Moved from Callibaetis.

This is probably C. ferrugineus ferrugineus.

This is a female Callibaetis imago. On some waters, mayflies (especially baetids) can be found nearly year-round, but the greatest numbers and variety of species are usually found in May and June in the Northeast. Callibaetis mayflies are often multi-brooded (more than one generation per year in all but the coldest climes). They are typically pond and lake dwellers, although populations are also found in the slower sections of some streams and rivers.