The grooved carpet shell, or Palourde clam, Ruditapes decussatus, or Venerupis decussatus, is a clam (bivalve mollusc) in the family Veneridae. It is distributed worldwide and is highly prized due to its ecological and economic interest. It has been proposed as a bioindicator.
This species is one of the most popular and profitable mollusks of lagoonal and coastal sites in the Mediterranean and adjoining Atlantic coast where it has been collected since a long time ago as food. It is consumed fresh and canned. Several dishes like Spaghetti alle vongole and the Portuguese Amêijoas à Bulhão Pato, make use of it.