Evolution of Conoidea classification. Cone snail, turrid, and terebrid shells that make up the Conoidean superfamily are depicted. A. Conoidea classification based on shell and radula characters (e.g. [8, 57]). B. Conoidea classification based mainly on anatomical characters (). ST = Strictispiridae; DR = Drilliidae; PS = Pseudomelatomidae. C. Conoidea classification with molecular characters. Two main clades are defined, but a formal classification has not yet been proposed.