Bathylychnops exilis

Bathylychnops exilis

Bathylychnops exilis is a Tiefseefischart from the family of ghosts fish ( Opisthoproctidae ). She lives in the Atlantic Ocean, north of the Azores and in the northern Pacific Ocean along the coasts of British Columbia and California, Japan and in the northern mid- Pacific. The pelagic fish live in the mesopelagic in depths of 100 to 1000 meters. Also eggs and larvae are pelagic.

Features

With a maximum length of 50 cm Bathylychnops exilis is the largest representative of ghosts fish. His body is transparent and pike -like elongated dorsal and anal fin sit far back. These are supported 13-16 Dorsal soft rays and 10-14 anal soft rays. The number of vertebrae is 78 to 84, the second of Branchiostegalstrahlen The muscles of Bathylychnops exilis is well developed and can be an active swimmer suspect, while most other deep-sea fish are sluggish.

Eye

Noteworthy are that closely related, large eyes of Bathylychnops exilis, which reach a diameter of 3% of the body length and are fitted in the bottom half with a strange, spherical outgrowth. Originally, these excesses were for light organs ( from where the name comes from: βαθύ " deep " (Deep Sea ), " lantern" λύχνος, ὄψ "eye"; exilis " lean" ) held until one has found a lens and a retina in them. To form the excesses downward additional eyes and probably serve to perceive predators coming from the depths that could be a threat to the fish. The main eyes are directed upwards and probably allow stereoscopic vision. The lenses of the eyes to achieve the addition of half the diameter of the main focus lens. The retina of the supplementary eye has grown at the bottom of the main retina. There is only one optic nerve.