Occurrence of Ixodiphagus hookeri (Hymenoptera: Encyrtidae) in Ixodes ricinus (Acari: Ixodidae) in Southern Italy

Natural enemies of ticks include the parasitoid wasp Ixodiphagus hookeri (Hymenoptera: Encyrtidae). The aim of this preliminary study was to investigate the occurrence of I. hookeri DNA in a community of ticks ( Ixodes ricinus, Dermacentor marginatus, Hyalomma marginatum, Haemaphysalis inermis and Rhipicephalus turanicus). From May 2010 to March 2012, ticks were collected monthly by dragging and flagging, identified, and 481 adults and 305 nymphs screened molecularly for infection with I. hookeri. Of the samples tested ( n = 786), 3.1% ( n = 25) were positive for I. hookeri DNA, 7.2% ( n = 22) in nymphs and 0.6% ( n = 3) in adults. I. hookeri DNA was only detected in I. ricinus. This study shows that I. hookeri infests I. ricinus in southern Italy, with nymphs being the main developmental stage affected by this wasp.