Bryozoa orders

Cyclostomatida, or cyclostomata (also known as cyclostomes), are an ancient order of stenolaemate bryozoans which first appeared in the Lower Ordovician. It consists of 7+ suborders, 59+ families, 373+ genera, and 666+ species. The cyclostome bryozoans were dominant in the Mesozoic; since that era, they have decreased. Currently, cyclostomes seldom constitute more than 20% of the species recorded in regional bryozoan faunas.

Cheilostomatida, also called Cheilostomata, is an order of Bryozoa in the class Gymnolaemata.

REDIRECT Phylactolaemata

The Ctenostomatida are an order of bryozoans in the class Gymnolaemata. The great majority of ctenostome species are marine, although Paludicella inhabits fresh water. They are distinguished from their close relatives, the cheilostomes, by their lack of a calcified exoskeleton. Instead, the exoskeleton is chitinous, gelatinous, or composed only of a soft membrane, and always lacks an operculum. Colonies of ctenostomes are often composed of elongated, branch-like stolons, although more compact forms also exist.