[4][5] It was described by David Starr Jordan and John Otterbein Snyder in 1901, originally under the genus Leptocephalus.

[7] G. nystromi nystromi is a tropical, marine eel which is known from the western Pacific Ocean, including Japan, the South China Sea, and Hawaii.

It dwells at a depth range of 250–355 meters, and inhabits reefs.

[5] G. nystromi ginanago is a marine, temperate water-dwelling eel which is known from Japan, in the northwestern Pacific Ocean.

Males can reach a maximum total length of 40 centimeters.