(Keferstein and Ehlers, 1861)
Description
Umbrella apically with thick flat lens-shaped jelly, jelly thinner in distal portion [S.corona-habitus ]; margin with up to 35 (or more?) rectangular lappets, about twice as long as broad; otoporpae absent; velum well-developed. Peripheral canal system absent.
Manubrial pouches absent, periphery of manubrium circular and unbroken, covering whole lower surface of lens-shaped portion of umbrella; mouth simple, circular.
Simple annular gonads surrounding manubrium.
Up to 35 (or more) stiff solid marginal tentacles; leaving umbrella at level of periphery of manubrium. [S.corona-b/w ] Marginal lappets usually with 2 statocysts mounted on large cushion with long bristles.
Size
Umbrella 12-15 mm wide.
Colour
Whole medusa usually colourless except for statocyst concretions. Marginal tentacles red or yellow; gonads rose-coloured; statocyst concretions yellowish or rose.
Ecology and depth range
Holopelagic; epipelagic.
Distribution in the North Sea
Reported from the English Channel and the northern North Sea, where it is present as a result of Atlantic drift; carried to the southern Norwegian coast in the autumn when the Atlantic Current increases in volume and velocity.
World distribution
North Atlantic, Mediterranean Sea; E South Atlantic and Indo-Pacific Oceans.
Remark
Polyp stage absent
[After Russell, 1953a; Russell, 1981b; Kramp, 1959; Bouillon, 1999]