''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 In biological taxonomy, the type genus is the genus which defines a biological family and the root of the family name. Zoological nomenclature According to the International Code of Zoological Nomenclature, "The name-bearing type of a nomina ...

. 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 An anchovy is a small, common forage fish of the family Engraulidae. Most species are found in marine waters, but several will enter brackish water, and some in South America are restricted to fresh water. More than 140 species are placed in 1 ...

. 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 shields. If ...

(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 Pr ...

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

Taxonomy

The following species are known: * †''E. longicostatus'' (

Cope The cope (known in Latin as ''pluviale'' 'rain coat' or ''cappa'' 'cape') is a liturgical vestment, more precisely a long mantle or cloak, open in front and fastened at the breast with a band or clasp. It may be of any liturgical colours, litu ...

, 1886) -

Berriasian In the geological timescale, the Berriasian is an age/ stage of the Early/Lower Cretaceous. It is the oldest subdivision in the entire Cretaceous. It has been taken to span the time between 145.0 ± 4.0 Ma and 139.8 ± 3.0 Ma (million years a ...

Valanginian In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 139.8 ± 3.0 Ma and 132.9 ± 2.0 Ma (million years ago). The Valanginian Stage succeeds the Berriasian Stage of the Lower Cretac ...

Bahia Bahia ( , , ; meaning "bay") is one of the 26 states of Brazil, located in the Northeast Region of the country. It is the fourth-largest Brazilian state by population (after São Paulo, Minas Gerais, and Rio de Janeiro) and the 5th-largest ...

, Brazil (

Candeias Formation Candeias may refer to: Places in Brazil *Candeias, Bahia, municipality in the state of Bahia *Candeias, Minas Gerais, municipality in the state of Minas Gerais *Candeias do Jamari, municipality in the state of Rondônia People with the surname *D ...

) (=''

Diplomystus ''Diplomystus'' is an extinct genus of freshwater clupeomorph fish distantly related to modern-day extant herrings, alewives, and sardines. The genus was first named and described by Edward Drinker Cope in 1877. There are seven species of ' ...

longicostatus'' Cope, 1886) (

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen( ...

) * †''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 ag ...

Albian The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous Epoch/ Series. Its approximate time range is 113.0 ± 1.0 Ma to 100.5 ± ...

of Equatorial Guinea ( 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 Maceió (), formerly sometimes Anglicised as Maceio, is the capital and the largest city of the coastal state of Alagoas, Brazil. The name "Maceió" is an Indigenous term for a spring. Most maceiós flow to the sea, but some get trapped and form l ...

Alagoas Alagoas (, ) is one of the 27 federative units of Brazil and is situated in the eastern part of the Northeast Region. It borders: Pernambuco (N and NW); Sergipe (S); Bahia (SW); and the Atlantic Ocean (E). Its capital is the city of Maceió. ...

, 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 (geology), age or lowest stage (stratigraphy), stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by th ...

, 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