Opilioacarida
Opilioacarida is an order of small arachnids, typically measuring 1-2 millimeters in length. They are characterized by their elongated bodies and legs, which are covered in short setae. Opilioacaridans have two pairs of eyes, located on the dorsal surface of the prosoma. The order is divided into three families: Opilioacaridae, NeoCaridae, and Pachyolpiidae. These arachnids are found worldwide, particularly in humid environments such as leaf litter and soil. They are believed to be predators, feeding on small insects and other arthropods. Despite their similar appearance to opiliones (harvestmen), opilioacaridans are not closely related to them and are classified in a separate subclass, the Acari.