Atrusca capronae

The species is identified by the striped oak-apple galls it produces on host oak leaves. The galls can be distinguished from other oak-apple galls by their characteristic striping; however, stripe intensity varies regionally, which may complicate identification in some areas. The specific host association with shrub live oak (Quercus turbinella) provides additional diagnostic context where this host is present.

Adult wasps are small, typical of cynipid gall wasps. The galls produced on oak leaves are the most visible manifestation of this species—these are oak-apple type galls with distinctive striping, the intensity of which varies regionally. Gall coloration and pattern serve as the primary visual cue for field identification.

Oak woodlands and scrublands supporting shrub live oak (Quercus turbinella) in arid and semi-arid regions of southwestern North America. The wasp is tied to the presence of its specific host plant, occurring in habitats ranging from desert scrub to montane oak forests where this oak species grows.

Southwestern North America, with highest observation frequency in Arizona. The species occurs throughout the range of its host plant, shrub live oak, which extends from Arizona into adjacent portions of New Mexico, Texas, and northern Mexico.

Adult wasps are active during periods when host oak leaves are suitable for oviposition, typically spring through early summer. Galls remain visible on leaves for extended periods. Specific phenology data are limited.

Larval wasps feed internally within the specialized gall tissue that the plant grows in response to wasp oviposition. The larvae do not consume normal leaf tissue directly; rather, they induce the plant to produce gall tissue that serves as their food source. Adult wasps are not known to feed.

• Quercus turbinella - hostshrub live oak; primary host plant for oviposition and gall development

Adult females oviposit into leaf tissue using their ovipositor. Eggs hatch into larvae that induce gall formation through secretion of plant growth-regulating substances. Larvae develop within the gall, feeding on the specialized gall tissue. Development completes with pupation inside the gall, followed by adult emergence through an exit hole chewed in the gall wall. The life cycle appears to be univoltine, with one generation per year typical for cynipid gall wasps in this region.

Adult females use their ovipositor to inject eggs into leaf tissue; the ovipositor cannot sting humans. The wasp's entire biology is centered on gall induction and development, with larvae manipulating host plant growth to create protected feeding chambers.

As a gall-former, the species acts as a plant parasite that redirects host plant resources to gall tissue. The galls may provide microhabitat for other organisms (inquilines, parasitoids, predators) within the broader oak gall community, though specific associated species for A. capronae have not been documented.

The species has no known economic or medical importance. The galls are of interest to naturalists and entomologists studying plant-insect interactions and oak gall biodiversity. The wasp poses no threat to humans—it cannot sting, and its galls do not significantly harm healthy oak trees.

• Other Atrusca speciescongeneric species may produce similar oak galls; identification requires examination of gall morphology and host specificity
• Other cynipid oak-apple gall waspsnumerous Cynipidae species induce oak-apple galls; A. capronae distinguished by striped gall pattern and host association with shrub live oak

• cynipidae
• gall wasp
• oak gall
• inquiline
• parasitoid
• hymenoptera
• arizona
• southwestern north america
• quercus
• shrub live oak
• oak-apple gall
• plant-insect interaction
• cecidology

• BugGuide
• Wikipedia
• iNaturalist taxon
• Cynipidae | Beetles In The Bush
• nature | Beetles In The Bush | Page 9
• Insecta | Beetles In The Bush | Page 8
• glades | Beetles In The Bush
• landscapes | Beetles In The Bush | Page 5
• entomology | Beetles In The Bush | Page 7