The larvae of Rhyacophilidae exhibit a variety of feeding strategies as young instars, feeding as collector-gatherers, scaper-grazers, or shredder-herbivores, but mature larvae are mainly free-ranging, engulfing predators. Larvae are free-living, meaning that they do not live in a case or retreat, but simply move throughout the environment, clinging to the substrate and chasing prey. Before pupation, a rock shelter is built and a semipermeable cocoon is spun inside. Larvae are often green in color, and often have well-defined segments, giving the body a beaded appearance.
Upper Midwest: up to 0
Southeast: up to 0
Engulfer / Predator
+ Expanded Character List
Order: Larvae: Wings/wing pads absent. Eye spots present, but compound eyes absent. Antennae usually small, inconspicuous. Three pairs of segmented legs present on thorax. Pair of anal prolegs, each with single hook, located on last abdominal segment. Larvae can be free-living, in silken retreats attached to substrate, or in usually-portable tubes or cases made of sand, rocks, or plant material.
Family: Antenna small and inconspicuous. Pronotum without lobes in anterior corners. Meso- and metanota membranous. Metanotum with lateral setal areas (sa3) each with only a single seta, with or without a sclerite. Abdominal tergum IX with a sclerite, sometimes inconspicuous or retracted under intersegmental fold of abdominal tergum VIII. Anal prolegs free, not closely fused to segment IX. Anal claw without dorsal accessory hook; however, sometimes with a secondary lateral claw and sometimes with ventral teeth. Larvae are free-living until pupation.