Electric fileclam
Ctenoides ales
About
The electric fileclam is a saltwater clam known for the flashing light display along the edge of its mantle. Its nicknames, such as disco clam, come from this flashing, which looks like a disco ball.
Also known as: ctenoides ales, electric file clam, electric flame scallop, disco clam, disco scallop, electric clam
- Depth
- 5–20 m
How to tell it apart
Look for a clam with a red mantle edge that seems to flash with white light, like a disco ball.
Appearance
The outer edge of its mantle has highly reflective white tissue next to red tissue; by exposing and hiding the reflective edge very quickly, the clam appears to flash.
Habitat
It lives in tropical waters of the central Indo-Pacific, from Indonesia to Palau and New Caledonia, usually at 5 to 20 m.
Behaviour
The flashing is not bioluminescence: the reflective mantle edge reflects ambient light from the sun or a dive light. A 2016 study suggested the flashing most likely evolved to deter predators.
Did you know?
The reflective edge of its mantle contains tiny spheres of silica, which make it so bright.
Log it in Into the Blue
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