The other genus of Large Winter stonefly I have seen in our streams -- at least to date, I have only seen two -- is Strophopteryx (on the genus Taeniopteryx, see the entry for December 16). Strophopteryx nymphs appear later than Taeniopteryx nymphs: my first sighting last year was on December 28, this year I found them as early as December the 8th. In December the nymphs are still very small; fully mature nymphs can be found from late January into March (by February, most Taeniopteryx nymphs have hatched).
Oh, one more thing. When Strophopteryx nymphs are preserved in alcohol, they always -- well, almost always at least -- curl up in the shape of a "C" as in the second photo above.