Feron vitreum Kinsey, 1937 comb. rev.

Gall (Fig. 501). Individual galls long and slender, uniformly cylindrical or flaring at the top, fairly well covered with distinctly crystalline processes all of which are broad and blunt, filamentous, none of which are fine or hairlike. Galls clustered, forming a spiny mass in which the individual galls are quite prominent, the clusters up to 55 mm in diameter and 17 mm high. Bright purple rose and straw colour when fresh, darkening with age (Kinsey 1937).

Biology. Only the asexual generation is known, which induces galls in October-January, on section Quercus, subsection Leucomexicana oaks: Q. deserticola Trel. (= Q. texcocana Trel.), and Q. rugosa (= Q. rhodophlebia), adults emerge in April.

Kinsey (1937) described another species, F. validum, which we consider is morphologically consistent with Kinsey’s series of specimens of F. vitreum and simply represents a geographical variant of that species; hence we synonymise the name in this study.

Distribution. Mexico: Luis Potosi, Guanajuato (Kinsey 1937).

- Victor Cuesta-Porta, George Melika, James, A. Nicholls, Graham N. Stone, Juli Pujade-Villar: (2023) Re-establishment of the Nearctic oak cynipid gall wasp genus Feron Kinsey, 1937 (Hymenoptera: Cynipidae: Cynipini), including the description of six new species^©