Andricus tubalis

Quercus arizonica, oblongifolia
Stem galls
Detachable
Fig 59. June.

Andricus tubalis, new species

Host. — Quercus arizonica.

Gall (fig. 21). — Arising from a weak bud on small twigs, usually on wood of previous year, easily detachable. Trumpet-shaped, the outside fluted, tapering to a sessile or clasping base, the flaring end forming a shallow cup in the bottom of which is the exit hole, 5-8 mm. long, cup up to 7 mm. in diameter. yellowish-white in color. The single larval cell lies longitudinally in the cylindrical stem of the gall, no false cavity present.

Habitat. — The type material was collected June 22, 1918, at Oracle, Ariz. The two adults emerged and died before August 23, Empty galls were seen at the same locality in December, 1921. Precisely similar galls were observed on Q. oblongifolia at Nogales.

Andricus tubalis
Flared-disc-gall wasp

Hosts: Quercus oblongifolia, arizonica

The monothalamus, flared galls of this wasp occur on small twigs of last year's growth on Arizona white and Mexican blue oaks. Galls develop from weak buds. The flared top tapers in to a sessile or slightly clasping base.