First record of Micromus variegatus (Fabricius) (Neuroptera: Hemerobiidae), an accidentally introduced Palearctic species, in the United States

Abstract

One specimen of Micromus variegatus (Fabricius 1793) (Neuroptera: Hemerobiidae) was collected in the city of Moscow in northern Idaho. The specimen data are: U.S.A.: Idaho: Latah Co.: Moscow, elev. 840 m, 8 August 2010, M. M. Furniss. The specimen was found on the wall of a house in an area with diverse vegetation, including coniferous and deciduous trees, shrubs and herbaceous species that support a diversity of potential prey. The specimen was initially recognized on the basis its distinctive wing markings (Fig. 1). Its identity was confirmed using identification keys (Aspock et al. 1980) and by comparison with authoritatively determined material from Europe. The specimen is deposited in the William F. Barr Entomology Museum at the University of Idaho. This is the first reported specimen of M. variegatus from the United States. The species was first reported in North America in British Columbia, Canada (Klimaszewski & Kevan 1988). Those authors suggested that the species was introduced from Japan. It is now reported from five localities in southern BC (Scudder & Cannings 2009). Micromus variegatus is also known in eastern Canada with 14 specimens from Saint-Laurent-de-Ile-d Orleans, Quebec (Klimaszewski et al. 2009). That population is believed to be the result of an independent introduction from the British Isles or Western Europe. The discovery of M. variegatus in Idaho, approximately 480 km from the nearest known site in Penticton, BC, and 700 km from the original North American collection on Galiano Island near Victoria, BC, provides additional documentation of the establishment and spread of this species in North America. Its broad geographical and ecological distribution in Eurasia, from the British Isles through Iran and other arid areas in the Middle East to Japan (Aspock et al. 1980, Aspock et al. 2001), suggests that it could ultimately become widespread in North America. Its impact on native lacewing populations, especially native species of Micromus, should be monitored if M. variegatus increases in abundance. We thank John Oswald for his assistance in locating the relevant literature and reviewing the manuscript, Sean McCann, Simon Fraser University, Burnaby, BC, Canada, for the use of his photograph, and Subject Editor Eric Benbow for helpful comments.