Callyntrotus trilobus Nalepa, 1923
deformation and discolouration of the leaves, inrolling of the leaf margin.
despite the confusing identity of the specific name, this is not a synonym of Epitrimerus trilobus, that often is cited as (the only) causer of leaf margin galls in elder. Whether both species co-occur in the same gall, perhaps the one as an inquiline of the other, is not clear.
Farkas (1965a), Skoracka, Lewandowski & Boczek (2005a).