knopper gall

The agamous generation of the knopper gall, Andricus quercuscalicis

Andricus quercuscalicis, knopper gall

gall, early August (photo Hans Jonkman)

Andricus quercuscalicis, knopper gall

same gall, pulled out of the cupula

Andricus quercuscalicis, knopper gall

the “stalk” of the gall has pushed itself between cupula and acorn

Andricus quercuscalicis, knopper gall

The gall is attached to the cupula, next to the attachment of the acorn

Andricus quercuscalicis, knopper gall

The gall chamber, still quite small, is located in the “stalk”

Andricus quercuscalicis, knopper gall

Another specimen, autumn aspect; the gall chamber has grown proportionally

Andricus quercuscalicis, knopper gall

The acorn has been overgrown and is aborted.

mod 5.ix.2017