| 1a. Case coiled like a snail shell, constructed of sand grains or small rock fragments. Anal claw comb-shaped. HELICOPSYCHIDAE: Helicopsyche borealis | |
| 1b. Case straight(or almost straight) or larvae free-living, without a case. Anal claw hook-shaped. | |
| 2a. Dorsum of each thoracic segment covered by sclerites. | |
| 2b. Metanotum and sometimes mesonotum entirely membranous, or largely so and bearing several pairs of smaller sclerites. | |
| 3a. Abdomen with ventrolateral rows of branched gills; prominent brush of long hairs at base of anal claw; posteriormargin of meso and metanotal plates lobate; mature larvae large 20 mm + in length. Free living, no case, larvae construct fixed retreats under rocks. HYDROPSYCHIDAE | |
| 3b. Abdomen lackng ventrolateral gills; only one or two hairs at base of anal claw;posterior margin of meso- and metanotal plates usually straight; less than 6 mm long. Case sand, algae or silk, purse shaped. HYDROPTILIDAE | |
| 4a. Antennae very long and prominent for a caddisfly, at least 6 times as long as wide; and/or sclerites on mesonotum lightly pigmented except for as pair of dark curved lines on posterior half (Check this) Case: Sand grains or fine stones, often black LEPTOCERIDAE | |
| 4b. Antennae of normal length, no more than 3 times as long as wide, or not apparent; mesonotum never with pair of dark curved lines. | |
| 5a. Mesonotum largely or entirely membranous; or with small clerites not covering more than half the mesonotum; pronotum never with an anterolateral lobe. | |
| 5b. Mesonotum largely covered by sclerotized plates, variously subdivided and usually pigmented, although sometimes lightly; pronotum sometimes with a transverse carina terminating in prominent antero lateral lobes. | |
| 6a. Abdominal segment IX with sclerite on dorsum. | |
| 6b. Abdominal segment IX with membranous dorsum. | |
| 7a. Metanotal sa3 usually consisting of a cluster of setae arising from a small rounded sclerite; prosternal horn present. Case tubular portable case of plant materials PHRYGANIDAE | |
| 7b. Metanotal sa3 consisting of a single setae not arisiong from a sclerite; prosternal horn absent. Case Tortoise like case of stones or none, free living | |
| 8a. Basal half or anal proleg broadly joined with segement IX, anal claw with at least one dorsal accessory hook. Case Tortoise-like portable cases of small stones. GLOSSOSOMATIDAE | |
| 8b. Most of anal proleg free from segment IX, anal; claw without dorsal accessory hooks. Case None, free living RHYACOPHILIDAE | |
| 9a. Labrum membranous and T-shaped, often withdrawn from view in preserved specimens. Case Free living with sac-shaped nets of silk PHILOPOTAMIDAE | |
| 9b. Bobbies key stops here(Check this) check Herman or whatever, I expect more bugs here | |
| 10a. Abdominal segement I lacking both dorsal and lateral humps; each metanotal sa1 usually lackng entirely, or, if represented by only a single seta without a sclerite, mesonotal sclerites subdividedsimilarly to figure whatever. Case Various portable cases. BRACHYCENTRIDAE | |
| 10b. Abdominal segement I always with a lateral hump on each side although not always prominent, with or without a dorsal hump; metanotal sa1 always present, usually with a sclerite bearing several setae but with at least a single setae. Case Various portable cases | |
| 11a. Antennae close to anteroir margion of eye, median dorsal hump of segment I kacking. Case Plant materials or sand. LEPIDOSTOMATIDAE | |
| 11b. Antennae about halfway between anterior margin of head capsule and eye; median dorsal hump always present | |
| 12a. Mesonotum with notch in anteromesal edge. UENOIDAE | |
| 12b. Mesonotum with anteromesal edge straight LIMNEPHILIDAE |