Orthonychia aculeata (FOSSIL) Barrois, 1889 †
Orthonychia acuta (FOSSIL) F.A. Roemer, 1856 †
Orthonychia acutirostris (FOSSIL) J.W. Hall, 1856 †
Orthonychia aroostooki (FOSSIL) Williams & M. Breger,1916 †
Orthonychia baldwini (FOSSIL) Rohr & al., 1981 †
Orthonychia belli (FOSSIL) A.H. Clarke, 1908 †
Orthonychia bowsheri (FOSSIL) E.L. Yochelson, 1956 †
Orthonychia campanulata (FOSSIL) Barrois, 1889 †
Orthonychia chesterense (FOSSIL) F.B. Meek & A.H. Worthen,1867 †
Orthonychia compressa (FOSSIL) Williams & M. Breger,1916 †
Orthonychia compressum (FOSSIL) Girty, 1910 †
Orthonychia concavum (FOSSIL) J.W. Hall, 1859 †
Orthonychia conicum (FOSSIL) J.W. Hall, 1859 †
Orthonychia conoidea (FOSSIL) G.A. Goldfuss, 1844 †
Orthonychia conoideum (FOSSIL) (Barrois, 1889 †)
Orthonychia cornuforme (FOSSIL) Winchell, 1863 †
Orthonychia cornuta (FOSSIL) Tschernischeff, 1885 †
Orthonychia costata (FOSSIL) Barrois, 1889 †
Orthonychia daschi (FOSSIL) Rohr & Smith, 1978 †
Orthonychia dentalium (FOSSIL) J.W. Hall, 1862 †
Orthonychia dubium (FOSSIL) (Barrois, 1889 †)
Orthonychia egorovi (FOSSIL) Mazaev, 1996 †
Orthonychia elegans (FOSSIL) J. Perner, 1903 †
Orthonychia enorme (FOSSIL) (Lindström, 1884 †)
Orthonychia erectum (FOSSIL) J.W. Hall 1843 †
Orthonychia extensum (FOSSIL) (Barrois, 1889 †)
Orthonychia gracilis (FOSSIL) Mansuy, 1913 †
Orthonychia hebes (FOSSIL) J.W. Hall 1843 †
Orthonychia herzeri (FOSSIL) (Winchell, 1871 †)
Orthonychia inequilaterale (FOSSIL) (Barrois, 1889 †)
Orthonychia infabricatus (FOSSIL) Hyde, 1953 †
Orthonychia ivanovi (FOSSIL) Mazaev, 1996 †
Orthonychia jeffersonensis (FOSSIL) Weller, 1906 †
Orthonychia lodiensis (FOSSIL) J.W. Hall 1843 †
Orthonychia marblecreekensis (FOSSIL) Talent & Philip, 1956 †