Water mites of the genus
Arrenurus develop through seven stages - egg, inactive prelarva, larva, protonymph, deutonymph, tritonymph, and adult. Only the larva is parasitic.
Arrenurus larvae are ectoparasites of freshwater aquatic insects, particularly the
Odonata.
Class: Arachnida
Subclass: Acari
Order: Trombidiformes
Family: Arrenuridae