Psilidae

Psilidae is a small family of true flies (Diptera) commonly known as rust flies or psiliid flies. The group has a worldwide distribution, with the highest diversity in temperate regions. They are typically found in habitats rich in decaying organic matter, such as dung, compost, leaf litter, and moldy vegetation.

Adults are small to medium in size and usually have a slender body with long legs. They resemble other small nematoceran flies, and precise identification often relies on subtle features of wing venation and antennae, sometimes requiring examination of male genitalia for species-level separation.

The life cycle includes eggs laid in or on decaying organic material. Larvae are generally saprophagous, developing in dung, rotting plant matter, or soil enriched with organic material. Some species may have larvae associated with plant roots, including grasses, but such cases are less common. Pupation occurs in the larval habitat, with the pupa remaining in the surrounding substrate until emergence.

Ecology and significance: Psilidae are not considered major agricultural pests. They are primarily of interest to taxonomists, ecologists, and biodiversity researchers studying decomposer communities and Diptera diversity. The family contains several genera and many described species, distributed across multiple continents.