Striatoandricus tenuicornis (Bassett, 1881), comb. nov.

Cynips tenuicornis Bassett, 1881: 92, female, gall.
Diplolepis tenuicornis (Bassett): Weld 1926: 34.
Andricus tenuicornis (Bassett): Weld 1951: 636.

Galls. Densely hairy hemispherical masses attached by a single small point to the upper or under surface of the leaves. They are from 10-20 mm in diameter. The woolly hairs are of a dull russet color and entirely hide the polythalamous gall beneath. The gall interior contains small and extremely thin-walled larval cells. Between them there are a few thin fibrous plates or lamellae separating open spaces. An average size gall contains 14 larval cells (Bassett 1881).

Biology. Only an asexual generation is only known, inducing galls on Q. arizonica.

Distribution. USA: Arizona, Mule Pass Mountains (Bassett 1881).

Andricus tenuicornis

Quercus arizonica
Leaf galls
Detachable
Wool dull russet, many-celled

Diplolepis tenuicornis

This species was described from an unknown oak from the Mule Pass Mountains, Ariz. The type galls in the American Entomological Society seem to be on Q. arizonica. The writer collected galls on arizonica in December at Oracle in the Santa Catalina Mountains and reared adults in March.