Andricus bakkeri (agamic)

Pinched Leaf Gall Wasp

Cynipidae

Feron

Quercus berberidifolia

California

Quercus cornelius-mulleri

Quercus dumosa

Quercus engelmannii

Quercus garryana

Oregon

Washington

British Columbia

New Cynipid Wasps from California (Hymenoptera: Cynipidae)

Feron bakkeri (agamic)

Andricus bakkeri

Gall:
A monothalamous, cup-shaped leaf spangle, 3-3.5 mm in height. The larval cell occupies the base of the cup whose margins are collapsed at maturity. The galls appear on the leaves during the early summer months and grow rapidly until they reach full size in August. At this time the galls are red and contain small larvae. Pupation occurs in late October and early November.

Hosts:
Quercus dumosa 
Quercus engelmanni
Quercus garryana

Range: La Crescenta CA

Andricus bakkeri

This cynipid wasp induces beige-pink monothalamous galls on the underside of leaves of Oregon and scrub oaks. These detachable galls usually occur in large numbers per leaf and appear as though they are pinched inward, like pursed lips. 

Range:
Observed by Russo near Cave Junction, OR, although they were described from a site in southern CA. 

Host:
Quercus garryana
Quercus berberidifolia

Plant Galls of the Western United States

Quercus cornelius-mulleri added tentatively as a host based on [this unconfirmed observation](https://www.inaturalist.org/observations/102648049) and the fact that Q. cornelius-mulleri was considered part of the Q. dumosa species complex until 1981.

Gallformers ID Notes

Feron bakkeri (Lyon, 1984), comb. nov.

Gall (Fig. 71). A monolocular, cup-shaped leaf spangle gall, 3–3.5 mm in height. The larval cell occupies the base of the cup whose margins are collapsed at maturity (Lyon 1984).

Biology. Only the asexual generation is known, which induces galls on Q. dumosa (section Quercus, subsection Dumosae). The galls appear on the leaves during the early summer until August. At this time the galls are red and contain small larvae. Pupation occurs in late October and early November; adults can be cut out in early December; however, normal emergence takes place in February–March, or even later.

Distribution. USA: California (Lyon 1984).

Re-establishment of the Nearctic oak cynipid gall wasp genus Feron Kinsey, 1937 (Hymenoptera: Cynipidae: Cynipini), including the description of six new species