Conoidasida is a class of parasitic protists. The class was defined in 1988 by Levine and contains two subclasses - the coccidia and the gregarines. All members of this class have a complete, hollow, truncated conoid. Gregarines tend to parasitize invertebrates with the mature gamonts being extracellular, the coccidia mostly infect vertebrates and have intracellular gamonts.