The Nemouridae are a family of stoneflies containing more than 700 described species, occurring primarily in the Holarctic region.
Fly fishermen often refer to these insects as tiny winter blacks.
Although these insects use a wide range of flowing-water habitats, they tend to be most prevalent in smaller streams.
The nymphs are distinctive, being broad-bodied and bristly with divergent wing pads.
The Plecoptera species file lists:[2][3] Authority: Baumann, 1975 Authority: Billberg, 1820