Moved from Mayflies.

I've tried to take this one beyond family several times, but I just can't see a way to do that. The contiguous eyes would seem to suggest either Epeorus or Rithrogena. However, most Epeorus have a spot on the middle of each femur (at least, that is true for the Eastern species), and Rithrogena are usually darker (more brownish). Less common genera like Ironodes and Nixe might also be possibilities, but they don't seem to be listed for MT.