The famous nocturnal Hex hatch of the Midwest (and a few other lucky locations) stirs to the surface mythically large brown trout that only touch streamers for the rest of the year.
Subcosta: The subcosta (denoted Sc) second major longitudinal wing vein, located behind the costa. In stoneflies, it often appears to be a short (about 1/3 wing length) loop off of the third vein, the radius.
These other words reference the same concept: subcostal, subcostal vein, vein Sc, Sc.