Xanthoteras tubifaciens, new species

Host. — Quercus garryana.

Gall (fig. 41). — A convex mass of tubular galls standing side by side in a compact cluster on the underside of the leaf in the fall. The mass measures up to 25 mm. long by 15 mm. wide. The individual galls are easily detached, especially in preserved specimens, white or cream-colored, up to 9 mm. long, tapering gradually from the base to a diameter of about 3 mm. at the distal open end, the distal portion beset with tapering spines which are often rosy at the tip. The single larval cell lies midway of the length of the gall and measures about 2 mm. long by 1.2 mm. in diameter. The tissue of the dried galls is of crystalline hardness so that the insects are unable to chew their way out of preserved specimens.

Habitat. — The type material was collected September 8, 1922, in Sequoia National Park, Calif., just above the Cedar Creek checking station on the road to Giant Forest. At that time the galls contained full-grown larvae. Living flies were cut out of the galls on November 10. These galls were seen just starting to develop at McLeod, Oreg., on July 22. They were also seen at Yreka, Calif., and the Stanford collection has galls from Siskiyou, Oreg.

Trichoteras tubifaciens (Weld).

Quercus garryana
Leaf galls, detachable
Fig 154. Close together, 9 mm high, under.

Fig 154. Q-garryana. Galls 9.0 mm. long stand close together in a mass on under side of leaf. Adults were cut out Nov. 10 from galls collected in early Sept. (Sequoia National Park).

This cynipid wasp induces unique, tubular galls with short, crystalline bristles on the underside of leaves of Oregon oak. These midrib, monothalamous galls usually occur in tight clusters of up to 35 individual galls.

Feron tubifaciens (Weld, 1926) comb. nov.

Gall (Fig. 475). Convex mass of tubular galls standing side by side in a compact cluster on the underside of the leaf. The mass measures up to 25 mm long by 15 mm wide. The individual galls are easily detached, white or creamcoloured, up to 9 mm long, tapering gradually from the base to a diameter of about 3 mm at the distal open end, the distal portion covered with tapering spines which are often rosy at the tip. The single larval cell lies midway along the length of the gall and measures about 2 mm long by 1.2 mm in diameter (Weld 1926).

Biology. Only the asexual generation is known, inducing galls on Q. garryana (section Quercus, subsection Dumosae) (Weld 1926, Burks 1979). Galls mature in October-November.

Distribution. USA: California.