Enchodontoidei
   HOME

TheInfoList



OR:

The Enchodontoidei are 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 ...
superorder Order () is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized ...
of aulopiform fish known from the
Early Cretaceous The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 ...
to the
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 ...
. They were among the dominant predatory marine fish groups in the Late Cretaceous, achieving a worldwide distribution. They were an extremely diverse group, with some developing fusiform body plans whereas others evolved elongated body plans with long beaks, superficially similar to eels and needlefish. They could also grow to very large sizes, as seen with '' Cimolichthys'' and '' Stratodus'', the latter of which is the largest aulopiform known. Their most famous member is the widespread, abundant, and long-lasting genus ''
Enchodus ''Enchodus'' (from , 'spear' and 'tooth') is an extinct genus of aulopiformes, aulopiform Actinopterygii, ray-finned fish related to alepisaurus, lancetfish and lizardfish. Species of ''Enchodus'' flourished during the Late Cretaceous, where t ...
''. Most enchodontoids went extinct at the end of the Cretaceous, although some dercetids survived into the
Early Paleocene The Danian is the oldest age (geology), age or lowest stage (stratigraphy), stage of the Paleocene Epoch or series (stratigraphy), Series, of the Paleogene Period or system (stratigraphy), System, and of the Cenozoic Era or Erathem. The beginnin ...
and ''Stratodus'' into 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 ...
of the
Trans-Saharan seaway The Trans-Saharan seaway was a sea in the present-day Sahara in the Late Cretaceous period to the Early Eocene In the geologic timescale the Ypresian is the oldest age (geology), age or lowest stage (stratigraphy), stratigraphic stage of the Eoce ...
. Some remains of ''Enchodus'' have also been recovered from the
Paleocene The Paleocene ( ), or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), ...
and
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 ...
, although this may just represent reworked material.


Taxonomy

Although initially classified among
Stomiiformes Stomiiformes is an order (biology), order of deep-sea ray-finned fishes of very diverse Morphology (biology), morphology. It includes, for example, Barbeled dragonfish, dragonfishes, lightfishes (Gonostomatidae and Phosichthyidae), loosejaws, ma ...
and then the
Salmoniformes Salmoniformes (, lit. "salmon-shaped") is an Order (biology), order of Actinopterygii, ray-finned fishes native to the temperate and subarctic Northern Hemisphere. It contains two suborders: Salmonoidei (containing only the Salmonidae) and Esocoi ...
in the mid-20th century, studies since the 1970s have found them to be deeply nested among the lizardfishes and lancetfishes in the order
Aulopiformes Aulopiformes is a diverse order (biology), order of Marine (ocean), marine ray-finned fish consisting of some 15 Extant taxon, extant and several prehistoric family (biology), families with about 45 genera and over 230 species. The common names ...
. Some studies group them with the extant superorder Alepisauroidei, although a majority consider them their own distinct group. Their taxonomy is disputed, with some studies finding the group to be
polyphyletic A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as Homoplasy, homoplasies ...
with its members scattered among the Aulopiformes, although most recent studies have recovered the group as monophyletic, based on the synapomorphy of
maxilla In vertebrates, the maxilla (: maxillae ) is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxil ...
included in the gape of the mouth. Other studies have classified the different superfamilies as their own individual suborders, though most now classify them as one suborder. The taxonomy within the group is even more disputed, with multiple families within the group recovered as
paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...
in some studies.


Classification

The following taxonomy is partially based on Silva & Gallo (2011). Other studies have found differing classifications for the group. * Suborder †Enchodontoidei ** Genus †'' Atolvorator'' ** Genus †'' Hemisaurida'' (possibly in the Halecidae) ** Genus †'' Spinascutichthys'' ** Genus †'' Stratodus'' (possibly in the Dercetidae) ** Genus †'' Rharbichthys'' (possibly in the Enchodontidae) ** Genus †'' Yabrudichthys'' ** Family † Nardorexidae ** Family † Aspidopleuridae (containing only '' Aspidopleurus'') ** Family ? † Serrilepidae (alternatively within the Halecidae) ** Superfamily †Ichthyotringoidea *** Genus †'' Ursichthys'' *** Family † Ichthyotringidae *** Family † Apateopholidae ** Superfamily †Cimolichthyoidea *** Family † Cimolichthyidae *** Family † Dercetidae *** Family †
Prionolepididae ''Prionolepis'' is a genus of prehistoric ray-finned fish belonging to the order Alepisauriformes. Fossil record These ray-finned fish lived in the Upper Cretaceous (Cenomanian - Turonian, about 95-90 million years ago). Fossils have been found ...
** Superfamily †Enchodontoidea *** Family † Enchodontidae ** Superfamily †Halecoidea *** Family †
Halecidae Halecidae is an extinct family of aulopiform ray-finned fish known from the Cretaceous Period. It is one of the Enchodontoidei, a diverse group of aulopiforms that were dominant marine fish during the Cretaceous Period. It contains the followi ...


References


Sources

*


Further reading

* * * * {{Taxonbar, from=Q25939397
A dagger, obelisk, or obelus is a typographical mark that usually indicates a footnote if an asterisk has already been used. The symbol is also used to indicate death (of people) or extinction (of species or languages). It is one of the mo ...
Cretaceous bony fish
A dagger, obelisk, or obelus is a typographical mark that usually indicates a footnote if an asterisk has already been used. The symbol is also used to indicate death (of people) or extinction (of species or languages). It is one of the mo ...
Paleogene extinctions Taxa named by Lev Berg