''Coelogaster'' is an extinct genus of marine

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 ...

that lived during the early

Eocene The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ...

. It contains a single species, ''C. leptostea'', known from the famous

Monte Bolca Monte Bolca is an Ypresian, Early Eocene-aged geologic site located near Verona, Italy, Verona, Italy. A ''Konservat-Lagerstätte'', it contains an extremely well-preserved and diverse marine biota, including the most diverse fish fauna of any Ce ...

site of Italy. It is classified in the

Anotophysi Ostariophysi is the second-largest superorder of fish. Members of this superorder are called ostariophysians. This diverse group contains 10,758 species, about 28% of known fish species in the world and 68% of freshwater species, and are present ...

, and is generally considered a chanid of uncertain affinities, making it related to modern

milkfish The milkfish (''Chanos chanos'') is a widespread species of ray-finned fish found throughout the Indo-Pacific. It is the sole living species in the family Chanidae, and the only living member of the genus ''Chanos''. The repeating scientific na ...

. It was initially named without formal description by Louis Agassiz in 1835 as ''

Clupea ''Clupea'' is genus of planktivorous bony fish belonging to the family Clupeidae, commonly known as herrings. They are found in the shallow, temperate waters of the North Pacific and the North Atlantic oceans, including the Baltic Sea. Two main ...

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 Weevils are beetles belonging to the superfamily Curculionoidea, known for their elongated snouts. They are usually small – less than in length – and herbivorous. Approximately 97,000 species of weevils are known. They belong to several fa ...

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