[5] The headlight fish was first described by American ichthyologists George Brown Goode and Tarleton Hoffman Bean in 1896.

[7] The generic name, Diaphus, is a combination of the Greek words Dia (Δία), meaning "through", and Physa (Φυσα), "bellows".

In the eastern Atlantic, they are known from the Antarctic Convergence zone in the south to the English Channel in the north.

[9] In the western Atlantic, they can be found from the east coast of the United States south to the southern border of Brazil.

There is some size stratification with depth, and the female fish are believed to spawn in deep water.