Mark Melton
Active Member
This species shows up as larvae and pupae on large cobbles in moderate flows. The adult shows up as a terrestrial moth which lays it's eggs in the water. The larvae and pupae are camouflaged underneath mats on top of and on the sides of cobbles. They're found in the summer months in the Russian River. Mature larvae measure about 9-10 mm and pupae about 9 mm.
Here is an article on fishing them; https://cpw.state.co.us/Documents/LandWater/Riverwatch/EntomologyContents/AquaticMoths.pdf
And another on a wasp that parasitizes them; https://ia800205.us.archive.org/14/items/biostor-76932/biostor-76932.pdf
Larvae with mat
Larvae
Ventral view of larvae
Mat that hides pupae
Immature pupae
Mature pupae
Here is an article on fishing them; https://cpw.state.co.us/Documents/LandWater/Riverwatch/EntomologyContents/AquaticMoths.pdf
And another on a wasp that parasitizes them; https://ia800205.us.archive.org/14/items/biostor-76932/biostor-76932.pdf

Larvae with mat

Larvae

Ventral view of larvae

Mat that hides pupae

Immature pupae

Mature pupae