Burnettweldia conalis (Weld 1926), comb. nov.
Asexual

Hosts: Quercus garryana, berberidifolia [see ID Notes]

[A photo of the gall appears on page 32 of the pdf]

Gall. (Fig 92). Detachable monolocular stem galls, pointed, conical, glabrous, occur singly or in clusters of 2–5. The gall is 12–15 mm high and 8–9 mm wide at the base; sides of the gall are smooth; the base of the gall wraps over the stem; larval chamber centrally positioned in the gall base and perpendicular to the gall vertical axis. The parenchyma tissue is soft, not woody, epidermal layer thin; color of growing galls pale green with white pile which turns reddish; mature galls light brown, old galls dark brown to black, not deciduous (Burnett 1977, Russo 2006).

Biology. Galls develop in summer; adults emerge in early autumn. Galls on Q. berberidifolia, Q. garryana (Burks 1979)

Range: CA, Sierra Nevada mountains

Weldia conalis, new combination

Disholcaspis conalis

Gall: Monothalamous stem galls occurring singly or rarely in clusters of 2-5, never found on host tree in large numbers; conical in outline with entire gall drawn out to gradually tapering at apex, straight in some, bent over or lopsided in others; base above point of attachment abruptly flared and symmetrically spherical in some, irregluar and clasping stem in others; internally thin-walled, oval, larval capsule centrally positioned in the gall base at its broadest point and situated perpendicular to the galls vertical axis; parenchymal tissue soft, but dense (not woody); epidermal layer thin; surface basically smooth, slightly folded in some; color of growing galls pale green with short, white pile which turns reddish and weathers off at maturity; mature galls light brown, old galls dark brown to black; not deciduous. Average size of 50 unparasitized galls; horizontal diameter, 8.5 mm; height, 12.6 mm.

Hosts: Quercus garryana. No other hosts have been recorded, nor have I found galls on hybrids inspected near the type locality.

Range: Known only from a few locations of the western slopes of the Sierra Nevada Mountains in central CA. It is apparently not correspondingly distributed with its host Q garryana which ranges from the Liebre Mountains in northern Los Angeles Co to the Canadian border and beyond.

In mid July, 1976, new pale-green galls under 3 mm in diameter were observed bursting through the green bark of young Q garryana stems near Tollhouse CA. Other galls at the locality and at Sequoia Park were nearly full grown at this time, but still green in color and bearing a recumbent, whitish pile which was beginning to turn rusty red on larger galls. Fresh galls were growing directly from stems and none observed were associated with either terminal or axillary buds at that time. Large galls, those 8-10 mm high and 6-8 mm in diameter at the base, contained 3rd and 4th instar larvae housed in a moist, thick-walled larval capsule which later becomes so thin as to be barely noticeable in the dry mature galls.

[From key to galls, page 176 of the pdf]

1. Spherical or cone-shaped stem galls, usually with an apical projection or strong surface tubercles

2. Surface smooth; pointed apically

3. Entire gall drawn out into conical shape, broadened or clasping at base; green when young, light brown when mature; surface smooth or slightly longitudinally folded; larval capsule basal, oval; host specific to Q garryana in central California

Disholcaspis conalis

Quercus garryana
Stem galls, detachable from the twig
Fig 90. Conical, 12-15 mm. high, in fall.

Fig.90. Q-garryana • Adults issued and died in box before October 1.

Disholcaspis conalis, new species

Conical, 10-18 mm. high, with a clasping base 8-12 mm. in diameter, the tapering apex often lopsided, single or in small clusters on small twigs in the fall. Greenish when growing and covered with dense short white pubescence which rubs off after the galls begin to harden. They start to develop late in May and mature in September. Old galls are tan-colored. The interior consists of dense cellular tissue with a transversely placed larval cell, not separable and without a distinct lining wall.

Host:
Quercus garryana

Habitat. — The type material was collected September 8, 1922, in Sequoia National Park, Calif., just above the Cedar Creek checking station on the road from Kaweah to Giant Forest. Some flies issued and died in the packet before October 1, while others died inside, not being able to chew out of the hard galls.

Disholcaspis conalis

This cynipid wasp induces pointed, conical, glabrous, monothalamous stem galls on Oregon oak. These detachable galls develop in summer and occur singly or in groups, separated along the length of a branch.

Host:
Quercus garryana