In oil and blister beetles: a larval instar which resembles a pupa in being immobile and coarctate but is followed by another (apodous) larval stage. In certain other insects (e.g. thrips, whiteflies, mealy bugs) and mites: a quiescent, non-feeding larval stage preceding the emergence of the adult. Also: an abnormal or mutant form resembling a pupa but incapable of further development.