Arnoldiola gemmae (Giraud, 1868)
on Quercus

Quercus robur / Andricus foecundatrix, gall, Belgium, prov. Namur, Couvin, Aublain © Sébastien Carbonnelle

other specimens; the smaller larve in both pictures in all probability is Lestodiplosis necans

Quercus sp., Denmark © Simon Haarder: cocoon in gall of Andricus foecundatrix

larva, dissected out of the cocoon
gall
inquiline in the galls of Andricus foecundatrix on oak. Bivoltine, pupation within the gall in a white cocoon.
larva
prosternum with spatula (from Möhn, 1955a)
synonyms
Cecidomyia gemmae Rübsaamen, 1892.
notes
In the literature the larve is described as being white. Because according to the literature no other cecidomyiid inquiline is known from foecundatrix galls, the Danish material is an unknown species. Possibly it is not a true inquiline, but a detritiphagous species.
inquilines
A. gemmae is predated upon by Lestodiplosis necans.
references
Gagné (2010a), Möhn (1955a), Rübsaamen (1892a), Skuhravá & Skuhravý (2007a), Skuhravá, Skuhravý, Dauphin & Coutin (2005a). Skuhravá, Skuhravý & Dengler (1997a), Skuhravá, Skuhravý, Dončev & Dimitrova (1991a, 1992a), Skuhravá, Skuhravý & Jørgensen (2006a), Skuhravá, Skuhravý & Meyer (2014a).