Paracestracion

{{Short description|Extinct genus of sharks}} {{automatic taxobox | fossil_range = Early Jurassic-Early Cretaceous, {{fossilrange|182.7|132.9}} | image2 = Paracestracion falcifer 2.jpg | image2_caption = ''Paracestracion falcifer'' fossil from Solnhofen, Germany | image = Paracestracion danieli.png | image_caption = Holotype specimen of ''Paracestracion danieli'' | taxon = Paracestracion | authority = Koken in Zittel, 1911<ref name=Zittel1911 /> | type_species = {{extinct}}'''''Paracestracion falcifer''''' | type_species_authority = (Wagner, 1858)<ref name=Wagner1857 /> | subdivision_ranks = Other species | subdivision = *†''P. bellis'' Underwood & Ward, 2004<ref name=Ward2004>C. J. Underwood and D. J. Ward. (2004). Neoselachian sharks and rays from the British Bathonian (Middle Jurassic). ''Palaeontology'' 47(3):447-501</ref> *{{extinct}}''P. danieli'' Slater, 2016 *†''P. pectinatus'' Guinot ''et al.'', 2014<ref name=Guinot2014>{{aut|Guinot, G.}}; {{aut|Cappetta, H.}}; {{aut|Adnet, S.}} (2014): A rare elasmobranch assemblage from the Valanginian (Lower Cretaceous) of southern France. ''Cretaceous research'' 48: 54–84. {{doi|10.1016/j.cretres.2013.11.014}}</ref> *†''P. sarstedtensis'' (Thies, 1983)<ref name=Thies1983 /> *†''P. viohli'' Kriwet, 2008<ref name=Kriwet2008>J. Kriwet. (2008). A new species of extinct bullhead sharks, ''Paracestracion viohli'' sp. nov. (Neoselachii, Heterodontiformes), from the Upper Jurassic of South Germany. ''Acta Geologica Polonica'' 58(2):235-241</ref> | synonyms = *''Cestracion falcifer'' Wagner, 1857<ref name=Wagner1857 /> *''Heterodontus sarstedtensis'' Thies, 1983<ref name=Thies1983 /> }}

'''''Paracestracion''''' is an extinct genus of heterodontiform sharks from Early Jurassic to Early Cretaceous-aged rocks of England, France, Germany and Luxembourg. The genus was first described in 1911 by Ernst Hermann Friedrich von Koken in Karl Alfred von Zittel.<ref name="Zittel1911">Zittel, K. A., (1911): ''Grundzüge der Paläontologie (Paläozoologie).'' Neubearbeitet von F. Broili, E. Koken, M. Schlosser. II. Abteilung. Vertebrata. Oldenbourg 1911. Zweite vermehrte und verbesserte Auflage. Gr.8°. VII, 598 S.</ref>

The genus contains several Late Jurassic species known from well preserved full body remains, which show that it differs from the living bullhead sharks in the placement of the pelvic girdle and fins, as well as by having a shorter skull.<ref name=":02">{{Cite journal |last1=Slater |first1=Tiffany S. |last2=Ashbrook |first2=Kate |last3=Kriwet |first3=Jürgen |date=August 2020 |editor-last=Cavin |editor-first=Lionel |title=Evolutionary relationships among bullhead sharks (Chondrichthyes, Heterodontiformes) |url=https://onlinelibrary.wiley.com/doi/10.1002/spp2.1299 |journal=Papers in Palaeontology |language=en |volume=6 |issue=3 |pages=425–437 |bibcode=2020PPal....6..425S |doi=10.1002/spp2.1299 |issn=2056-2799 |s2cid=214133104 |hdl=10468/10339|hdl-access=free }}</ref><ref>{{Cite journal |last1=Villalobos-Segura |first1=Eduardo |last2=Stumpf |first2=Sebastian |last3=Türtscher |first3=Julia |last4=Jambura |first4=Patrick |last5=Begat |first5=Arnaud |last6=López-Romero |first6=Faviel |last7=Fischer |first7=Jan |last8=Kriwet |first8=Jürgen |date=2023-03-08 |title=A Synoptic Review of the Cartilaginous Fishes (Chondrichthyes: Holocephali, Elasmobranchii) from the Upper Jurassic Konservat-Lagerstätten of Southern Germany: Taxonomy, Diversity, and Faunal Relationships |journal=Diversity |language=en |volume=15 |issue=3 |pages=386 |doi=10.3390/d15030386 |issn=1424-2818 |pmc=7614348 |pmid=36950327 |doi-access=free }}</ref>

== Taxonomy == Recent studies have classified it into its own family, '''Paracestracionidae'''.<ref name=":02"/>

At maximum, the genus contains five species: ''P. bellis'' from the Bathonian of England,<ref name="Ward2004" /> the type species ''P. falcifer'' from the Tithonian and Kimmeridgian of Weymouth, England and Solnhofen, Germany, which was originally named as a species of ''Cestracion'' (now seen as a synonym of ''Heterodontus'') in 1857 by Johann Andreas Wagner,<ref name="Wagner1857">Wagner, J. A. (1857) Characteristics of new species of cartilage fish from the lithographic slates of the Solnhofen area. ''Gelehrte Anzeigen der königlich bayerischen Akademie der Wissenschaften'', 44 (35,36): 288–293 [in German]</ref> ''P. sarstedtensis'', originally classified as a species of ''Heterodontus'', from the Toarcian and Aalenian of Germany,<ref name="Thies1983">D. Thies. (1983). (Jurassic neoselachians from Germany and S[outh]-England). ''Courier Forschungsinstitut Senckenberg'' 58:1-116 [in German]</ref> and ''P. viohli'' from the Tithonian-aged Painten Formation of Germany,<ref name="Kriwet2008" /><ref>{{citation |last=Arrati |first=G |year=2000 |title=Remarkable teleostean fishes from the Late Jurassic of southern Germany and their phylogenetic relationships |journal=Mitteilungen aus dem Museum für Naturkunde in Berlin, Geowissenschaften Reihe |volume=3 |issue=1 |pages=137–179|doi=10.5194/fr-3-137-2000 |doi-access=free |bibcode=2000FossR...3..137A }}</ref> with a sixth indeterminate species known from the Toarcian-aged ''Variabilis'' layer of the La Couche à Crassum (part of the larger Posidonia Shale) of Luxembourg.<ref>D. Delsate and R. Weis. (2010). La Couche à Crassum (Toarcien moyen) au Luxembourg: stratigraphie et faunes de la coupe de Dudelange-Zoufftgen. ''Ferrantia'' 62:35-62</ref> ''P. pectinatus'' from the Early Cretaceous (Valanginian) of France has been described on the basis of isolated teeth.<ref name="Guinot2014" />

==References== {{reflist}}

Category:Taxa named by Johann Andreas Wagner Category:Heterodontiformes Category:Fossil taxa described in 1911 Category:Jurassic sharks Category:Cretaceous sharks Category:Toarcian first appearances