Postimaginal-molting
Guides
Opilioacarida
Opilioacarida is a small order of mites containing a single family, Opilioacaridae, with approximately 13 genera and 53 valid taxa. These mites are among the largest of their kind (1.5–2.5 mm) and are considered primitive due to retained ancestral traits including six pairs of eyes and abdominal segmentation. Molecular phylogenetics places them within Parasitiformes, though historically they were treated as distinct from both Acariformes and Parasitiformes. The group has a worldwide distribution with notable diversity in the Americas.
Opilioacaridae
Opilioacarid mites, Primitive mites
Opilioacaridae is the sole family in the order Opilioacarida, comprising approximately 13 genera of rare, relatively large mites (1.5–2.5 mm). These mites are considered primitive due to retention of six pairs of eyes and abdominal segmentation, traits lost in other mite lineages. Historically treated as distinct from both Acariformes and Parasitiformes, molecular phylogenetics now places them within Parasitiformes. The family exhibits a disjunct global distribution with populations in semi-arid and tropical regions, including caves, leaf-litter, and rock habitats.