Bearded Netdevil (Linophryne sp.) from the Gulf of Mexico, between 1,200 and 1,500 meters depth.

This is a female anglerfish from the family Linophrynidae and the genus Linophryne, known as the “Netdevils” or "Bearded Seadevils." Linophryne is a special group of fish because they demonstrate two distinctive modes of bioluminescence, intrinsic bioluminescence and bacterial bioluminescence. The evolution of both modes in a single species is extremely rare. The esca or “lure” is filled with bacteria that produce light and live in a symbiosis with the fish (close-up of esca to the upper right, the image is a composite). The chin barbel or “beard” glows in the dark via the production of luciferin and luciferase by the fish – an intrinsic method of light production by the fish itself (close up to the lower right - image is a composite). This specimen was trawled up in the Gulf of Mexico, 2016, from between 1,200 and 1,500 meters depth. Image courtesy of the DEEPEND project.