A new, apterous species of Megaphragma Timberlake (Hymenoptera: Chalcidoidea: Trichogrammatidae)

A new species of Megaphragma Timberlake (Hymenoptera: Chalcidoidea: Trichogrammatidae), Megaphragma wolfi Lahey & Polaszek, is described from Costa Rica and the southeastern United States. Both sexes are completely apterous (wingless), representing the first occurrence of this phenomenon in the genus and the first apterous female of the family Trichogrammatidae. Morphological features, and a molecular analysis of two gene sequences (28S rDNA, COI mtDNA), place the new species in the recently established M. polychaetum-group.