Phylloxera glabra (von Heyden, 1837)
oak-leaf phylloxera
on Quercus

Quercus robur, Hungary, Budapest, 30.iv.2016 © László Érsek: leaf with ear galls

detail

underside of an ear gall
female aphid
female surrounded by a double row of eggs
eggs, detail

30.v.2016 a moth later

the leaf clearly becomes mottled
female aphid
gall
tiny (< 1 mm) orange-yellow aphids on the underside of a leaf. The aphids of the early spring generation cause “ear galls”. Later generations do not cause any galling, but their suction activities create numerous small yellow spots.The females deposit large numbers of shining yellow eggs in a concentric circle.
host plants
Fagaceae, narrowly oligophagous
Quercus robur.
Rarely also other deciduous oaks.
notes
for the difference with Ph. coccinea check there.
references
Barson & Carter (1972a), Blackman & Eastop (2014), Börner (1957a), Burton, Ellis & Schneider (2022a), Coulianos & Holmåsen (1991a), Hellrigl (2004a), Krzywiec (1982a), Lambinon & Schneider (2004a), Lampel & Meier (2003a), Lubiarz (0000a), Osiadacz & Wojciechowski (2008a), Redfern & Shirley (2011a), Ripka, Reider & Szalay-Marzsó (1998a), Roskam (2009a), Wojciechowski, Depa, Halgoš ao (2016a).