Definition
Acnidosporidia is a class of microscopic parasitic protozoa that primarily infect invertebrates, particularly insects and aquatic organisms. These parasites lack a distinct spore-forming stage with a protective shell (cnidocyst), unlike their relatives in Myxozoa. Think of Acnidosporidia as stealthy invaders that sneak into their hosts without leaving obvious traces, unlike some other parasites that form resistant spores. Their life cycle often involves complex interactions with the host's cells. They are significant in the context of invertebrate health and ecology. Studying Acnidosporidia can provide insights into parasite evolution and host-parasite interactions.