Scopelarchidae

Scopelarchidae is a family of deep-sea fish, commonly known as the **pearleye family**. These fish are found in temperate and tropical oceans worldwide, typically inhabiting depths between 500 and 1,500 meters. They are characterized by their large eyes, which are oriented upwards and have a reflective tapetum lucidum, allowing them to detect faint bioluminescent light from prey above.

Pearleyes are relatively small, slender fish, usually measuring less than 20 centimeters in length. They possess a single, long dorsal fin and an anal fin that is nearly as long. Their coloration is often silvery or dark, providing camouflage in the dim light of the mesopelagic zone. The family contains several genera, including Scopelarchus, Bentheuphausia, and Rosenblattichthys, with a number of distinct species.

Little is known about the reproductive habits or specific diets of most pearleye species due to their deep-sea habitat. However, their upward-facing eyes suggest they are ambush predators, feeding on small crustaceans and other planktonic organisms that drift down from shallower waters. They are not commercially important and are rarely encountered by humans.