Contarinia pseudotsugae (Condrashoff, 1961) (Diptera, Cecidomyidae): a North American gall midge on Douglas-fir in the northeast German lowlands.
Douglas-fir, a deliberately introduced and established neophyte in Europe, is affected at an increasing rate by damage caused by specialized associated insects, which were introduced to Europe following the host, and native European phytophagous insects, which are adapting more and more to Douglas-fir. The first records in Europe of the North American gall midge species Contarinia pseudotsugae were reported from the Netherlands, Belgium and France in 2015. Twig samples collected from Douglas-fir stands in the German federal state of Brandenburg indicated a distributed occurrence of Contarinia pseudotsugae in the northeast German lowlands. Consequently, a broader distribution of the gall midge in Germany and Europe is to be expected. This study supports the assessment that attempting to eradicate the gall midge is no longer feasible.