Illustrated identification guide to the Nordic aphids feeding on Conifers (Pinophyta) (Insecta, Hemiptera, Sternorhyncha, Aphidomorpha) Author Albrecht, Anders Christian text European Journal of Taxonomy 2017 2017-07-24 338 1 160 journal article 22023 10.5852/ejt.2017.338 be9f3ab9-3131-4e11-8d29-a94275ffaac9 2118-9773 3834349 86786AB1-4A1A-4A1E-B42B-53B73D66ED60 Pachypappa vesicalis Koch, 1856 Diagnosis Holocyclic, dioecious, alternating between Populus alba (Salicaceae) and Pinaceae : Picea and Pseudotsuga . Recorded secondary hosts Pinaceae : Picea abies * , glauca , sitchensis ; Pseudotsuga menziesii . Distribution F S.