• Coliates Scudder, 1875 †
• Comates P.F. Reinsch, 1881 † (uncertain)
• Coniates Sturm, 1843 accepted as Coniatus Germar, 1817
• Coscaites Guex, Hungerbühler, Jenks, Taylor & Bucher, 2005 †
• Cosmetes Gistl, 1848 accepted as Chrysoprasis Audinet-Serville, 1834
• Costaea A. Richard in R. de la Sagra, 1850 accepted as Purdiaea Planchon, 1846 [Family: Clethraceae]
• Costaea Tiberi, 1881 (uncertain) [Family: Mollusca (awaiting allocation)]
• Costapex Fedosov, Puillandre, Herrmann, Dgebuadze & Bouchet, 2017 
• Costatia Polenova, 1952 † accepted as Jenningsina Coryell & Malkin, 1936 †
• Cottaites Unger in Endlicher, 1842 † (unaccepted > unavailable name)