Umbrella 8-10 mm wide, with conical apical thickening; gonads linear or oval, on middle third of 8 radial canals; one statocyst next to each perradialtentacle and interradialcirrus.
Kingdom Animalia Phylum Cnidaria Subphylum Medusozoa Superclass Hydrozoa Class Hydroidomedusae Subclass Trachymedusae Family Rhopalonematidae Genus Rhopalonema Species Rhopalonema velatum