Biorhiza eldoradensis (Beutenmuller)
Andricus eldoradensis Beutenmuller
They were from Ashland, Oregon, reared from acorns of califomica of the 1914, crop, collected by P. D. Sergent on September 5. 1914. Unfortunately no acorns were preserved, but the adults were said to occur "in gall pockets on the inner surface of the acorn shells" and 8 were obtained from three acorns. The flies emerged September 5-October 7, 1914.
Host.—Quercus agrifolia Nee, Quercus densiflora Lindley, and Quercus californica Cooper.
Gall.—The gall produced by this species is undescribed. Separate woody cells are produced in the acorns, which are somewhat distorted in shape and usually undersized (fig. 1). They are always in the lower third of the acorn and the cell is adherent to the wall of the acorn and not separable from it, projecting slightly into the interior cavity, which has a velvety lining and may contain traces of the cotyledons. An acorn may contain from one to half a dozen of these cells at various points around its periphery and the flies make separate holes to the exterior through the acorn cup. Occurs in late summer and autumn in acorns of current season's crop.
At the time the species was first described, it was associated with a stony mass of galls more or less filling the interior of the acorn, the work of a new species described in the present paper as Callirhytis milleri Weld, page 11. Although this stony gall and the Eldoradensis flies bore the same Koebele number, Beutenmueller suggested that the two might have nothing to do with each other. C. milleri produces a confluent mass of cells in the interior which can be lifted out intact; Eldoradensis produces separate cells in the base of acorn not separable from the wall. The type galls of Eldoradensis consist of one acorn of each kind. The writer has seen both species working in the same acorn, but the two types of work are easily recognized.
Habitat.—Acorns of Quercus agrifolia affected by this species have been seen by the writer at Newhall, Piru, Fillmore, in Ojai Valley, Montecito, Santa Barbara, Paraiso Springs, Los Gatos, Berkeley, and St. Helena, California. Those of Quercus wislizeni in San Gabriel River canyon above Azusa, at Santa Margarita, Los Gatos, and Bagby, California.