The gall's range is computed from the range of all hosts that the gall occurs on. In some cases we have evidence that the gall does not occur across the full range of the hosts and we will remove these places from the range. For undescribed species we will show the expected range based on hosts plus where the galls have been observed.
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.
