"Heteroecus" pygmaeus [Russo doubts Kinsey's determination that this wasp belongs to the genus Heteroecus because it is on a white rather than intermediate oak]
Hairy-thorn-gall wasp
[Page 176]

Heteroecus dasydactyli var. pygmaeus

Hosts: Quercus turbinella

These monothalamous galls are densely covered with appressed short white hairs and usually occur in tight clusters of four to six per branch.

Range: southwestern NV

Heteroecus dasydactyli variety pygmaeus, new variety

GALL. — Very similar to that of eriophorus. Each gall short, ovoid, or more usually spindle-shaped, with the tapering point short and strongly curved; more or less smooth. Singly or up to ten in a compact cluster on the twigs. [no host is listed]

RANGE, — California: San Bernardino Mountains; Pasadena (?). Probably confined to the neighborhood of the San Bernardino Mountains.

The gall of this variety closely resembles that of variety eriophorus, but the two can be separated very definitely. Dr. McCracken has compared one of my types with Baker material of eriophorus, and she points out distinct differences as noted under eriophorus. The San Bernardino Mountains constitute a ''mountain island" area with a very distinct geologic history and separated quite definitely from the neighboring San Gabriels, in which latter range Baker collected Kieffer's eriophorus. Six insects from Pasadena and their galls match the San Bernardino material closely, tho most of the Pasadena material belongs to eriophorus.