The
Myxozoa (
etymology:
Greek: μύξα
myxa "slime" or "mucus" + thematic vowel o + ζῷον
zoon "animals") are a group of aquatic
parasitic animals. Over 1300 species have been described and many have a two-host lifecycle, involving a
fish and an
annelid worm or
bryozoan. The average size of a
myxosporean spore usually ranges from 10 μm to 20 μm whereas that of a malacosporean spore can be up to 2 mm. Myxozoans can live in both fresh and marine habitats.