Life history of the Asian longhorn beetle Anoplophora glabripennis (Coleoptera Cerambycidae) in southern Europe

The Asian longhorn beetle Anoplophora glabripennis is highly polyphagous and widely spread over regions with different climates. Determining the key life-history traits is important for understanding how local conditions affect its successful establishment and to develop adaptive management strategies. Field and laboratory studies were conducted from 2010 to 2012 on an A. glabripennis infestation in Northern Italy, aiming to determine its seasonal phenology, adult beetle longevity, density of successful emergence, infestation age and overwintering life history. Adult beetle emerged from infested trees from 22 May to 28 June. Ninety percent of emergence was reached around 20 July. The first 1% of emergence was accurately predicted by an accumulated degree-day model. In the laboratory, the mean longevity of males and females developed under natural conditions was 27.8 +/- 1.7 and 24.9 +/- 1.8days, respectively. In northern Italy, A. glabripennis largely overwinter as mature larvae in the xylem. The mean density of exit holes was 24.0 +/- 2.7 holes/m(2) of bark, with successful emergence from branches as small as 3.2cm in diameter. Although the infestation was discovered in June 2009, the oldest exit hole found in infested trees dated from 2005.