Colored Scanning Electron Micrograph of a Box mite (Oribatidae: Atropacarus sp.).
Adult Box mites are slow-moving, deliberate, and heavily encumbered in armour. One remarkable type of defence that has evolved at least three times in the Oribatida is called ptychoidy (more Greek, ‘ptych’, a fold). Ptychoid mites are able to fold their legs into their bodies and close the anterior shell-like aspis over the legs, giving rise to a less English-tongue-twisting name, ‘box mites’. Most Boxmite species feature a clean body but some cover themselves with a layer of soil. Presumably this serves as a visual or, more likely, tactile camouflage that increases the chance a predator will move on (‘get along now, nothing but a bit of dirt, your dinner is elsewhere’).