All post-embryonic instars lack the third and fourth pairs of legs, and the respiratory system is also absent.

The body shape is usually long and wormlike (vermiform), but it can rarely be flattened or lobulate.

The posterior part of the body is annulate, meaning it is covered in rings (annuli).

The superfamily includes many important crop pests, some of which transmit plant diseases.

Forms with two pairs of legs, already similar to the modern ones, have been found in Triassic amber from Italy: Ampezzoa, Triasacarus,[5] Minyacarus and Cheirolepidoptus, which were specialised on extinct conifers of family Cheirolepidiaceae.

The four genera were subsequently placed in a new extinct clade, the Triasacaroidea, which is the sister group to the extant Eriophyoidea.