---

Parydra coarctata has fork of R2+3 not darkened, size 4 mm.

Parydra littoralis has fork 2+3 darkened, cheeks high (eye-to-cheek ratio about 2:1, see lateral view), size 4.5-5 mm

Parydra quadripunctata has fork R2+3 darkened, cheeks low (ratio 4:1, size 3.5-4 mm.:)