One of 11 Nearctic species in the genus.
In the genus Stylurus (the Hanging Clubtails) this is the only North American species with adbominal segment 9 noticeably longer than abdominal segement 8. The last two segments (s9 and s10) are dark on the dorsal surface.
Northeast United States (just barely edging into Canada); as far South as Kentucky and Tennessee.
Small to medium-sized rivers with mud or sand bottoms.
Mid-June through much of October.