Burrower Mayfly (Hexagenia limbata), Tehama County, California. This large mayfly is famous in some waterways for its massive emergence numbers, showing up on doppler radar and sometimes requiring snowplows to clear bridges of the spent bodies. Due to their size they are also a favorite of large trout, which can be heard slurping the mayflies from the water's surface during an emergence. It is one of the most geographically widespread mayflies in North America.