The famous nocturnal Hex hatch of the Midwest (and a few other lucky locations) stirs to the surface mythically large brown trout that only touch streamers for the rest of the year.
Size - (excluding tails) - 10 mm
Status at time of photo - preserved but no discernible color change as specimen was captured only a few days earlier.
Key characters - unique pattern on dorsal head and thorax; dark medial terga stripe between two paler stripes
This species is very common in west slope north Sierra watersheds. Richard W. Baumann & Boris C. Kondratieff did a study on the same section and at the same time of year (APRIL 25-29, 2010) where this specimen was taken. No other species of Isoperla were reported from this location and quinquepunctata was very abundant. Their hatches can be very heavy some Springs.