Cynips (Acraspis) arida, new species
agamic form

GALL. — Small, globular, thick-walled leaf gall with the larval cell filling a large part of the interior. Monothalamous, up to 7.0 mm., averaging under 5.0 mm. in diameter. Strictly spherical when fresh, often shrinking irregularly when dried; the gall sometimes drawn out at the point of attachment; the surface of the gall finely, irregularly shagreened, covered with a stellate pubescence when young, the older galls becoming more naked but still with a whitish puberulence; the younger galls probably whitish or pinkish, the older galls rather dark purplish brown. The thin outer shell re-enforced with a rather thick mass of not very hard, crystalline material, the larval cell highly variable in size, often occupying most of the interior of the gall, the wall of the cell without a distinct cell wall; on leaves of Quercus grisea. Figures 290, 291, 333.

RANGE. — Texas: Alpine (types); Fort Davis. Probably confined to the mountain ranges of western Texas and adjacent parts of New Mexico; related varieties known to occur in more southern New Mexico and Arizona; probably in Mexico. Figure 57.

This is a very common cynipid in western Texas. I have New Mexico and Arizona material that represents at least two other varieties of this species, but none of this material warrants description at this time.

A few of the insects had emerged from the galls which I collected in West Texas in the middle of December (1919). Most of the insects emerged soon after collecting.

It is largely an academic question whether this insect should be considered a variety of Cynips mellea, a variety of Cynips nubila, or a distinct species showing affinities to both mellea and nubila. In general appearance the insect is more like nubila, the smoky patches on the wing giving it a striking if superficial resemblance to that insect; and in many details of structure it shows more than subgeneric relation to nubila . The galls, on the other hand, are so unlike those of nuhila, and so similar to those of mellea that our first decision was to consider this a Southwestern representative of mellea. There are, however, few cases of specific identities among the Cynipidae of more eastern and more western Texas.

- Alfred Charles Kinsey: (1929) The Gall Wasp Genus Cynips^©

Reference: https://www.biodiversitylibrary.org/page/53516882#page/317/mode/1up