Enchoteuthis

{{short description|Genus of Cretaceous cephalopods}} {{Automatic taxobox | fossil_range={{fossil range|Albian|Campanian}} | image = Enchoteuthis_reconstruction.png | image_caption = Reconstructions of the holotype and largest specimens based on ''Muensterella'' and ''Dosidicus'' | taxon = Enchoteuthis | authority = Miller & Walker, 1968<ref name="Miller & Walker 1968">{{cite journal |last1=Miller |first1=H.W. |last2=Walker |first2=M.V. |date=1968 |title=''Enchoteuthis melanae'' and ''Kansasteuthis lindneri'', new genera and species of teuthids, and a sepiid from the Niobrara Formation of Kansas |journal=Transactions of the Kansas Academy of Science |volume=71 |issue=2 |pages=176–183 |doi=10.2307/3627369|jstor=3627369 }}</ref>

| subdivision_ranks = Other species | subdivision = * {{extinct}}'''''E. tonii''''' (Wade, 1993)<ref name="Wade 1993">{{cite journal |last1=Wade |first1=M. |date=1993 |title=New Kelaenida and Vampyromorpha: Cretaceous squid from Queensland |journal=Memoirs of the Association of Australasian Palaeontologists |volume=15 |pages=353–374}}</ref> * {{extinct}}'''''E. cobbani''''' (Larson, 2010) | synonyms_ref = <ref name="Fuchs et al. 2020">{{cite journal |last1=Fuchs |first1=D. |last2=Iba |first2=Y. |last3=Heyng |first3=A. |last4=Iijima |first4=M. |last5=Klug |first5=C. |last6=Larson |first6=N.L. |last7=Schweigert |first7=G. |date=2020 |title=The Muensterelloidea: phylogeny and character evolution of Mesozoic stem octopods |journal=Papers in Palaeontology |volume=6 |issue=1 |pages=31–92 |doi=10.1002/spp2.1254|bibcode=2020PPal....6...31F |s2cid=198256507 }}</ref> | synonyms = *''Kansasteuthis lindneri'' Miller & Walker, 1968 *''Niobrarateuthis walkeri'' Green, 1977<ref name="Green 1977">{{cite journal |last1=Green |first1=R.G. |date=1977 |title=''Niobrarateuthis walkeri'', a new species of teuthid from the Upper Cretaceous Niobrara Formation of Kansas |journal=Journal of Paleontology |volume=51 |issue=5 |pages=992–995}}</ref> *''Muensterella tonii'' Wade, 1993 *''Tusoteuthis cobbani'' Larson, 2010

| type_species_authority=Miller & Walker, 1968 | type_species=†'''''Enchoteuthis melanae''''' }}

'''''Enchoteuthis''''' (meaning "spear squid") is an extinct genus of large enchoteuthine cephalopod that lived during the Cretaceous. Although it and its relative ''Tusoteuthis'' are often compared to squid, both are now thought to be more closely related to modern octopuses. Examination of gladius remains initially yielded an estimated mantle length of about {{cvt|2|m|0}} based on one specimen once described as ''Tusoteuthis longa'', which is close to or equal to that of the modern giant squid, although reclassification of this genus as a muensterelloid results in a longer total length, about {{cvt|3|m|0}}. Three species are currently recognized as valid: ''E. melanae'', ''E. tonii'', and ''E. cobbani''.<ref name="Fuchs et al. 2020"/>

==Etymology== The generic name ''Enchoteuthis'' is derived from the Greek ''enchos'' ("spear") and ''teuthis'' ("squid").<ref name="Miller & Walker 1968"/> The specific name ''melanae'' honors Melanie Bonner, who discovered the holotype.<ref name="Miller & Walker 1968"/> ''E. cobbani'' is named after William Cobban.<ref name="Larson 2010"/>

==Distribution==

''E. melanae'' and ''E. cobbani'' are both known from the Late Cretaceous Western Interior Seaway of North America, with specimens found in Kansas, Wyoming, South Dakota, North Dakota, and Manitoba.<ref name="Larson 2010"/><ref name="Fuchs et al. 2020"/> ''E. tonii'' is known from the Early Cretaceous Eromanga Seaway of Australia.<ref name="Wade 1993"/><ref name="Fuchs et al. 2020"/> An additional unnamed species is known from the Late Cretaceous Paleo-Pacific Ocean of North America, specifically British Columbia and Alaska.<ref name="Fuchs et al. 2020"/><ref>{{cite web |url=https://collections.peabody.yale.edu/search/Record/YPM-IP-038058 |title=YPM IP 038058 |date=n.d. |website=Yale Peabody Museum of Natural History |access-date=31 March 2021}}</ref>

==Taxonomy and Phylogeny==

In analysis of ''Enchoteuthis'' and related fossil coleoid cephalopods, Larson erected the family Enchoteuthididae for ''Enchoteuthis'', ''Tusoteuthis'', ''Niobrarateuthis'' and ''Kansasteuthis''.<ref name="Larson 2010">{{cite journal |last1=Larson |first1=N.L. |date=2010 |title=Fossil coleoids from the Late Cretaceous (Campanian & Maastrichtian) of the Western Interior |journal=Ferrantia |volume=59 |pages=78–113}}</ref> However ''Kansasteuthis'' has since been deemed a subjective junior synonym of ''Enchoteuthis'' while ''Tusoteuthis'' is considered a nomen dubium.<ref name=":0">{{Cite journal |last=Fuchs |first=Dirk |last2=Iba |first2=Yasuhiro |last3=Heyng |first3=Alexander |last4=Iijima |first4=Masaya |last5=Klug |first5=Christian |last6=Larson |first6=Neal L. |last7=Schweigert |first7=Günter |date=2020 |title=The Muensterelloidea: phylogeny and character evolution of Mesozoic stem octopods |url=https://onlinelibrary.wiley.com/doi/abs/10.1002/spp2.1254 |journal=Papers in Palaeontology |language=en |volume=6 |issue=1 |pages=31–92 |doi=10.1002/spp2.1254 |issn=2056-2802|url-access=subscription }}</ref>

Muensterelloids have traditionally been identified as being closely related to teudopseids, a clade that includes the majority of known gladius-bearing Mesozoic cephalopods. In 1990 Engeser for the first time considered the relationship of the Muensterelloidea to the Octopoda, which includes all modern cirrate and incirrate octopus. Fuchs et al. (2020) found Muensterelloids to be sister taxa to the Palaeololiginidae. The very same analysis finds Muensterelloids, which have never been found to be paraphyletic, to consist of two main clades, the Patelloctopodidae and the ‘''Muensterella''–Enchoteuthidae clade’. The unusual morphology of the gladius in ''Patelloctopus ilgi'' links the morphology seen in teudopseids like ''Muensterella'' and crown cirrates and incirrates. It is possible that the patelloctopodid clade includes the last common ancestor of cirrate and incirrate octopods, whereas the "Muensterella-Enchoteuthidae" clade likely became extinct during the Late Cretaceous. Presumably, these two clades split in the middle-late Toarcian, which would make it congruent with the minimum divergence date calculated by Tanner et al. (2017) using molecular clock analysis.<ref name=":0" />

The results of the 2020 analysis show Enchoteuthis as the most derived member of the "''Muensterella''-Enchoteuthidae" clade:{{clade|{{clade |1={{clade |1=''Teudopsis acuta'' |2={{clade |1=''Palaeololigo albersdoerferi'' |label2=Muensterelloidea |2={{clade |1=''Celaenoteuthis incerta''|style1=background-color:#fff5f5|barbegin1=pink |2={{clade |1=''Engeseriteuthis arcuatus''|style1=background-color:#fff5f5|bar1=pink |2={{clade |1={{clade |1=''Listroteuthis conica''|style1=background-color:#fff5f5|bar1=pink |2={{clade |1=''Muensterella scutellaris''|style1=background-color:#fff5f5|bar1=pink |2={{clade |1=''Muensterella spinosa''|style1=background-color:#fff5f5|bar1=pink |2={{clade |1=''Muensterella jillae''|style1=background-color:#fff5f5|bar1=pink |2={{clade |1=''Muensterella sp''.|style1=background-color:#fff5f5|barend1=pink |label2=Enchoteuthidae |2={{clade |1=''Niobrarateuthis bonneri'' |2={{clade |1=''Enchoteuthis melanae'' |2={{clade |1=''Enchoteuthis cobbani'' |2=''Enchoteuthis tonii'' }} }} }} }} }} }} }} }} |2={{clade |1=''Tyrionella fauseri''|style1=background-color:#fff5f5|barbegin1=pink |2={{clade |1=''Etchesia martilli''|style1=background-color:#fff5f5|bar1=pink |2={{clade |1=''Muensterellina johnjagti''|style1=background-color:#fff5f5|barend1=pink |2={{clade|state2=dashed |label1=Patelloctopodidae |1={{clade |1=''Pearceiteuthis buyi'' |2=''Patelloctopus ilgi'' }} |label2=Palaeoctopodidae |sublabel2=(Relationship with Patelloctopodidae is assumed only) |2={{clade |1={{clade |1=''Keuppia hyperbolaris'' |2=''Keuppia levante'' }} |2=''Palaeoctopus newboldi'' |3=''Styletoctopus annae'' }} }} }} }} }} }} }} }} }} }} }}|style=font-size: 90%; line-height:100%|grouplabel1={{Clade labels|label1='Muensterellidae'|top1=30%|color1=pink}}|label1='''Vampyromorphida'''}}

==See also== {{Portal|Paleontology}} *''Tusoteuthis'' *''Muensterella'' *Cephalopod size

==References== {{Reflist}}

{{Taxonbar|from=Q106462802}} Category:Late Cretaceous cephalopods of North America Category:Octopuses Category:Prehistoric cephalopod genera Category:Fossil taxa described in 1968