Microdon

Definition

A genus of hover flies (Diptera: Syrphidae) whose larvae are obligate myrmecophiles, developing within the nests of ants where they feed on ant brood or detritus. Adults are typically small, robust, and inconspicuous, often mimicking stinging Hymenoptera or appearing wasp-like. The genus is taxonomically challenging due to larval adaptations that obscure typical syrphid morphology and the scarcity of adult specimens.

Etymology

From Greek mikros (small) + odous (tooth), referring to the reduced mouthpart structures characteristic of the genus.

Example

Microdon mutabilis larvae live as social parasites in Formica ant nests, where they are fed by worker ants and can remain undetected for years due to their chemically camouflaged, legless, slug-like appearance.

Related Terms

• myrmecophile
• Syrphidae
• social parasitism
• mimicry
• inquiline

Usage Notes

Microdon is a homonym across multiple kingdoms: the dipteran genus (Meigen, 1803) is the primary usage in entomology, but the name also applies to a plant genus (Scrophulariaceae), an extinct amphibian genus (Micromelerpetontidae), a bivalve genus (Venerida), and a fish genus (Pycnodontidae). In entomological contexts, always specify Microdon Meigen, 1803 to avoid ambiguity. The larval stage is so morphologically divergent—lacking the typical maggot form and possessing a tough, segmented integument—that early naturalists misidentified Microdon larvae as mollusks or scale insects.