''Ellimmichthys'' is an extinct genus of freshwater

clupeomorph Otocephala is a clade of ray-finned fishes within the infraclass Teleostei that evolved some 230 million years ago. It is named for the presence of a hearing (otophysic) link from the swimbladder to the inner ear. Other names proposed for the g ...

fish belonging to the order Ellimmichthyiformes, of which it is the type genus. It was a distant relative of modern

herrings Herring are forage fish, mostly belonging to the family of Clupeidae. Herring often move in large schools around fishing banks and near the coast, found particularly in shallow, temperate waters of the North Pacific and North Atlantic Oceans ...

and anchovies. It inhabited freshwater rift lakes in the supercontinent of

West Gondwana A craton is an ancient part of the Earth's continental crust which has been more or less stable since Precambrian times. Cratons whose ancient rocks are widely exposed at the surface, often with relatively subdued relief, are known as Shield (geol ...

(comprising modern South America and Africa) during the

Early Cretaceous The Early Cretaceous ( geochronological name) or the Lower Cretaceous (chronostratigraphic name), is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 145 Ma to 100.5 Ma. Geology Pro ...

, and fossil remains are known from formations in both South America (Brazil) and Africa (

Equatorial Guinea Equatorial Guinea ( es, Guinea Ecuatorial; french: Guinée équatoriale; pt, Guiné Equatorial), officially the Republic of Equatorial Guinea ( es, link=no, República de Guinea Ecuatorial, french: link=no, République de Guinée équatoria ...

Taxonomy

The following species are known: * †''E. longicostatus'' ( Cope, 1886) - Berriasian/ Valanginian of Bahia, Brazil ( Candeias Formation) (='' Diplomystus longicostatus'' Cope, 1886) ( type species) * †''E. goodi'' (

Eastman Eastman may refer to: People * Eastman (surname) * Eastman Nixon Jacobs (1902–1987), American aerodynamicist * John Eastman (b 1960), American lawyer and founding director of the Center for Constitutional Jurisprudence * Jonathan Eastman Johnso ...

, 1912) -

Aptian The Aptian is an age in the geologic timescale or a stage in the stratigraphic column. It is a subdivision of the Early or Lower Cretaceous Epoch or Series and encompasses the time from 121.4 ± 1.0 Ma to 113.0 ± 1.0 Ma (million years ago), a ...

/ Albian of

( Cocobeach Formation) (=''Diplomystus goodi'' Eastman, 1912, ''D. elberti'' Weiler, 1922, '' Ellimma guineensis'' Gayet, 1989) * †''E. spinosus'' de Figuereido & Gallo, 2021 - Berriasian/Valanginian of Bahia, Brazil (Candeias Formation) Another species ''E. maceioensis'' Malabarba ''et al'', 2004 from the Aptian-aged Maceió Formation of Alagoas, Brazil likely does not belong to this genus as it does not display diagnostic morphological characteristics. However, the genus as a whole may also be

paraphyletic In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...

with respect to '' Ellimma''. The

sister genus In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and t ...

to ''Ellimmichthys'' is thought to be '' Eoellimmichthys'', a marine paraclupeid that lived much later during the

Early Eocene In the geologic timescale the Ypresian is the oldest age or lowest stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by the Eocene Lutetian Age. The Ypresian i ...

, with fossils known from

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 ...

, Italy. ''Eoellimmichthys'' is thought to have been the last surviving paraclupeid, and the last surviving marine ellimmichthyiform as a whole.

References

Clupeiformes Prehistoric ray-finned fish genera Early Cretaceous bony fish Early Cretaceous fish of South America Early Cretaceous fish of Africa Berriasian genus first appearances Valanginian genera Aptian genera Albian genus extinctions Fossils of Brazil Fossils of Equatorial Guinea Taxa named by David Starr Jordan Fossil taxa described in 1919 {{Paleo-rayfinned-fish-stub