domatium

1. (entomology, botany) A chamber produced by a plant in which insects, mites, or fungi live.Examples: "A domatium typically takes the form of a hollow under a leaf, or a system of tunnels in a thorn or stem. Ideally, it is a mutualistic adaptation and should not be confused with simple damage by a borer or gall-forming pest, although commonly there is no sharp distinction between domatia of value to the plant and galls caused by harmful aphids and mites, for example."; "All are ordinary anatomical features of the plants that the ants exploit, apparently in a unilateral manner. In contrast, the domatia listed comprehensively in Table 14-1 do appear uniquely to serve as ant nests."; "Although the earliest work on mites and leaf domatia was inspired by a belief that mites protected trees from fungal disease (O'Dowd and Willson 1989), mite–fungus–plant interactions received experimental attention only recently."