Ctenoides ales is a species of saltwater clam (family Limidae) that live in the Indo-Pacific. Also called the following: electric flame scallop, disco scallop, electric clam and disco clam.
The various names are due to the fact these clams emit light from the soft tissue parts that flashes. The light is a reflection of ambient light availbe.. either the sun or from a diver’s light. Apparently the quickness of the tissue going from white reflective tissue to the inner red tissue in response to light gives the appearance of flashing light, like a disco ball.
Ctenoides ales https://en.wikipedia.org/wiki/Ctenoides_ales
Why Do “Disco Clams” Put On Brilliant Light Shows?http://news.nationalgeographic.com/news/2015/01/150106-disco-clams-animals-science-oceans-light-predators/
Ctenoides ales http://eol.org/pages/4729743/overview
How This Mysterious Clam Puts on an Underwater Light Show https://www.wired.com/2014/06/disco-clams-light-show/