Chalcidoidea

Definition

A superfamily of minute parasitoid wasps in the order Hymenoptera, encompassing approximately 22,500 described species in 20+ families and an estimated 500,000+ species total. Chalcidoidea are characterized by reduced wing venation, often elbowed antennae with a clubbed tip, and a metapleuron that is broadly fused to the mesosoma. The vast majority are parasitoids of other insects, with many species employed in classical biological control; a minority are phytophagous, forming galls or feeding in seeds. The group includes the smallest known insects (fairyflies, family Mymaridae) and is among the most species-rich radiations in terrestrial ecosystems.

Etymology

From Chalcis (type genus of family Chalcididae, from Greek khalkos 'copper,' referring to metallic coloration) + -oidea (superfamily suffix).

Example

Trichogramma (family Trichogrammatidae) and Copidosoma (family Encyrtidae) are chalcidoid genera widely mass-reared for augmentative biocontrol of lepidopteran crop pests.

Synonyms

• chalcidoid wasps
• chalcid wasps (informal; note 'chalcidid' refers only to family Chalcididae)

Related Terms

• Hymenoptera
• Parasitoid
• Biological control
• Mymaridae
• Trichogrammatidae
• Encyrtidae
• Pteromalidae
• Eulophidae
• Apocrita
• metapleuron
• wing venation

Usage Notes

Specialists use 'chalcidoid' for members of the superfamily; 'chalcidid' is restricted to family Chalcididae. The superfamily is morphologically diverse, and family-level identification typically requires slide-mounted specimens and examination of mesosomal sclerites and antennae segmentation. Many species remain undescribed, particularly in tropical leaf litter and canopy samples.