Andricus fusiformis Pujade-Villar n. sp.

Gall (Figs 3a-c) galls are developing on thin branches of Q. obtusata. It is a plurilocular gall, woody, more or less fusiform (35-45 mm in length and 12-18 mm in diameter), composed by different subunits more or less fused. Coloration gray with green tones; adults emerge before the gall becomes hard and take a woody brown color. The surface is glabrous with some longitudinal grooves on the mature gall. The inner larval chambers are located in the internal tissues; when the gall is cracked we can observe the larval chambers inside the crack. The single larval chamber is globular (2.6 mm. of diameter), dirty yellow, with a hard woody wall (0.3 mm think), which is connected with the tissue of the gall by a basal peduncle; at the top there is a small umbilicus.

Host plant Quercus obtusata Humb. & Bonpl. (section Quercus of Quercus, white oaks), distributed in many states of Mexico at 620–2580 m a.s.l. (Valencia, 2004). Galls collected in branches of Q. crassifolia Humb and Q. rugosa Née in the same area of type material are similar but no adults have emerged; we cannot assure these galls are the same of collected in Q. obtusata, although all of them belong to the Quercus section.

Distribution Currently known only from Mexico State. Galls were collected in San Juan Coajomulco (Jocotitlan).

Biology Only the asexual (parthenogenetic) females are known. Galls develop in dry season and adults emerge in July. No parasitoids emerged, only Synergus on 24.vii.2014.

- Juli Pujade-Villar, Rosa D Garcia-Martinon, Armando Equihua-Martinez, Edith Estrada-Venegas, Mar Ferrer-Suay: (2014) A new Mexican species (Hym., Cynipidae) inducing tuberous galls in twigs of oaks (Fagaceae)^©