Multivalvulida is an order of

myxozoa Myxozoa (etymology: Greek: μύξα ''myxa'' "slime" or "mucus" + thematic vowel o + ζῷον ''zoon'' "animal") is a subphylum of aquatic cnidarian animals – all obligate parasites. It contains the smallest animals ever known to have lived. O ...

Families

Kudoidae ''Kudoa'' is a genus of Myxozoa and the only genus recognized within the monotypic family Kudoidae. There are approximately 100 species of ''Kudoa'' all of which parasitize on marine and estuarine fish. ''Kudoa'' are most commonly known and studi ...

* Spinavaculidae * Trilosporidae

References

Encyclopedia of Life entry
Myxosporea Cnidarian orders {{Myxozoa-stub