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The variegated caper bug Stenozygum coloratum Klug is common in the Middle East, where it is a minor agricultural pest. Recently, it was found that S. coloratum is an alternative host for the egg parasitoid Ooencyrtus pityocampae Mercet, an important natural enemy of the pine processionary moth Thaumetopoea wilkinsoni Tams, a major pest of pines. This discovery, coupled with the general lack of knowledge of S. coloratum, prompted the present study, which focused on seasonal activity of S. coloratum in Israeli pine forests, bidirectional interactions between the bug and its host the caper plant Capparis spp., and parasitism of its eggs. Stenozygum coloratum activity lasted mainly from May to October, and was followed by an adult winter diapause. Individuals formed large aggregations, causing early withering of plants and a shortening their annual growth periods. Reproductive activity peaked in August and ended in September. Egg parasitism rates increased throughout this period. Several Ooencyrtus spp., including known natural enemies of various pests, parasitized the eggs of S. coloratum and other associated pentatomids found on the caper plants. Thus, capers probably serve as a refuge for these potentially important egg parasitoids. The potential of caper plants and their fauna for biological control programmes is discussed.

Ooencyrtus spp. (Hymenoptera, Chalci doi dea, Encyrtidae) are important natural enemies of agricultural and forest insect pests, and are distributed worldwide. Their reduced dimensions, highly variable morphological characters and possible effect of wide host range and abiotic factors, make correct identification at the species level particularly difficult. This paper combined molecular, morphological, and biological data to characterize a group of Ooencyrtus spp. emerging from the eggs of the variegated caper bug, Stenozygum coloratura in the east Mediterranean area. COI and ITS2 sequencing revealed the presence of six and five divergent clades, respectively. Three clades were identified as Ooencyrtus telenomicida, Ooencyrtus pityocampae and O. pistaciae. Two clades represent new species which are here described and named Ooencyrtus zoeae and Ooencyrtus mevalbelus. These features were combined with reliable morphological characters to facilitate the separation of these species. A dichotomous key and a new synonymy are proposed. Ooencyrtus pistaciae had two distinct COI clades but only one ITS2 Glade. Crossbreeding trials that included Ooencyrtus telenomicida, Ooencyrtus melvabelus sp. nov. and Ooencyrtus zoeae sp. nov. confirmed their reproductive isolation. COI sequences showed 0-0.8% and 4-9% within and between-species genetic differences, respectively. ITS2 showed 0.4-5.9% genetic differences between species, with no genetic differences within species. Haplotype diversity of Israeli and Turkish populations of the various species was 0-0.98 and was particularly low in Ooencyrtus pityocampae, whose Israeli population showed no diversity. The discovery of the Ooencyrtus spp. on the eggs of the caper bug, and their abundance support the idea that the bug can be used as an alternative host for augmentation of populations of these parasitoids in agricultural and forestry systems.