Domatium

A domatium (plural: domatia, from the Latin "domus", meaning home) is a tiny chamber that houses arthropods, produced by a plant.

Most domatia are inhabited either by mites or ants, in what can be a mutualist relationship, but other arthropods such as thrips may take parasitic advantage of the protection offered by this structure.

The variety of the plants that provide myrmecodomatia, and the ranges of forms of such domatia are considerable.

Often domatia are formed on the lower surface of leaves, at the juncture of the midrib and the veins.

Domatia are also found in some rainforest tree species in the families Alangiaceae, Elaeocarpaceae, Fabaceae, Icacinaceae, Meliaceae, Rubiaceae, Sapindaceae and Simaroubaceae.

A hairless foveole domatium in the leaf underside of Guioa acutifolia
Mite inside domatium of Cinnamomum camphora