Andricus stellaris, new species

A hemispherical gall, 3-4 mm in diameter and 2 mm. high, covered with short, blunt crystalline protuberances with a circle of 12-15 longer, broad and flat projections at the base resembling an open specimen of a many-rayed species of the fungus. Attached singly or scattered in small numbers on the underside of the leaf in the fall. The galls are yellowish-white, often tinged with red. The larval cell lies transversely in the very base of the gall and above it is a cavity above which the crystalline wall of the upper part of the gall is very thick.

Host:
Quercus garryana

Andricus stellaris

Quercus douglasii, garryana
Leaf galls, detachable
Fig 158. Hemisperical, rugose, on under side.

Fig 158. Q-garryana, douglasii. On under side leaf in fall, 2–5 mm. in dia., whitish, often tinged with red. Galls collected at Willits in October contained living adults the next February.

Andricus stellaris

This cynipid wasp induces convex, round, monothalamous galls with radiating crystalline projections on the underside of leaves of blue and Oregon oaks.

Hosts:
Quercus douglasii
Quercus garryana

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

Gall (Fig. 366). A hemispherical gall, 3–4 mm in diameter and 2 mm high, covered with short, blunt crystalline protuberances with a circle of 12–15 longer, broad projections at the base, attached singly or scattered in small numbers on the underside of the leaf. The galls are yellowish-white, often tinged with red. The larval cell lies transversely in the very base of the gall and above it is a cavity above which the crystalline wall of the upper part of the gall is very thick (Weld 1926).

Biology. Only the asexual generation is known, which induces leaf galls on Q. douglasii and Q. garryana (section Quercus, subsection Dumosae) in autumn, the adults emerge the next spring in March (Weld 1926).

Distribution. USA: California (Burks 1979).