Presumed Antistrophus sp.
Silverpuff basal stem gall wasp

Host: Lindley’s silverpuff (Uropappus lindleyi).

Gall location: At the base of the stem.

Description: A spherical swelling, often with dense felt-like pubescence. Greenish to reddish, and apparently around 1-2 centimeters in diameter.

Range: California.

The silverpuff stem gall wasp (see page 23) induces galls on a closely-related host plant, but the silverpuff basal stem gall wasp appears rather distinct, particularly in its location on the host plant and the outer pubescence. The inducer of this gall is unknown, but it is probably a gall wasp closely related to the silverpuff stem gall wasp.