Disholcaspis erugomamma Cooke-McEwen, sp. nov.

[A photo of this gall is included on page 19 of the pdf]

Gall (Fig. 47): Reddish brown, globular with a short, obtusely pointed nipple apically or few may lack the nipple entirely. Dispersed or more commonly tightly clustered and deforming around each other. Internally with dense, rather hard, corky texture; larval cell not free in galls examined. Gall is most similar to that of D. quercusmamma, but the surface is wrinkled in that species and relatively smooth in D. erugomamma. It is uncertain if the galls are nectar secreting, but the black sooty mold that is typical for mature nectar secreting galls was lacking. The galls were covered in dust when found but it is uncertain if that dust was a trait of the gall itself as opposed to its dusty arid environment near a road.

Biology: Only the asexual generation is known at this time. All wasps reared for this study emerged toward the end of December or early January.

Etymology: Named for the gall morphology. From Latin, erugo meaning to free of wrinkles (noun in apposition) and mamma as a reference to the mammiform gall shape (Brown 1956).

Distribution: Known only from the single collecting event in western Texas. Collecting site was revisited in spring 2020 and empty fall galls were present.

Host plant remarks: The host plant voucher is deposited at MARY and identified as Q. havardii. It has a small range from northwestern Texas to New Mexico and Oklahoma, with disjunct populations in northern Arizona and southern Utah (Nixon, 1997).