Mesoglea fairly thin; tentacles long, with large terminal knob. Umbrella 3 mm wide, 4 mm high, cylindrical, walls moderately thick; manubrium 2/3 of bell cavity, nearly all length surrounded by gonads.
Kingdom Animalia Phylum Cnidaria Subphylum Medusozoa Superclass Hydrozoa Class Hydroidomedusae Subclass Anthomedusae Order Capitata Suborder Tubulariida Family Corynidae Genus Sarsia Species Sarsia gracilis
