Finally!!! I now know what those strange shells are called. In the northern central regions, they're called balay shells; or ugpan further to the south. The tindera (sales lady) said that in English, they called it tongue clam or shell, due to the long white "tongue".
still, I also know how to cook it and eat it! Apparently, they're good simply
sauteed in ginger, garlic, onions and tomatoes.
unlike mussels or
clams, they don't open when they're cooked, in fact, a little effort is required to open the shells. The shell meat is rather small and a bit rubbery, with a taste
reminiscent of oysters, but the best part, apparently, is the "tongue"
contains a tasty treat that needs to be coaxed out.
an interesting shell, not bad tasting but I still prefer
oysters, first and foremost, followed closely by tahong, then halaan!