Written By - Troutnut - 05/23/2007
Link to Original Article here

Most fly anglers know that mayflies have two adult stages: duns and spinners. Entomologists call them subimagos and imagos. See the main Ephemeroptera page for the basics of these two stages.

Much of angling literature and this website consists of tips about matching one stage or the other for the various species. In May of 2005 I caught one mayfly molting between the two stages.

It belongs to the species Leptophlebia cupida, which anglers know as the Black Quill.