Tetramesa grandis

Definition

A species of small chalcid wasp in the family Eurytomidae, first described by Riley in 1884. Like other members of the genus Tetramesa, this species is a gall inducer that manipulates host-plant tissue to form nutritive structures sheltering its developing larvae. Tetramesa species are frequently associated with grasses (Poaceae), and their galls can significantly impact host plant growth and seed production.

Etymology

Tetramesa: from Greek tetra- (four) and mesos (middle), referring to four mesopleural bristles characteristic of the genus; grandis: Latin for large or great, likely referring to relative size of the gall or the wasp itself.

Example

Tetramesa grandis induces stem galls on its grass host, with larvae developing inside the swollen plant tissue; such gall-forming chalcids are sometimes studied for their potential as biological control agents against invasive grasses or as models for plant-insect coevolution.

Related Terms

• Eurytomidae
• gall wasp
• Cynipidae
• chalcid wasp
• gall induction
• cecidology
• Biological control

Usage Notes

Tetramesa was formerly placed in family Eurytomidae, though some classifications have historically treated it within separate families; current consensus (GBIF, EOL) places Tetramesa grandis in Eurytomidae. The genus contains numerous species, many poorly studied; identification to species level typically requires examination of gall morphology and adult wasp characters. Not to be confused with the unrelated beetle genus Tetrameres.