Andricus caepula

Quercus subturbinella [turbinella]
Leaf galls
Detachable
Fig 89 and 168

Diplolepis caepula, new species

Host. — Quercus undulata.

Gall (fig. 32). — Shaped like a small onion, tan-colored, single or scattered in small numbers on under side of leaf in the fall, persisting on the leaf through the winter. The basal third of the sessile gall is beset with long straight single-celled hairs which are mostly reflexed toward the leaf surface. The conical apex is often lop sided and an opening at the end leads into a thin-walled cavity in which are a few scattered hairs and in the base of which is the transversely placed thin-walled larval cell in the very base of the gall. Inside the larval cell at the pedicel is a thin white disk.

Habitat. — The type is selected from a series from galls collected November 14, 1921, near Hillsboro, N. Mex., the flies emerging April 5-25, 1922. Paratypes are from Tijeras, N. Mex., and of the adults cut out of the galls on November 1 some lived in a pill box until December 28. Other paratypes are from Blue Canyon west of Socorro, adults being cut out of the galls on January 2. The galls were seen also at Hackberry, Ashfork, and AVilliams, Ariz. Similar galls were seen on Q. grisea at Magdalena, N. Mex.

Andricus caepula
Bristle-vase-gall wasp

Hosts: Quercus turbinella, oblongifolia

The stiff, crystalline, erect hairs distinguish this species' galls from most other galls, which have crumbled hairs that look like sugar crystals.

Feron caepula (Weld, 1926), comb. nov.

Gall (Fig. 83). Small leaf galls on underside of leaf, 3 mm in diameter with small point in centre of gall, shaped rather like an onion or garlic bulb, pinkish to reddish-brown.

Biology. Only the asexual generation is known, which induces galls on Q. pungens (section Quercus, subsection Polymorphae) and the section Quercus, subsection Leucomexicana oaks: Q. arizonica, Q. oblongifolia, Q. turbinella (Burks 1979). The asexual galls mature by October–November, and adults emerge by April.
Distribution. USA: Arizona, New Mexico (Burks 1979)