The northern lampfish (Stenobrachius leucopsarus), also known as smallfin lanternfish,[1] is a small oceanic fish in the family Myctophidae.

First described by husband and wife ichthyologists Carl H. and Rosa Smith Eigenmann in 1890,[2] it is named for the numerous small round photophores that line the ventral surface of its head and body.

A blunt-nosed, relatively large-mouthed fish with small teeth and large eyes,[3] it is gray to dark greenish blue on its dorsal surface and paler ventrally, with black on its fins and operculum.

[3] Adults can reach 13 centimetres (5 in) in length[3] and live as long as 8 years.

[2] Found in the Pacific Ocean from Japan and Baja California to the Bering Sea,[3] it is the most common species of lanternfish in the northwestern Pacific,[4] and one of the most abundant larval fish in the California Current.