Genus Pycnopsyche

Pycnopsyche Banks 1905

17 species in North America listed at nearctica.com

adult length about 20 mm (head to wingtip, at rest)

Adult: body and forewing uniformly reddish-brown except for dark gray blotch near middle of wing, an irregular crescent-shaped patch distal to the blotch, and a dark band along lower half of outer margin; forewing outer margin pointed, somewhat V-shaped; antennae thick, slightly shorter than length of forewing

Larva: body yellow with unbranched abdominal gills; third thoracic segment has narrowly separated sclerites; final-instar larvae of some species such as P. guttifer construct cases of woody materials; other species construct cases from small pebbles; early instars of all species generally use plant materials for case construction

North America east of the Rockies, except the southwest and arctic; also occurs in Washington state (see distribution map of P. guttifer)

larvae develop in streams and small rivers in forested areas; adults rest on nearby vegetation during day, becoming active at night, and are attracted to light

adults fly in September and October

larvae process autumn-shed leaves; bacteria and fungi colonize the decaying leaves, providing a nutritious food source

in fall, females land on shoreline objects, then crawl underwater to lay eggs, which hatch in a few days; larvae feed on decaying leaves throughout fall and winter; in spring and early summer, final instar larvae enter pre-pupal period of quiescence (diapause) lasting from 1 to 6 months, during which they either attach their cases to the undersides of rocks, or bury themselves in gravel of streambed; pupation occurs from mid-summer to early fall; pupae crawl out of water onto shore, where adults emerge; one generation per year

(1) [has illustration of adult Pycnopsyche species]

Pobst, Dick. and Carl Richards. 1998. The Caddisfly Handbook: An Orvis Streamside Guide. Lyons Press. 160 pp. - see amazon.ca [has illustration of adult Pycnopsyche guttifer]

live adult image of P. guttifer (Thomas Ames, New Hampshire)

larva images plus habitat, food, seasonality, biology (Wilfred Laurier U., Ontario)

larva and larval case images (Valley City State U., North Dakota)

photo of larval case (U. of Massachusetts)

habits and biology (Jason Neuswanger, troutnut.com)

distribution map of P. guttifer (Pennsylvania Aquatic Flies, Penn State U.)

list of species in Great Smoky Mountains National Park (courtesy U. of Georgia)

list of species in Michigan (Ethan Bright, U. of Michigan)