Heteroecus malus

This wasp induces round, monothalamous spring galls in grapelike clusters on branches of canyon live oak.

Host:
Quercus chrysolepis

Heteroecus malus, new species

Hosts: Quercus chrysolepis

GALL. — Ovoid to almost absolutely spherical, 8.-16. mm., in diameter, only very slightly drawn into a point for attachment basally, and with a very fine, very short point apically 1.0 mm. or much less in length; entirely smooth and naked, or the surface slightly roughened, light to dark green when fresh, tinged with rose red, upon aging becoming brown. Internally more or less solid, with a single larval cell centrally, closely embedded, and between the cell and the base only a discontinuous cavity indicating the usually cylindrical cavity of the species. Singly or in compact clusters of a dozen, more or less, laterally or terminally on twigs of Quercus chrysolepis.

RANGE. — California: Pasadena, San Bernardino.

This variety comes near bakeri, but is distinct enough. The manner of oviposition, many eggs being laid in a restricted area, is distinct from bakeri. Material from the San Bernardino Mountains is remarkably uniform in respect to both the insect and the gall. Material from outside the San Bernardinos, that is, from another faunal area, shows some considerable variation, a part of the Pasadena material fully matching that from the San Bernardinos. I cannot decide whether there are other varieties of this species until I can examine more material. It is not impossible that this should be considered a variety of H. chrysolepidis.