Greenwells glory is just one common name used to describe some, but not all, members of the insect family groups called Baetis (pronounced beet-us) Ephemerella, Baetidae, Drunella and Diphetor. Other names include Bluewing, Tiny Olives, Iron Blue Dun, Iron Blue Quill, Little Slate Winged Olive, Little Slate Winged brown quill, Tiny Western Olive and Little Western Iron Blue Quill. There are many species of Blue Winged Olive mayflies. There are 153 species currently listed for North America. There is often confusion among fly fishermen because the species are difficult to distinguish