Stenacron interpunctatum (inter punk tate um) heterotarsale nymphs live under and around the stones of fast to medium moving riffles, they can also be found under rocks in medium to slow moving riffles prior to emerging. Stenacron heterotarsale never hatch in large numbers. Hatching mainly in the evening, but like other Stenacron will hatch sporadically through out the day on cloudy cool days. Male duns are light to pale yellow in color with pale yellowish wings, females are yellowish orange with bright yellow wings. Many anglers confuse the female for the much larger Anthopotamus.