Anthoathecata

Anthoathecata
Anatomical details of Pandeidae (Filifera). Lower left, top right: Neoturris pileata. Lower right: Stomotoca pterophylla. From Kunstformen der Natur by Ernst Haeckel (1904)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Cnidaria
Class:	Hydrozoa
Subclass:	Hydroidolina
Order:	Anthoathecata Haeckel, 1879
Suborders
Aplanulata Capitata Filifera and see text
Synonyms
Anthomedusa Haeckel, 1879 Anthomedusae Cornelius, 1992 Anthoathecatae Cornelius, 1992 (emendation) Athecata Hincks, 1868 Athecatae Hincks, 1868 (emendation) Gymnoblastea Allman, 1871 Hydromedusa Hydromedusae Laingiomedusae Stylasterina Hickson and England, 1905 Stylasterinae Hickson and England, 1905 (emendation)

Anthoathecata, or the athecate hydroids, are an order of hydrozoans belonging to the phylum Cnidaria. A profusion of alternate scientific names exists for this long-known and heavily discussed group. It has also been called Gymnoblastea and (with or without an emended ending -ae), Anthomedusa, Athecata, Hydromedusa, and Stylasterina. There are about 1,200 species worldwide.^[1]

These hydrozoans always have a polyp stage. Their hydranths grow either solitary or in colonies. There is no firm perisarc around the polyp body. The medusae, or jellyfish, are solitary animals, with tentacles arising from the bell margin, lacking statocysts but possessing radial canals. Their gonads are on the manubrium ("handle").^[2]

Except in Eudendriidae and Laingiidae, prey can be captured by discharging harpoon-like structures (desmonemes) from chambers (cnidae) in specialized cells (nematocysts) on the tentacles. In hydrozoans, these are nearly always adhesive and entrapping, rather than puncturing and venomous as in other jellies.^[2]