Major Body Regions

Insects, springtails and other hexapods (as well as 1st instar millipedes) have three body regions: a head with antennae and often eyes, a thorax with three pairs of legs and up to two pairs of wings, and an abdomen that has no true legs (styli or prolegs may be present - see Character 6d) and is usually clearly segmented.

 

Allow misinterpretations.  Mite larvae are hexapod and could be misinterpreted as having a thorax.