Siphlonurus quebecensis (Gray Drake) Mayfly NymphView 5 PicturesI photographed this nymph in the middle of molting between one instar (Instar: Many invertebrates molt through dozens of progressively larger and better-developed stages as they grow. Each of these stages is known as an instar. Hard-bodied nymphs typically molt through more instars than soft-bodied larvae.) and the next (not hatching).
Siphlonurus phyllis (Gray Drake) Mayfly NymphView 3 PicturesThis specimen was the first record from Montana and the first record from the mountain west except Alberta where it was first described. It was found in temporary ponds.The nymph has double gills on all segments. The abdominal stripe is an important feature for identification