M. Sars, 1835
Description
Umbrella bell-shaped, nearly twice as high as broad; jelly thick; no exumbrellar nematocyst tracks. Umbrella margin horizontal; velum fairly wide; pointed apical process present with an apical canal. Four radial canals and ring canal fairly broad [C.nutans-medusa ].
One stout perradial tentacle without ocelli on tentacle bulb, nematocyst armature grouped in annulations; three perradial non-tentacular bulbs forming exumbrellar spurs.
Short gastric peduncle present. Manubrium large, cylindrical, about 2/3 of length bell cavity. Mouth circular, simple, armed with nematocysts. Gonads completely surrounding manubrium, leaving mouth and peduncle free.
Size
Maximum height 6 mm.
Colour
Very variable [C.nutans-habitus], marginal tentacle, marginal bulbs and stomach light pink, flecked with carmine, bright yellow, straw coloured or reddish brown; sometimes brown granules at apex of stomach. Apical process often pinkish; subumbrella sometimes suffused with pink; radial canals and ring canal with bright yellow pigment.
Ecology and depth range
Neritic, temperate-boreal. The medusa stage is not long-lived, probably not exceeding two months, and in SW British waters a common member of spring plankton. Period of occurrence may vary slightly from year to year and in the north tends to be slightly later
Distribution in the North Sea
All North Sea coasts.
World distribution
European coasts, from Iceland and the Faeroe Islands in the north to the Mediterranean and Black Sea in the South.
[After Russell, 1939; Russell, 1953a; Kramp, 1959]