Andricus confertus new species

Gall--A rounded, closely packed mass of galls occurring on the midribs or lateral veins on the undersides of leaves (rarely on upper side). The masses are from 6 to 8 mm long and almost as wide, each mass containing from few to 20 or more galls. Each gall is rounded on the outer surface and compressed basally. Easily detached when ripe and deciduous. Color pink or rose when fresh, tan when old and dry; 1 to 3 mm in diameter. Monothalamous.

Host: Quercus lobata

Type locality.--Stanford campus Santa Clara county CA

Note.--This species is described from ten females cut out in March from galls collected in November and December. Many galls opened in March contain insects still in larval stage.

Andricus confertus

Quercus lobata
Leaf galls, detachable
Fig 105. Midrib cluster below, pubescent.

Fig 105. Q. lobata. Galls start to develop in July. Those collected Nov. 21, 1955 contained pupae Oct.10, 1956 and adults emerged Mar. 20, 1957 (Kelseyville).

Andricus confertus

This cynipid wasp induces convoluted, brain-like midrib clusters of detachable, monothalamous galls with fine hairs on the underside of leaves of valley oak.

Host:
Quercus lobata