An order of the subphylum Sporozoa characterized by having small spores and one polar capsule. Common occurrence is as parasites of arthropods and fish. Includes nosema. In finfish may cause xenomas, in crustaceans cause ‘cotton flesh’.

Saunders Comprehensive Veterinary Dictionary 3rd Edition. Copyright © 2007 by D.C. Blood, V.P. Studdert and C.C. Gay, Elsevier. All rights reserved.