(In the photo above -- the common stonefly (Perlid) Claasenia sabulosa found last year in Rock Creek near Missoula, Montana. This is a species that does not occur in the East.)
Photos I've taken of the stonefly species we find in our streams will be presented in three entries: 1) Common Stoneflies (Perlidae); 2) Perlodid stoneflies (Perlodidae); and 3) all other stoneflies.
II. Plecoptera (Stoneflies)
Perlidae (Common Stoneflies)
1. Acroneuria abnormis. Size: male nymphs 15-20 mm, female nymphs 25-30 mm. Season: All Year, Mature in Late Spring and Early Summer.
2. Acroneuria arenosa (possibly A. evoluta)
4. Acroneuria sp. (possibly internata, possibly abnormis)
5. Acroneuria lycorias
6. Agnetina annulipes. Size: not given by Beaty, young one below is 10 mm; Season: Immature in Late Summer, Mature in Late Spring.
7. Agnetina flavescens. Size: not given by Beaty: Spring and Summer.
8. Agnetina capitata
9. Eccoptura xanthenses. Size: 15-22 mm; Season: All Year, Mature in Late Spring, Early Summer.
10. Neoperla. Size: 7-12 mm; Season: Immature in Spring, Mature in Summer (Univoltine).
11. Paragnetina immarginata. Size: not given by Beaty (but big); Season: Immature in Late Summer, Mature in Late Spring and Early Summer.
12. Paragnetina fumosa. Size 10 mm; Season: Spring through Early Winter.
13. Perlesta. Size: 8-12 mm; Season: Immature in Early Spring, Mature in Early Summer.
14. The common stone in the photo below is a Paragnetina media. This species does occur in our area, but to date, I haven't found one: thus, it is not yet in my "list". I found this one in June in Roaring Creek in Central PA.