The medusae of the Tubulariidae are all characterised by having a simple circular mouth, and gonads completely surrounding the stomach; there are no ocelli at the bases of the marginal tentacles. The umbrella is simple and has never more than four marginal tentacles, which are usually conspicuous for their heavy nematocyst armature. The medusa stages of the following tubulariid species are unknown (Hansson, 1998a):
¥ Tubularia larynx Ellis and Solander, 1786 (= Ectopleura larynx) — the polyp occurs from the lower shore to at least 100 m depth and is common in the whole North Sea. Detached hydranths were occasionally found in the neritic plankton of the Dutch Waddenzee.
¥ Tubularia bellis Allman, 1863 — the polyp occurs in the lower eulittoral and is common in the whole North Sea.
¥ Tubularia indivisa Linnaeus, 1758 — the polyp occurs from 0 to at least 280 m depth and is common in the whole North Sea.
¥ Tubularia regalis Boeck, 1860 — depth range unknown; concerning the North Sea, the polyp possibly occurs in the Oslofjorden; in the Atlantic Ocean it is found in the NE Atlantic, NE Greenland, Shetlands, along the Norway coast, Spitzbergen, and Nova Zembla.