Neuroterus saltatorius var. decrescens Kinsey

Quercus arizonica
Leaf galls
Detachable
Ellipsoid, twice as long as wide, with short hairs, similar to the jumping gall on the valley oak in California.

Neuroterus saltatorius variety decrescens, new variety

GALL. — Elongate, twice as long as wide, up to 0.7 mm. in length; the surface microscopically roughened, irregularly set with a short pubescence; brownish or tinged purplish red; on Quercus arizonica (fig. 29).

RANGE. — Arizona: Bisbee, Prescott. Probably confined to Q. arizonica in a southwestern portion of the U.S. and adjacent Mexico.

This insect is closely related to the other varieties of saltatorius, but the galls are so distinct as to suggest that decrescens may belong to a distinct species. Until we can breed more material from all of the pubescent, separable galls of the southwestern evergreen oaks, there will be a question as to their specific relations. This is true for the present insect and for an undescribed species producing a more spherical, more pubescent gall on Q. grisea in West Texas. Decrescens is one of the three or four smallest Cynipidae known.