Description of the sexual generation of Trichagalma acutissimae (Hymenoptera: Cynipidae) and notes on its heterogonic life cycle

The adults and galls of the sexual generation of the oak gall wasp Trichagalma acutissimae (Monzen, 1956) (Hymenoptera: Cynipidae) (=T. glabrosa Pujade-Villar n. syn.) are described for the first time. The heterogonic life cycle of T. acutissimae has been established experimentally in a field trial. We also provide information on the taxonomy, biology and host plant. A key to species of Trichagalma including both sexual and asexual generation is given. [Display omitted] •The adults and galls of the sexual generation of the oak gall wasp Trichagalma acutissimae (Monzen) are described.•The alternating life cycle for T. acutissimae has been established experimentally for the first time.•A key to species of Trichagalma including both sexual and asexual generation is given.