Edwards, 1983
Description
Umbrella bell-shaped, upper half slightly conical as the jelly is especially thick apically [Sarsia piriforma ]. Velum broad. Exumbrella of young medusa with a few rather large nematocysts in eight adradial groups and a few around the apical region.
Four radial canals very narrow in young medusa which also has an umbilical canal; radial canals in mature specimens jagged and irregular in width, sometimes very broad. Apical knob conical, of variable height. Subumbrellar pockets between the canals shallow and rounded (or absent?); interradial exumbrellar furrows shallow.
Manubrium long, about twice as long as length of bell cavity.
Gonads continuous, surrounding apical 2/3 of manubrium; only the long capacious mouth and a short basal portion of the manubrium are gonad-free. Four marginal tentacles long and hollow, about twice umbrella height; with spirally arranged nematocyst clusters and terminally a large hollow globular mass armed with nematocysts. Tentacle bulbs each with an aboral ocellus.
Size
Upon release from the hydroid the umbrella is about 0.9 mm in diameter, in culture mature medusae may reach a maximum size of about 8.2 mm high by 7.3 mm wide.
Colour
Endoderm of apical knob and tentacle bulbs scarlet or orange; ocelli black.
Ecology and depth range
Edwards (1983) observed these medusae reared in culture where they proved not to be active swimmers, floating near or often laying on the bottom. This may indicate that in nature these medusae do not inhabit the surface layers but probably live near the bottom or in deeper water. According to Edwards, 1983, the meduse has never been found in the marine plankton.
Hydroid found at depths of 15-20 m.
Distribution in the North Sea
Northern North Sea
World distribution
E North Atlantic.
[After Edwards, 1983; Schuchert, 2001]