Post-embryonic development of Megalolaelaps colossus sp. nov., is described and illustrated. This unusually large species of mite is closely associated with the dung beetle Oxysternon conspicillatum (Weber) (Coleoptera: Scarabaeidae) in Colombia. All instars of the mite occur on the beetle, except for the larva. This is the first description of all instars for a species in this genus.
