202/app.00057.2014 |issn=0567-7920|hdl=2318/1525495 |hdl-access=free }}

White & Moy-Thomas (1940) suggested the genus name Eucoelogaster as a replacement, as the previous genus name Coelogaster was already preoccupied by a weevil genus, but most authorities have since kept Coelogaster as the genus name, with the weevil genus instead going by Dietzella.