''Phylloteras cupella'', formerly ''Trigonaspis cupella'', also known as the urn gall wasp or the banded urn gall wasp, is a species of cynipid wasp that induces leaf

gall Galls (from the Latin , 'oak-apple') or ''cecidia'' (from the Greek , anything gushing out) are a kind of swelling growth on the external tissues of plants, fungi, or animals. Plant galls are abnormal outgrowths of plant tissues, similar to be ...

s on a number of oak species in western North America. Host species include Arizona white,

blue Blue is one of the three primary colours in the RYB colour model (traditional colour theory), as well as in the RGB (additive) colour model. It lies between violet and cyan on the spectrum of visible light. The eye perceives blue when obs ...

Engelmann Engelmann may refer to: * Engelmann Oak, also called Pasadena Oak * Engelmann Spruce, a medium-sized evergreen tree * Engelmann syndrome, a rare autosomal dominant genetic disorder * Engelmann (surname) See also * Engelman * Engel (disambigu ...

gray Grey (more common in British English) or gray (more common in American English) is an intermediate color between black and white. It is a neutral or achromatic color, meaning literally that it is "without color", because it can be composed o ...

leather Leather is a strong, flexible and durable material obtained from the tanning, or chemical treatment, of animal skins and hides to prevent decay. The most common leathers come from cattle, sheep, goats, equine animals, buffalo, pigs and hogs, ...

, netleaf, scrub, and shrub oaks. In the United States, galls induced by this species of wasp have been documented in California, Arizona, and New Mexico. This wasp is most likely also in Mexico and Canada. The galls usually have an

ombré ''Ombré'' (literally "shaded" in French) is the blending of one color hue to another, usually moving tints and shades from light to dark. It has become a popular feature for hair coloring, nail art, and even baking, in addition to its uses in h ...

gradient: lighter at the top, and darker toward the bottom. New galls may be yellow, red, or mauve, while aging galls display a distinctly purple tint, and old galls ultimately turn brown. The wasp measures 1.3–2 millimeters in length.

References

Cynipidae Gall-inducing insects Hymenoptera of North America Oak galls Western North American coastal fauna Insects of the United States Insects described in 1926 {{Apocrita-stub