Leptophlebia nymphs live in very slow to dead water where the substrate consists of silt, dead vegetation, and sticks. Like subvaria nymphs they spend a fair amount of time drifting near the waters surface, or in the surface film itself as they shed their husk. This is a common similarity im most early season hatches due to the cold weather temperatures, giving the angler a oportunity to fish an emerger pattern effectively. Duns are very dark in color with dark dun wings and dark olive brown bodies. Leptophlebia hatch early in the season overlaping Epeorus pleuralis, and Ephemerella subvaria. Don't mistake it for a large dark colored Quill Gordon.