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).