(Risso, 1816)
Description
Larval morphology changing with developmental stage; larval development encompasses nine megalopal (or alima) stages. A good description was not available from literature. Giesbrecht, 1910 provides an extended description and illustrations of the subsequent stages and a comparison with the similar stages of Platysquilla eusebia. The medio-ventra spine on the antennular segment is present from the first stage first onwards (TL 3.6-4.1 mm), whereas in P. eusebia this spine appears not until stage 3-4 (TL 3.6-3.9 mm). The ventero-distal spines on abdominal pleurae are present from stage 1 onwards; in P. eusebia these spines appear not until stage 8 (TL 13 mm).
Size
Total larval body length 3.6-22.5 mm.
Depth range/habitat
— Larvae: planktonic, shallow.
—ÊAdult: benthic, subtidally to about 40 metres.
Distribution in the North Sea
In the North Sea, it is restricted to the southern part, entering the area from the Channel.
World distribution
Common in the Mediterranean but is not known from West Africa, although the adult is recorded on the Atlantic coast of Europe northwards to southern British waters.