Their head capsule is well developed dorsally, and they have long abdominal prolegs with crocheted hooks.

These structures help the larvae move without being washed away in their preferred larval habitat, fast-flowing montane streams and torrents.

Adults have stout, tapered abdomens, slightly elongated legs, with aristate antennae.

Adult athericids usually rest on the upper surface of leaves, near the streams from which they emerge, or more inland if they are looking for a blood meal.

Athericids commonly stroke or palpate the surface of leaves, an action they share with the Tabanidae.