''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 Monte Bolca is a lagerstätte near Verona, Italy that was one of the first fossil sites with high quality preservation known to Europeans, and is still an important source of fossils from the Eocene. Geology Monte Bolca was uplifted from the T ...

site of Italy. It is classified in the Anotophysi, and is generally considered a chanid of uncertain affinities, making it related to modern milkfish. 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''. 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''.

References

Chanidae Prehistoric ray-finned fish genera Eocene fish of Europe Ypresian genera Fossils of Italy Fossil taxa described in 1905 {{paleo-rayfinned-fish-stub