A 3-year survey on parasitism of Halyomorpha halys by egg parasitoids in northern Italy

Surveys of stink bug egg parasitism in Asia, Europe and North America, morphological taxonomy, and molecular analysis reveal the Holarctic distribution of Acroclisoides sinicus (Huang & Liao) (Hymenoptera, Pteromalidae)

“…The latter hypothesis can be tested by thorough examination of insect collections that may contain specimens collected prior to the arrival of H. halys. It is noteworthy that we currently have no records of A. sinicus from North America or Europe that predate the arrival of H. halys, with the earliest detection in the USA in 2002 (Grissell and Smith 2006) and the earliest European record in 2016 (Moraglio et al 2019). It should also be noted that one of us (MDM) has studied Pteromalidae in Europe for decades without detecting any specimens of A. sinicus in entomological collections.…”

“…In our study, A. sinicus was found to be associated with H. halys in Italy and P. prasina and H. halys in Switzerland; in the USA it was associated with Euschistus sp., Brochymena sp., C. hilaris, and H. halys; and in Asia it is associated with H. halys, Plautia stali Scott and Erthesina fullo (Thunberg) (Hemiptera: Pentatomidae). In addition, in Italy A. sinicus (formerly identified as A. solus) was recently found associated with Arma custos (Fabricius) (Hemiptera: Pentatomidae) eggs (Moraglio et al 2019).…”

“…Distribution. China (Huang and Liao 1988;Xiao and Huang 2000), South Korea (Ko et al 2018), Canada, USA, Italy, Switzerland; previously recorded for Italy, USA and Canada as A. solus (Grissell and Smith 2006;Gariepy et al 2014;Moraglio et al 2019).…”

“…Emerged parasitoid specimens were stored in ethanol for further taxonomic and molecular analysis. Gahan, 1920 China, Philippines (Canada) Grissell and Smith 2006;Gariepy et al 2014;Moraglio et al 2019 Acroclisoides spilopterus (Masi, 1917) Seychelles n.a. n.a.…”

“…It has since spread north to Canada, where it has been present since at least 2017 (Abram et al 2019;Gariepy and Talamas 2019). Trissolcus japonicus was recently detected in Europe, first in Switzerland in 2017 and then in Italy in 2018 (Sabbatini Peverieri et al 2018;Moraglio et al 2019;Stahl et al 2019). Moreover, T. japonicus is not the only species that has followed H. halys in its worldwide expansion: the Asian egg parasitoid Trissolcus mitsukurii (Ashmead) (Hymenoptera: Scelionidae) was detected for the first time in Europe (northeastern Italy) in 2018 (Sabbatini Peverieri et al 2018).…”