The Gregarinidæ, when you look at the widest good sense, as a class of protozoans, divided in to Monocystidea or simple-celled gregarines, and Dicystidea or septate gregarines: nearly synonymous with Sporozoa (which see). See Gregarinidæ, Gregarinidea. Also known as Cytozoa.
How would you define gregarinida?