Platygastridae

Definition

A family of minute parasitoid wasps (Hymenoptera: Platygastroidea) characterized by their diminutive size (typically 1–2 mm), compact black and shining bodies, geniculate antennae with an eight-segmented flagellum, and wings that often lack visible venation. Members are exclusively parasitoids of insect eggs, particularly those of gall midges (Cecidomyiidae) and other small Diptera, making them significant biological control agents in agroecosystems.

Etymology

From Platygaster (type genus), Greek platys (broad, flat) + gaster (belly), referring to the flattened abdomen of type species.

Example

Platygaster hiemalis, a common Platygastridae species, parasitizes eggs of the Hessian fly (Mayetiola destructor), providing natural suppression of this major wheat pest.

Synonyms

• Platygasteridae (obsolete spelling)

Related Terms

• Parasitoid
• Hymenoptera
• Platygastroidea
• Cecidomyiidae
• Biological control
• egg parasitoid
• Flagellum
• geniculate antennae
• microhymenoptera

Usage Notes

Spelling stabilized as Platygastridae (not Platygasteridae) following modern nomenclatural revisions. Often confused with Scelionidae, a related platygastroid family with similar habits but distinct wing venation and antennal structure. The family's minute size and reduced wing venation make specimens challenging to identify without slide-mounting and high-magnification microscopy.