Old Hickory - Bug Question

[bd]

Does anyone have an ID for the big mayflies that are hatching just before dark on Old Hickory right now?  There seem to be bunches of them just hovering in the air at the edge of the water just before dark.  They're light yellowish, and very different from the big brown "willow flies" that will hatch later in the year around June or July.  I wasn't able to get a pic of them, but if anyone knows what I'm talking about, any info would be appreciated.

bd

[MikeA]

Hexagenia limbata maybe?



Although the dun may appear at first to be an adult mayfly, it is not fully developed sexually, and its color is usually opaque than the adult. During the night or the following day, male and female duns molt a final time, leaving behind a subimaginal exoskeleton. They are now sexually mature imagoes or (spinners - adults). Neither the duns nor spinners eat, because their mouthparts are not completely developed. At dusk or at night, female spinners fly into a large swarm of male spinners. The males and females mate in flight during darkness. Within minutes of mating, the female spinner settles down to the lake surface, extrudes her eggs, and dies.   This is called a spinner fall.

Here is an article you might find useful.
http://www.flyfishusa.com/flies/the-hex-hatch-2.html

[bd]

Thanks, Mike.  It could have been a hex dun.  If I could ever remember to take a camera when I fish, maybe I could get a pic.

bd