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.
Preferred waters: Slow, alkaline streams and lakes
In 215 records from GBIF, adults of this genus have mostly been collected during June (46%), July (27%), May (12%), and August (12%).
In 361 records from GBIF, this genus has been collected at elevations ranging from -30 to 11444 ft, with an average (median) of 804 ft.
They then emerge by swimming toward the surface and immediately taking flight. They pop through the surface film like miniature helicopters rising toward the open sky. We believe that molting takes place either very quickly or when the duns are high in the trees, for try as we might, we almost never can find a dun (day or night) despite the fact that we can locate hundreds of spinners.
Time of day: Usually dusk in the East and Midwest, morning in the West, sometimes afternoon in cold weather
Current speed: Slow
Substrate: Silt, vegetation