This is the most poorly understood and yet in some ways the most distinctive of the four accepted varieties of Castilleja minor. With its obtuse to rounded bract tips, bright-red, upcurved lower corolla lip, and relatively long corolla beak, it is easily distinguished from the other varieties. Despite this unique combination of characters, var. spiralis was lumped with var. stenantha (long known as Castilleja stenantha) in the Jepson Manual as a single entity, subsp. spiralis. A comparison of these plants with my photos of var. stenantha should make clear the easily-recognized differences between these forms.
Var. spiralis occurs mostly in moist riparian areas along streams and creeks in highly serpentine regions in hilly country in central California, from the western foothills of the Sierra Nevada westward. It overlaps somewhat with the range of var. stenantha, but within populations there is little or no overlap in the distinguishing characters.