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:
The larva lives in a case that is made of small stones, usually with pairs of larger stones on the sides; the tops of the first two thoracic segments are covered by sclerites; the top of the third thoracic segment has only a few small sclerites; the sclerotized sides of the middle thoracic segment project anteriorly beside the sclerotized first thoracic segment; anal prolegs are mostly fused with the end of the abdomen except their apical hooks.