coup de grÃ¢ce in British English. See all translations. coup de grÃ¢cenoun [ S ] uk â /ËkuË dÉ ËÉ¡rÉËs/ us â /ËkuË dÉ ËÉ¡rÉËs/ formal. âº an action that ends something that has been gradually getting worse, or that kills a person or animal in order to end their suffering: Jane's affair was the coup de grÃ¢ce to her disintegrating marriage. Thesaurus: synonyms and related words.
Bivalves is a class of marine and freshwater molluscs with about 30,000 species including scallops, clams, oysters, razor shells, shipworms and mussels. Most bivalves are marine usually found in shallower water but some live in brackish and freshwater.
Bivalves include clams, oysters, cockles, mussels, scallops, and numerous other families that live in saltwater, as well as a number of families that live in freshwater. The majority are filter feeders. The gills have evolved into ctenidia, specialised organs for feeding and breathing.ost bivalves are filter feeders, using their gills to capture particulate food such as phytoplankton from the water. The protobranchs feed in a different way, scraping detritus from the seabed, and this may be the original mode of feeding used by all bivalves before the gills became adapted for filter feeding.