A female
subimago of a March Brown
mayfly (
Rhithrogena germanica). Mayflies belong to the
order Ephemeroptera, and the only
insects that have a subimago phase. This stage is a favourite food of many fish, and many
fishing flies are modeled to resemble them. They are
aquatic insects whose
nymph stage usually lasts one year in
freshwater. The adults are short-lived, from as little as thirty minutes to a few days depending on the species.
Photo credit: Richard Bartz