Ryan Photographic - Limidae - File shells
The family Limidae contains around 130 species in 10 genera. They are all marine and found in most of the world's oceans. All the websites I accessed basically plagiarized each other saying that many members of the family can swim by waving their long mantle tentacles. This is a behavior I haven't seen and it seems more likely they would swim by "clapping" their shell valves like scallops. But what is fascinating - and none of the sites I accessed followed up on this - "many species build byssal nests for protection". Byssal threads are strong protein fibers produced by mussels and other bivalve molluscs to keep themselves attached to the substrate. The idea of a byssal "nest" intrigues me and makes these fascinating animals even more interesting.
Ctenoides ales Electric clam
Ctenoides ales Electric clam, Raja Ampat, West Papua IMG_1945
Ctenoides ales Electric file clam 2, Kri Eco, Raja Ampat
Click here for a video of an electric clam doing its thing.