Protura (see drawing of a typical one below) are minute and delicate, ranging in size from 0.2 - 2.6mm long, colourless and eyeless. They do not have antennae or any terminal filaments, e. g. cerci. They have a cone-shaped head, the abdomen has twelve segments, and legs five segments. They are the only insects that have no antennae and hold their first pair of legs in front of their head using them like antennae.
There are about 750 species worldwide, 175 European, and 15 British species. They are most easily found in summer.
Protura are found in damp soil, moss and leaf litter where they feed on decayed organic matter. In the U. K. species fungal mycelium seems to be the main food.
Male protura do not produce spermatophores, so it is believed that sperm transfer is direct. This lack of knowledge highlights how little we know of these insects.
When the larvae first hatch from the egg they have just 9 abdominal segments; this increases to the 12 of an adult with each moult.
It is thought that the Protura may be descended from the Diplura.