Patella ulyssiponensis

Patella ulyssiponensis, common name the rough limpet, or China limpet is a species of sea snail, a true limpet, a marine gastropod mollusk in the family Patellidae, one of the families of true limpets. Compared with the common limpet, Patella vulgata, the rough limpet has a similar shell (maximum size 50mm long x 40 mm wide x 20 mm high, apex closer to the front of the animal/ anterior than to the back/ posterior) but with radiating ridges that are finer and which alternate 1-ridge/ 3-ridges around the shell in a distinct pattern. The interior of the shell is often tinged orange towards its apex. The foot is a cream-orange color, and the dozens of pallial tentacles are translucent and colorless, arranged in two series of different sizes. No other characteristics of body structure or shell morphology distinguish it from P. vulgata, to which it is otherwise identical. In Madeira Island in Portugal, Patella ulyssiponensis, known locally as Lapa, is eaten after cooking in a pan with garlic and lemon juice.