Soft-shell clam

Soft-shell clams(American English) orSand gaper(British English/Europe),scientific nameMya arenaria, popularly called "steamers", "softshells", "piss clams", "Ipswichclams", or "Essexclams", are aspeciesof edible saltwaterclam, amarinebivalvemolluskin the familyMyidae.
These clams live buried in the sediment ontidalflats. While they are common in muddy areas, their name "arenaria" means sandy and they prefer a combination of sandy and muddy areas. They are well known as a food item on the coast ofNew Englandin the WesternAtlantic Ocean; however, the range extends much farther north to Canada and south to the Southern states. 
They are also found in the Eastern Atlantic Ocean, for example in the UK, as well as in theNorth Sea'sWadden Sea(where they are the dominant large clam).
This species has becomeinvasiveon thePacific CoastofNorth America, includingAlaska, Canada and the continental United States.HoweverM. arenariaoriginated in thePacific Oceanduring theMiocene.  It extended its range in the earlyPlioceneto the Atlantic, including European waters.  The Pacific and European populations became extinct some time in the earlyPleistocene, leaving only the Northwest Atlantic population, which subsequently spread via humans to its current distribution.It also occurs in the Mediterranean Sea.
Mya arenariahas acalcium carbonateshellthat is thin and easily broken, hence the name "soft-shells" (as opposed to its beach-dwelling neighbors in some regions, the thick-shelledquahog).
This clam is found living approximately 3–8 in (7.6–20.3 cm) under the surface of the mud. It extends its pairedsiphonsup to the surface; these draw in seawater, filter it for food, and expel it. The holes in the mud through which the water is drawn in and out can often be seen at low tide. Water may be visibly ejected from the siphon tips when pressure is applied to the surrounding mud. This makes the clams easier to locate when humans areclam digging.
As well as being eaten by humans, the soft-shelled clam is relished bysea ottersin the easternPacific Ocean,where the clam is an invasive species. In New England the soft-shell clam is preyed heavily upon bynorthern moon snailsand invasivegreen crabs. They are also a favorite of gulls, which pull the clam from the sand, climb to about 15–20 ft (5–6 m), and then drop the clam on a hard surface, breaking the shell. They then dive down quickly to eat the soft parts of the clam before others can get to it.
Soft-shell clams are edible and can be used in a variety of dishes. Before cooking, it is generally recommended that clams be stored insaltwaterfor a few hours to facilitate the expulsion of sand from their digestive tracts. Some recommend thatcornmealbe added to the water to give the clams something to filter from it.
Soft-shell clams can be eaten steamed,fried, or inclam chowder. "Steamers" (steamed soft-shell clams) are an integral part of theNew England clam bake, where they are served steamed whole in the shell, then pulled from the shell at the table, the neck skin is removed and then while holding the clam by the neck it is dipped, first in theclam brothin which they were cooked, to rinse away remaining sand, and then very briefly in meltedbutter.