Their two body forms are the medusa and polyp.
One member of this phylum, Chironex fleckeri, is the most dangerous venomous species. Their bodies consist of mesoglea between two one-cell-thick epithelial layers, and one characteristic feature of this phylum is divided into three classes, including ptychocysts, which build protective tubes for a type of anemone. The subphylum anthozoa includes corals, and sea wasps are included in class cubozoa. Their two body forms are the medusa and polyp. For 10 points, name this phylum named for their stinging cells, which includes Portuguese men-of-war and jellyfish.
One member of this phylum, Chironex fleckeri, is the most dangerous venomous species.
{Cnidaria} [{nih}-{DAR}-{ee}-{uh}]