Coloburiscus mayfly nymphs are easily distinguished by the cactus-like gills covering the top of the abdomen. The front and mid legs are very hairy.
Coloburiscus larvae are most abundant in stony or gravelly, cold water, well aerated, bush covered streams.
They are filter feeders, using their hairy legs to trap drifting food particles (probably both plant fragments and small invertebrates).
High abundances of Coloburiscus are indicative of good habitat and water quality, particularly if other mayflies or stoneflies are common or abundant. They have tolerance values of 9 (hard bottom sites) and 8.1 (soft bottom sites).