Stoneflies belonging to the Genus Pteronarcys (Salmonflies) are easily recognized by their large size. These long slender black stonefly nymphs can reach lengths that often exceed 5cm. After four years in the river the nymphs will crawl to shore to hatch, usually from May to June. The adults are equally as large and have a distinct pink/salmon colour on the ventral side of their abdomen, hence the name Salmonfly.
There are probably dozens of patterns available that imitate these giants of the aquatic insect world. Below is my version on this theme. The recipe for the Blackstone is very similar to the Gingerstone recipe, but with a black theme.
Originator: Danie Erasmus
Hook: #6 or #8 TMC 200R BL
Thread: 6/0 Black
Head: 3/16 black tungsten bead for the #6 hook, 5/32 for a size 8
Overbody: Black dubbing
Underbody: 0.02 lead wire
Ribbing: Medium copper wire
Wingcase: 1⁄4” tan scud back such as those made by Hareline Dubbing Inc
Legs: Black Stretch Flexx by Uni
Tail: Black goose biots