Springtails are very small and primitive insects. They even belong to a subclass of the insects, along with among others the Silverfish and Coneheads: the Apterygota (=wingless). Within this group not even the adults ever have wings. And even though they do change skin from time to time they do not change the way they look. The larvae are just smaller images of the adults. These animals all have wires on the tail (the so-called cerci). Usually they have two, but silverfish for instance have three. They are hard to see in Springtails, for they have the wires folded under their bodies. They are used to jump with, hence the name of the group.
Springtails are never big. The giants may reach some 10 mm, many even remain below the size of 1 mm. Another characteristics of these wingless insects is the fact that they have single eyes and very few body segments. They feed on rotting organic materials and fungi. They are present in great numbers, but because of their size are hardly ever noticed. Entomobrya nivalis is a moss dwelling creature.