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.
Besides tail counts there are also significant differences in wing color and markings that should be taken into account.
My invaria patterns, on the other hand, go from wet fly to floating nymph to ass down (half and half) emergers to flush emergers with trailing shuck to cripples to duns and the obligatory rusty spinners.
For this reason, I love fishing this hatch.
Comments?
The invaria, on the other hand, tend to stay in the surface struggling to get out of the shuck, and once free of it, take to the air almost immediately.