Oobius agrili Zhang & Huang, 2005

Triapitsyn, Serguei V., Petrice, Toby R., Gates, Michael W. & Bauer, Leah S., 2015, Two new species of Oobius Trjapitzin (Hymenoptera, Encyrtidae) egg parasitoids of Agrilus spp. (Coleoptera, Buprestidae) from the USA, including a key and taxonomic notes on other congeneric Nearctic taxa, ZooKeys 498, pp. 29-50 : 32

Taxon classification Animalia Hymenoptera Encyrtidae

Oobius agrili Zhang & Huang, 2005 Figures 1-4

Oobius agrili Zhang & Huang in Zhang et al. 2005: 254-258. Holotype female [IZCAS], not examined. Type locality: Changchun, Jilin, China.

Oobius agrili Zhang & Huang: Trjapitzin and Volkovitsh 2011: 671 (key), 672-673 (taxonomic history, host associations, use in biological control for Agrilus planipennis ).

Material examined.

USA, Michigan, Ingham Co., East Lansing, United States Department of Agriculture (USDA) Forest Service Northern Research Station, laboratory culture of Oobius agrili reared in Agrilus planipennis eggs: 37th-generation progeny, emerged 10.viii.2014, D.L. Miller, originally from CHINA, Jilin (Jingyuetan Forest Park, Changchun), 2006, T. Zhao (Zhao Tonghai), from eggs of Agrilus planipennis [10 ♀, UCRC]; 6-7th-generation progeny, emerged 31.vii.2014, D.L. Miller, originally from CHINA, Jilin (Jingyuetan Forest Park, Changchun), 2008, T. Zhao, from eggs of Agrilus planipennis [11 ♀, UCRC]; 4-8th-generation progeny, emerged 10.viii.2014, D.L. Miller, originally from CHINA, Jilin (Jingyuetan Forest Park, Changchun), 2009, T. Zhao, from eggs of Agrilus planipennis [16 ♀, UCRC]; 9th-generation progeny, emerged 18.vii.2014, D.L. Miller, originally from CHINA, Jilin (Jingyuetan Forest Park, Changchun), 2008, T. Zhao, from eggs of Agrilus planipennis [11 ♀, UCRC].

Distribution.

China ( Zhang et al. 2005; Liu et al. 2007); USA (introduced): Indiana, Maryland, Michigan, New York, Ohio, and Pennsylvania, as of March 2015 ( Abell et al. 2014; Bauer et al. in press).

Host.

Agrilus planipennis Fairmaire.

Comments.

Oobius agrili is a solitary thelytokous egg parasitoid of Agrilus planipennis , discovered in 2004 during foreign exploration for natural enemies in northeast China ( Zhang et al. 2005; Liu et al. 2007; Trjapitzin and Volkovitsh 2011). Adults Oobius agrili were reared from eggs at the USDA Forest Service Northern Research Station laboratory in East Lansing, Michigan, USA. Rearing stock for this colony originated from parasitized Agrilus planipennis eggs collected from Fraxinus pennsylvanica trees in Jingyuetan Forest Park, Changchun, Jilin Province, China in 2004-2009. In 2007, Oobius agrili introductions began in Michigan, USA, for classical biological control of Agrilus planipennis . As of fall 2014, releases of Oobius agrili had expanded to 19 states ( Bauer et al. in press). Abell et al. (2014) reported parasitism of Agrilus planipennis eggs averaged approximately 20% in 2012-2013 at some sites where Oobius agrili was established, however, more studies are needed to assess the impact of Oobius agrili and other Agrilus planipennis biocontrol agents on ash recovery in the USA. Since 2010, stock cultures of Oobius agrili have been provided to the USDA Animal and Plant Health Inspection Service Emerald Ash Borer Biocontrol Facility, Brighton, Michigan, USA, for mass-rearing and releasing as a biocontrol agent of Agrilus planipennis in infested regions of the USA ( Mapbiocontrol 2014). To distinguish Oobius agrili from the known native and the other introduced Oobius species, we provide illustrations of its metatarsus (Fig. 1), female antenna (Fig. 2), lateral habitus of the female (Fig. 3), and base of the forewing (Fig. 4).