Cynips quercusfolii Linnaeus, 1758

Quercus, agamous generation

Cynips quercusfolii: gall on Quercus robur

Quercus robur, Belgium, prov. Hainaut, Comines, 6.viii.2019 © Martin Windels

Cynips quercusfolii: gall on Quercus robur

galled lead, upper side

Cynips quercusfolii: gall on Quercus robur

gall at the underside; see note below

Cynips quercusfolii: galls on Quercus robur

two more galls

Cynips quercusfolii: gall on Quercus robur

Quercus robur, Bergen aan Zee, 2.ix.2012

Cynips quercusfolii: ripe galls drop to the ground

Generally the galls remain attached to the leaf until autumn, then drop with the leaf to the ground, but sometimes the galls drop spontaneously (?) already in late summer.

Cynips quercusfolii gall

Hollandsche Rading: opened gall; the gall is soft and juicy

Cynips quercusfolii gall

the small larval chamber

Cynips quercusfolii gall

Wolfheze, 6.x.2007: hibernation as imago in a gall that has fallen to the ground

Cynips quercusfolii on Quercus robur: extremely heavy infestation

Nieuwendam, 8.ix.2012: extremely heavy infestation of a small tree in the bank of a main highway

Gall

Galls from July till October, mature in August.

host plants

Fagaceae, monophagous

Quercus frainetto, macranthera, petraea, pubescens, pyrenaica, robur.

Rarely also Q. cerris.

inquilines

Archarius pyrrhoceras.

notes

Normally the surface of the gall si completely smooth, but galls with a tuberculare surface do occur as well. Redfern & Shirley write that this occur in galls on Quercus petraea, but this cannot be the complete explanation. The statement by Buhr thit is exclusively concerns parasitised galls needs confirmation.


Quercus, sexual generation

Cynips quercusfolii: sexual gall on Quercus petraea

Quercus petraea, Belgium, prov. Namur, Couvin, Frasnes © Stéphane Claerebout: group of dormant buds with two young galls

Cynips quercusfolii: sexual generation gall on Quercus robur

Quercus petraea, Belgium, East Flanders, Geraardsbergen, Overboelare-Planken @ Bart Uitterhaegen: as the galls grow older, the colour changes from reddish to dark purple

gall

The sexual generation makes egg-shaped, velvety galls of about 2 mm on resting buds; initially they are red. Contrary to Cynips longiventris, at the base of the gall remnants of bud scales are visible.

host plants

Fagaceae, monophagous

Quercus frainetto, x hispanica, infectoria, petraea, pubescens, pyrenaica, robur.

Rarely also Q. cerris.

synonyms

Dryophanta folii Hartig, 1840; D. scutellaris Olivier, 1781; D. flosculi (Giraud, 1868); D. taschenbergi (von Schlechtendal, 1870).

notes

In the agamous generation there is a significant preference for the larger leaves (Giertych ao, 2013a).

references

Abras, Fassotte, Chandelier & Cavelier (2008a), Béguinot (2002a,e,f,g,h, 2003a, 2006a,c, 2007b, 2012a), Bellmann (2012a), Blanes-Dalmau, Caballero-López & Pujade-Villar (2017a), Cerasa (2015a), Chinery (2011a), Cogolludo (1921a), Coulianos & Holmåsen (1991a), Dauphin & Aniotsbehere (1997a), Dietrich (2016a), Eady & Quinlan (1963a), Ecott (2012a), Giertych, Jagodziński & Karolewski (2013a), Groom (2011a), Guzicka, Karolewski & Giertych (2017a), Hellrigl (2009a, 2010a, 2012a), Hellrigl & Bodur (2015a), Houard (1908a), Ilie & Marinescu (2011a), Jankiewicz, Dyki, Machlatiska & Dubert (2017a), Katılmış & Kıyak (2008a), Kemal & Koçak (2010a), Kollár (2007a, 2011a), Koops (2013a), Kwast (2012a, 2014a), Lambinon, Carbonnelle & Claerebout (2015a), Lambinon, Schneider & Chevin (2003a), Lehmann & Hannover (2016a), Marković (2014a, 2015a), Melika (2006a), Melika, Csóka & Pujade-Villar (2000a), Mete & Demirsoy (2012a), Nieves-Aldrey (2001a), Pellizzari (2010a), Redfern & Shirley (2011a), Roques, Cleary, Matsiakh & Eschem (2017a), Roskam (2009a), Tomasi (2003a, 2012a, 2014a), Williams (2010a).

mod 8.viii.2019