Heart Cockle

Known as the Heart Cockle because of its shape, this species scientific name is Maoricardium pseudolima (described by Lamarck in 1819). 

 

Native Habitat & Geographic Range: Tropical Indian Ocean to East Africa (Kenya, Tanzania, Mozambique, Madagascar) and extending into Southeast Asian waters. They inhabit shallow intertidal and subtidal sandy or muddy seafloors, burrowing into the sediment using a muscular foot. 

Cultural & Utilitarian Uses: Large cockles in the Indo-Pacific were traditionally used as natural scrapers for preparing root vegetables (like taro and yam), shredding coconut meat, or smoothing clay vessels before firing; and water balers for canoes. 

In Europe these large cockles were often set into decorative masonry and garden grottos during 19th-century European collecting booms. 

Below-  the enormous shell Margate shell grotto in Southern England:

See https://en.wikipedia.org/wiki/Shell_Grotto,_Margate