Pachypappa populi (Linnaeus, 1758)
on Populus, primary host plant
large upwards embossments of the leaf disk, pale green, yellowish to somewhat reddish. The galled leaf is one at the base of a young shoot; the leaves above have turned fiery red.
Salicaceae, narrowly monophagous
on Picea, secondary host plant
Apterae 0.5-3 mm, pale, on thin mycorrhizal root ends, in large colonies covered by flocculent wax. Some populations live permanently on the secondary host plant. Not attended by ants.
Pachypappella populi; Pachypappa grandis Tullgren, 1925.
Albrecht (2015a, 2017a), Béguinot (2012a), Blackman & Eastop (2014), Börner & Franz (1956a), Buhr (1965a), Danielsson (1974a), Heie (1980a), Tomasi (2014a).