Imported to the Azores as seafood.
Micrograzer « on exposed, wave-beaten rocky shores from the middle to the lower shore » (MarLIN). Synonym: intermedia.
The shell is smaller and much more depressed than those of full-grown specimens of vulgata Linné, with, often, very marked radial ridges, and a tendency to show a posterior margin more angular than round. MarLIN notes « two capricious rays running to the edge » (the rear one); considering the present specimen, this occurrence seems to be reserved to the inner surface, where the radiating pattern is peculiarly contrasting, and restricted to the marginal area, except for two doubled rays that arise from the muscular print.
On rock at low tide, Málaga, Andalucia, S. Spain. 42mm.
Pennant’s description of depressa is not very useful: « P. much depressed; the vertex approximating nearly to one edge. » British Zoology vol. IV, London 1777, p. 142.
Animal cream with a dark gey sole (darker than in vulgata). Shell rather flat with strong radiating sculpture, outside as well as inside near the margins. In adult specimens, the outline is regular like in vulgata or rustica. Above: a young specimen from the shore at Hondarribia, Consorcio Bidasoa-Txingudi, Gipuzkoa Province, N. Spain. Original picture provided by A. Herrero for iNaturalist – (CC BY-NC).
