Ormyrus gratiosus ( Foerster , 1860)

Gomez, Jose F., Nieves, Maria Hernandez, Gayubo, Severiano F. & Nieves-Aldrey, Jose Luis, 2017, Terminal-instar larval systematics and biology of west European species of Ormyridae associated with insect galls (Hymenoptera, Chalcidoidea), ZooKeys 644, pp. 51-88 : 60-62

Ormyrus gratiosus ( Foerster, 1860)

Material examined.

ex gall Isocolus scabiosae (Giraud) on Centaurea scabiosa , Spain, Guadalajara: Pozo de Guadalajara, 31.VII.02, J. L. Nieves leg (n = 4); Pozo de Guadalajara, 03.X.04, J. L. Nieves leg (n = 7).

Description.

n = 11; Body length: 2.22 ± 0.63 mm (min-max: 1.40-3.60 mm), width: 1.28 ± 0.31 mm (min-max: 0.67-1.87 mm). The species differs from Ormyrus capsalis in the following characters: head 1.1 times as wide as high; genal area, vertex and first thoracic segment with blister-like sculpture; antennae mid-situated in anterior view of the head; antennal setae 0.35 as long as distance between antennae; lcs situated above lc (Figs 3D, 5D, 7D; Table 2).

Biology.

Larvae of Ormyrus gratiosus are oligophagous idiobiont ectoparasitoids of species of Isocolus that induce galls on flower heads of Centaurea and Serratula species ( Asteraceae ) ( Askew et al. 2006). Additionally, the species has been reared from the galls of Diastrophus mayri on Potentilla argentea ( Rosaceae ). Our examined material was from dissected galled achenes of the flower heads of Centaurea scabiosa in Spain (Fig. 13A, B, and C).