After Turner, Burrow & Warren, 2005

<==o †Gyracanthidae Woodward, 1906
   |?- †Antacanthus insignis Dewalque, 1877 [non Antacanthus Rich. ex DC. (= Scolosanthus Vahl (Angiosperma: Rubiaceae))]; Miss. Eu. 
   |?- †Aganacanthus striatulus Traquair, 1884; Miss. Eu. 
   |?-o †Oracanthus Agassiz, 1843; Miss. NA. Eu. [Phoderacanthus Davis, 1883]
   |  |-- †O. milleri Agassiz, 1843
   |  |-- †O. minor Agassiz, 1837
   |  |-- †O. pnigeus Newberry & Worthen, 1866
   |  `-- †O. pustulosus Agassiz, 1837
   |--o †Gyracanthus Agassiz, 1837; L.Dev.-Penn. NA., ?L.Dev.-Penn. Eu.
   |  |?- †“G.alleni Newberry, 1873
   |  |?- †“G.alnwicensis Agassiz, 1837
   |  |?- †“G.compressus Newberry, 1873
   |  |?- †“G.”? convexus Gross, 1933
   |  |?- †“G.”? cordatus St. John & Worthen, 1883
   |  |?- †“G.denticulatus Davis, 1880
   |  |?- †“G.duplicatus Dawson, 1868
   |  |?- †“G.falciformis Traquair, 1902
   |  |?- †“G.incurvus Traquair, 1890
   |  |?- †“G.inornatus Newberry, 1889 (nomen dubium)
   |  |?- †“G.maccalliensis Mensah & Smit, 1972 (nomen nudum)
   |  |?- †“G.nobilis Traquair, 1884 [=? Aganacanthus striatulus Traquair, 1884]
   |  |?- †“G.obliquus M´Coy, 1848
   |  |?- †“G.ornatus Agassiz, 1843 (nomen nudum)
   |  |?- †“G.parvulus Bryant, 1929
   |  |?- †“G.primaevus Eastman, 1908
   |  |?- †“G.rectus Traquair, 1890
   |  |?- †“G.sarlei Hussakof & Bryant, 1918
   |  |?- †“G.sherwoodi Newberry, 1889
   |  |?- †“G.seriponensis Gagnier in Gagnier et al., 1988
   |  |-- †G. formosus Agassiz, 1837 [†G. tuberculatus Agassiz, 1843 in Agassiz, 1833-44]
   |  |-- †G. magnificus Dawson, 1868
   |  |-- †G. youngi Traquair, 1883
   |  `-- †G. rothrocki Wells & Blickle, 1943
   `--o †Gyracanthides Woodward, 1906; Miss. Aus.
      |-- †G. murrayi Woodward, 1906
      |-- †G. warreni White, 1968
      `-- †G. hawkinsi Turner, Burrow & Warren, 2005 [G. sp. cf. G. murrayi Thulborn et al., 1996]

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