Bathylychnops exilis, the Javelin spookfish, is a species of barreleye found in the northern Pacific and in the eastern Atlantic Ocean near the Azores where it is found at depths of around 640 metres (2,100 ft).
This species grows to a length of 50 centimetres (20 in) SL.
[2] The species is notable for unusual protuberances that grow from its eyes, which each have "a well developed lens"[3] and a retina, and which have led to the species being called a "four-eyed" fish.
[5] The Javelin spookfish have a distinct and advantageous secondary globe to their eyes.
This feature provides great benefits in their chances for survival.