First report of oak lace bug, Corythucha arcuata, in Austria
Markus Sallmannshofer, Sophie Ette, Werner Hinterstoisser, Thomas L. Cech, Gernot Hoch
The American oak lace bug Corythucha arcuata (Say, 1832) (Heteroptera, Tingidae) has severe impact on oak forests in parts of its invasive range in Europe. Here we report the first finding of C. arcuata in Austria. A screening in south-eastern Austria in September 2019 confirmed the occurrence of C. arcuata on 21 sites. The intensity of infestation varied considerably between 1 % and 95 % of leaves per tree and correlated with average leaf discolouration. Compared to investigations in the project REFOCuS the intensity of infestation seems to be dependent on human activities on the site. We assume that the spread of C. arcuata initially took place along main traffic and tourist routes. Thus, the quick spread is likely caused by passive transportation on vehicles. The first assessment gives evidence that C. arcuata is already widespread and established in south-eastern Styria and southern Burgenland. Massive feeding damage on oak foliage is expected in the upcoming years.
First record of the entomopathogenic fungus Entomophaga maimaiga in gypsy moth populations in Austria
Gernot Hoch, Daniela Pilarska, Margarita Georgieva, Georgi Georgiev, Plamen Mirchev und Christa Schafellner
The entomopathogenic fungus Entomophaga maimaiga, a native of East Asia, was recorded in gypsy moth (Lymantria dispar) populations in Austria for the first time in summer 2019. Light microscopic examination of dead L. dispar larvae, collected in a forest near Eggenburg (Lower Austria) that suffered complete defoliation, showed a prevalence of E. maimaiga of 64.8 %. Prevalence in dead larvae collected in a forest near Ebergassing (Lower Austria) was 100 %. These larvae also showed the typical macroscopic symptoms of E. maimaiga infections. Surveys on these two sites in 2018 did not reveal the presence of the fungus. Cool and rainy conditions in May 2019 were probably optimal for infections of gypsy moth larvae. E. maimaiga has been spreading quickly from the Balkan Peninsula to Central Europe since its first introduction to Bulgaria in 1999 and consecutive releases. The fungus will likely become a further effective natural enemy of L. dispar in the oak forests of Austria that will have marked impact on the population dynamics of this defoliator.
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