ABSTRACT
A. N. Lundstrom introduced the term domatium for a nonpathological plant structure that harbors other organisms beneficial to plants, and in contrast to structures such as galls that contain organisms harmful to plants. Lundström termed the domatia on plant leaves that he observed frequented by mites acarodomatia or mite domatia. The term domatium has also been applied to various plant cavities used by ants as nest sites. The mite-domatia interaction may function as a facultative mutualism in which domatia serves as shelters and nurseries for mites that reduce the number of phytophagous arthropods and pathogens on domatia-bearing plants. The results of studies provide correlative support for the plant protection-mutualism hypothesis: Potentially beneficial mites are strongly associated with domatia, and predaceous mites preferentially oviposit within domatia. The evolution and maintenance of a mite-domatia mutualism requires that domatia-associated mites and domatia-bearing plants experience enhanced fitness through benefits from this interaction that result in increased reproduction.
