Early reports on dinoflagellate infestations of tintinnine ciliates established the taxonomic affinity of the parasite and emphasized the morphology and development of the dinospore, a flagellated dispersal stage. However, sufficient morphological criteria to distinguish species were not furnished and dinoflagellate infestations reported for a variety of tintinnine hosts were attributed to a single organism, Duboscquella tintinnicola. Grass, [reported by Chatton ] recognized morphological variations among spores resulting from different infestations and described a second species, D. anisospora, characterized by dinospores of unequal size and a trophont that had a curiously ribbed surface. Most recently, Cachon examined the life cycle and cytology of several Duboscquella spp. and stressed differences in trophont morphology as criteria for differentiating species. He expanded the genus to include five new species and reported infestations from a variety of planktonic protists including non-tintinnine ciliates and dinoflagellates.

Duboscquella infestations of tintinnine ciliates are passively transmitted when dinospores are ingested by susceptible hosts. Once inside the host, spores lose their flagella, differentiate into trophonts, and enter an extended growth phase. The episome (= epicone) of the trophont is covered by a thickened cuticle, the shield, which is limited peripherally by a fibrous ring, the perinema. Smaller fibers emanate from the perinema and extend beneath the shield. These fibers are organized in species specific patterns and are usually associated with furrows or grooves in the shield. The lamina pharyngea, a funnel-shaped skeletal structure of uncertain function, is attached to the perinema and marks the ventral surface of the parasite. In several Duboscquella species, final growth of the trophont involves an elaborate morphogenetic process that results in the phagocytosis of a substantial portion of the host cytoplasm, however other species consume the host without forming a food vacuole. In either case, the trophont phase is followed by palintomic sporogenesis (i.e., successive nuclear and cytoplasmic divisions without interruption; = palintomy) which produces numerous biflagellate spores. Both macrospores and microspores may be formed by the same species, but only one type is released from a given host.