• Caerellia Simon, 1880 accepted as Solpuga Lichtenstein, 1796
• Carelia A.L. Jussieu ex Cavanilles, 1803 accepted as Mikania Willdenow, 1803 [Family: Asteraceae]
• Carelia Adams, 1855 [Family: Amastridae]
• Carelia Fabricius, 1759 (uncertain) [Family: Asteraceae]
• Carelia Lessing, 1832 (unaccepted) [Family: Asteraceae]
• Cemalia Özdikmen, 2010 †
• Cephalia Meigen, 1826 [Phylum: Arthropoda]
• Cephalia S.C.D. Sah & R.K. Kar, 1974 † [Phylum: Acritarcha]
• Ceracia Rondani, 1865
• Ceradia J. Lindley, 1845 (uncertain)
• Ceraia Brunner, 1891 [Family: Tettigoniidae]
• Ceraia Loureiro, 1790 accepted as Dendrobium O. Swartz, 1799 [Family: Orchidaceae]
• Cerala Hampson, 1912 accepted as Kerala Moore, 1881
• Ceramia D. Don, 1834 (uncertain)
• Cerania S.F. Gray, 1821 accepted as Thamnolia Acharius ex Schaerer, 1850 [Family: Icmadophilaceae]
• Cerania Weise, 1893 accepted as Aulacophora Chevrolat in Dejean, 1836 [Family: Chrysomelidae]
• Ceraria Pearson & Stephens, 1912
• Ceratia Adanson, 1763 (uncertain) [Family: Fabaceae]
• Ceratia Chapuis, 1876 accepted as Aulacophora Chevrolat in Dejean, 1836 [Family: Chrysomelidae]
• Ceratia H. Adams & A. Adams, 1852 [Family: Iravadiidae]
• Cercamia Randall & Smith, 1988
• Cercaria O.F. Müller, 1773 (uncertain > nomen dubium)
• Cercolia Casey, 1913 accepted as Trigonarthris Haldeman, 1848
• Cerdaia Monné, 2006
• Cerealis Paetel, 1875 (uncertain)
• Cereatta Staręga, 1992
• Cereaxina Jeannel, 1934
• Cereola Nardo, 1847 (uncertain)
• Ceresia Persoon, 1805 accepted as Paspalum Linnaeus, 1759 [Family: Poaceae]
• Ceresia Uvarov, 1928 [Family: Tettigoniidae]
• Cermatia Illiger in Rossi, 1807 accepted as Scutigera Lamarck, 1801
• Cerullia † (uncertain)
• Cervaria Gray, 1867 accepted as Lynx Kerr, 1792 [Family: Felidae]
• Cervaria Linnaeus, 1787 (unaccepted) [Family: Caryophyllaceae]
• Cervaria N.M. Wolf, 1776 accepted as Peucedanum Linnaeus, 1753 [Family: Apiaceae]
• Cervaria Walker, 1866 [Family: Tineidae]
• Cervilia Frickhinger, 1916
• Cetrelia W.L. Culberson & C.F. Culberson, 1968
• Circalia Haeckel, 1888 (uncertain)
• Cloealia Beck, 1847 (uncertain)
• Cordalia Gobi, 1885 accepted as Tuberculina Tode ex P.A. Saccardo, 1880 [Family: Helicobasidiaceae]
• Cordalia Jacobs, 1924 [Family: Staphylinidae]
• Cornalia Gray, 1858 (uncertain) [Family: Bryozoa (awaiting allocation)]
• Cornalia Lavy, 1830 (uncertain) [Family: Brassicaceae]
• Corralia Roewer, 1913 [Family: Gonyleptidae]
• Corralia Walcott, 1920 † (uncertain) [Family: Porifera (awaiting allocation)]
• Crealia Gray, 1858 (uncertain)