''Eoeugnathus'' (Greek for "dawn true-jaw") is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of prehistoric 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 ...

belonging to the

Halecomorphi Halecomorphi is a taxon of Actinopterygii, ray-finned bony fish in the clade Neopterygii. The only extant Halecomorph species are the bowfin (''Amia calva'') and eyespot bowfin (''Amia ocellicauda''), but the group contains many extinct species i ...

.The Paleobiology Database ''Eoeugnathus'' entry
/ref> ''Eoeugnathus'' existed during the

Middle Triassic In the geologic timescale, the Middle Triassic is the second of three epoch (geology), epochs of the Triassic period (geology), period or the middle of three series (stratigraphy), series in which the Triassic system (stratigraphy), system is di ...

in what is now Europe. It contains two species: * ''E. bellottii'' ( Rueppel, 1857) -

Ladinian The Ladinian is a stage and age in the Middle Triassic series or epoch. It spans the time between Ma and ~237 Ma (million years ago). The Ladinian was preceded by the Anisian and succeeded by the Carnian (part of the Upper or Late Triassic ...

of Italy and Switzerland ( Meride Formation, Perledo-Varenna Formation) (='' Allolepidotus bellottii'' Rueppel, 1857) * ''E. megalepis'' Brough, 1939 (

type species In International_Code_of_Zoological_Nomenclature, 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 spe ...

) - latest

Anisian In the geologic timescale, the Anisian is the lower stage (stratigraphy), stage or earliest geologic age, age of the Middle Triassic series (stratigraphy), series or geologic epoch, epoch and lasted from million years ago until million years ag ...

to late

of Italy (

Besano Formation The Besano Formation is a geological formation in the southern Alps of northwestern Italy and southern Switzerland. This formation, a thin but fossiliferous succession of Dolomite (rock), dolomite and Shale, black shale, is famous for its preserva ...

), Switzerland ( Prosanto Formation), and Spain (

Muschelkalk The Muschelkalk (German for "shell-bearing limestone"; ) is a sequence of sedimentary rock, sedimentary rock strata (a lithostratigraphy, lithostratigraphic unit) in the geology of central and western Europe. It has a Middle Triassic (240 to 230 m ...

) It was initially placed in the

Caturidae Caturidae is an extinct Family (biology), family of predatory Amiiformes, amiiform Actinopterygii, ray-finned fish, being the sister-group to the extant family Amiidae. Though their body form is very different than the modern bowfin, a number of f ...

and then the Panxianichthyiformes, but more recent studies have placed it in the new ionoscopiform family Subortichthyidae.

References

Halecomorphi Triassic bony fish Prehistoric ray-finned fish genera Triassic fish of Europe Middle Triassic fish Anisian genus first appearances Ladinian genus extinctions Fossils of Italy Fossils of Switzerland Fossils of Spain Fossil taxa described in 1939 {{Triassic-fish-stub

See also

References