The longfin sculpin was first formally described in 1895 by the American ichthyologist Edwin Chapin Starks with its type locality given as Point Orchard in Puget Sound near Seattle, Washington.

[5] The longfin sculpin's genus name, Jordania, honours David Starr Jordan who Starks said was his "teacher in ichthyology".

Starks did not explain his choice of specific name but in 1898 Jordan and Barton Warren Evermann suggested that it was a compound of zona, "zone" or "band", and opi, meaning "window" or "hole", an allusion to the dark bar, zona, zone (i.e., band), and opi, window (actually hole), referring to dark bar half as wide as eye, running from eye downward across cheek to anterior end of interopercle, edged on each side by a pale streak, half as broad as the eye, extending from the eye down over the cheek to forward end of interopercle.

[7] The longfin sculpin is found in the eastern North Pacific Ocean occurring from Baranof Island in southeastern Alaska to Point Lobos in central California.

[7] The longfin sculpin is adapted morphologically and behaviorally to inhabit a variety of rock surfaces and to feed on an array of prey types.