Definition of Tripod fish

The tripod fish, Bathypterois grallator, is an unusual bathypelagic (deep sea) fish and is named for the long extensions of its pelvic and lower caudal fins, on which it stands on the sea floor. The tripod fish is closely related to the smaller spiderfish (Bathypterois longifilis), which is similar in appearance and habits but smaller and with much shorter fin extensions; the two species are often found standing very near to one another on the ocean floor.