Gracilineustes

{{Short description|Extinct genus of reptiles}} {{Use dmy dates|date=April 2022}} {{Automatic taxobox | fossil_range = Callovian - Kimmeridgian, {{Fossil range|167|155}} | image = Gracilineutes leedsi FMNH.jpg | image_caption = Fossil skull of ''G. leedsi'', NHMUK PV R5793, at the Field Museum of Natural History | taxon = Gracilineustes | authority = Young ''et al''., 2010 | type_species = †'''''Gracilineustes leedsi''''' | type_species_authority = (Andrews, 1913)<ref name="Andrews, 1913">Andrews CW. 1913. ''A descriptive catalogue of the marine reptiles of the Oxford Clay, Part Two''. London: British Museum (Natural History), 206 pp.</ref> | subdivision_ranks = Other species | subdivision = * †''G. acutus'' <small> Lennier, 1887 <ref name="Lennier, 1887">Lennier G. 1887. Description des fossiles du Cap de la Hève. ''Bulletin de la Société Géologique de Normandie, Le Havre'' '''12''': 17-98.</ref></small> | synonyms = *''Metriorhynchus laeve'' <small>Andrews, 1913</small> }} left|thumb|Holotype of ''G. leedsi'', NHMUK PV R3540 thumb '''''Gracilineustes''''' is an extinct genus of marine crocodyliform that lived in the oceans during the Middle to Late Jurassic. ''Gracilineustes'' was a carnivore that spent much, if not all, its life out at sea. It was a small reptile, with ''G. leedsi'' measuring {{cvt|2.25|-|3.11|m|ft}} long and ''G. acutus'' measuring {{cvt|3.77|m|ft}} long.<ref>{{cite journal|year=2011|last1=Young|first1=M.T.|last2=Bell|first2=M.A.|last3=de Andrade|first3=M.B.|last4=Brusatte|first4=S.L.|title=Body size estimation and evolution in metriorhynchid crocodylomorphs: implications for species diversification and niche partitioning|journal=Zoological Journal of the Linnean Society|volume=163|issue=4|pages=1199–1216|doi=10.1111/j.1096-3642.2011.00734.x|doi-access=free}}</ref> thumb|Skull and limb of ''G. leedsi'' ==Discovery and species== Fossil specimens referrable to ''Gracilineustes'' are known from Middle-Late Jurassic deposits of England and France.<ref name="Youngetal.2010">Young, Mark T., Brusatte, Stephen L., Ruta, M., Andrade, Marco B. 2009. "The evolution of Metriorhynchoidea (Mesoeucrocodylia, Thalattosuchia): an integrated approach using geometrics morphometrics, analysis of disparity and biomechanics". ''Zoological Journal of the Linnean Society'' '''158''': 801-859.</ref>

===Valid species=== *''G. leedsi'': Western Europe (England) of the Middle Jurassic (Callovian);<ref name="Andrews, 1913"/> ''Metriorhynchus laeve'' is a junior synonym. *''G. acutus'': Western Europe (France) of the Late Jurassic (Kimmeridgian) <ref name="Lennier, 1887"/>

==Classification==

''Gracilineustes'' is an early member of the metriorhynchid subfamily Metriorhynchinae. The cladogram below is from an analysis by Mark Young and colleagues in 2020.<ref name="Youngetal.2020">{{cite journal |last1=Young |first1=M. T. |last2=Brignon |first2=A. |last3=Sachs |first3=S. |last4=Hornung |first4=J. J. |last5=Foffa |first5=D. |last6=Kitson |first6=J. J .N. |last7=Johnson |first7=M. M. |last8=Steel |first8=L. |year=2020 |title=Cutting the Gordian knot: a historical and taxonomic revision of the Jurassic crocodylomorph ''Metriorhynchus'' |journal=Zoological Journal of the Linnean Society |volume=192 |issue=2 |pages=510–553 |doi=10.1093/zoolinnean/zlaa092 |doi-access=free}}</ref>

{{Clade|{{clade |1=''Thalattosuchus superciliosus'' |2={{clade |1={{clade |1=''Gracilineustes acutus'' |2=''Gracilineustes leedsi''}} |2={{clade |1={{clade |1=''Maledictosuchus nuyivijanan'' |2=''Maledictosuchus riclaensis''}} |2={{clade |1=''Metriorhynchus brevirostris'' |label2=Rhacheosaurini |2={{clade |1={{clade |1=''"Metriorhynchus" palpebrosus'' |2={{clade |1=''"Cricosaurus" saltillensis'' |2={{clade |1=Swiss rhacheosaurin |2=Cretaceous rhacheosaurin}}}}}} |2={{clade |1=Metriorhynchinae indet. (Cuba) |2={{clade |1={{clade |1=''Rhacheosaurus gracilis'' |2=''cf. Cricosaurus''}} |label2=''Cricosaurus'' |2={{clade |1={{clade |1=''Cricosaurus bambergensis'' |2={{clade |1=Solnhofen ''Cricosaurus'' |2={{clade |1=''Cricosaurus elegans'' |2=''Cricosaurus suevicus''}}}}}} |2={{clade |1=''Cricosaurus lithographicus'' |2={{clade |1=''Cricosaurus araucanensis'' |2={{clade |1=''Cricosaurus vignaudi'' |2=''Cricosaurus schroederi'' }}}}}}}}}}}}}}}}}}}}}}|label1=Metriorhynchinae}}

==References== {{Reflist}}

Category:Late Jurassic crocodylomorphs of Europe Category:Middle Jurassic crocodylomorphs Category:Prehistoric pseudosuchian genera Category:Prehistoric marine crocodylomorphs Category:Fossil taxa described in 2010 Category:Middle Jurassic genus first appearances Category:Late Jurassic extinctions Category:Thalattosuchia Category:Oxford Clay