are lampriform fishes
in the family Lophotidae
. They are elongate ribbon-like fishes, silver in color, found in deep tropical and subtropical waters worldwide. Their scientific name is from Greek lophos
meaning "crest" and refer to the crest (part of the dorsal fin
) that emerges from the snout and head; this structure gives them their other name of unicorn fishes
They possess ink sacs that open into their cloaca from which they can produce a cloud of black ink when threatened (as in many cephalopods).
There are three species in two genera: