Callirhytis perfoveata

The green, nearly spherical, succulent, monothalamous integral leaf galls (Figs. 5 & 6) were noted by the senior author in the new growth of Q. wislizenii at Folsom Lake, Placer Co., California.

Callirhytis perfoveata (Kinsey).

Quercus agrifolia, kelloggii, wislizeni
Leaf galls, detachable
Fig 168. Globular, projecting on both sides of leaf, fleshy, green, succulent, dia about 6 mm. May. Mono.

Fig 168. On Q-agrifolia, wislizeni, kelloggii. Green, succulent. Adults had just emerged on May 15 (Los Gatos). Adults in Stanford collection emerged May 15 (McC. & Egb.).

Andricus perfoveatus, new species

Galls (Pl. XXIV, Fig. 8). —Small, fleshy-walled capsules imbedded in the leaf-blade. Monothalamous. Spherical or more elongate, about 6. mm. in diameter (perhaps larger when fresh), leaf-green, drying brown, projecting about symmetrically from either surface of the leaf. The walls are thick, succulent, the cavity (in shriveled galls) about oval, 2. X 3. mm., with a distinct larval cell lining, but the cell inseparable (at least in the shriveled gall). On the very young leaves of Quercus kelloggii.

Range: —California: Santa Rosa and Redding.

At the time the galls were collected they were very fresh and succulent, on the very young, unfolding leaves of the black oaks, but inasmuch as adults emerged from some of these galls, in spite of their immediate shriveling on collecting, it would appear that the insects complete their development in a very short period in the early spring. Such species of cynipids are usually bisexual, so the male may yet be discovered for this species.

Callirhytis perfoveata

This cynipid wasp induces round, monothalamous, integral leaf galls in spring on all species in the black oak group.

Hosts:
Quercus agrifolia
Quercus kelloggii
Quercus wislizeni