Morphological characterization of Ephedrus persicae biotypes (Hymenoptera: Braconidae: Aphidiinae) in the Palaearctic

Abstract

Ephedrus persicae Froggatt (Hymenoptera: Braconidae: Aphidiinae) represents a biologically complex parasitoid species group that parasitizes >150 aphid species worldwide, including many pests in different agroecosystems. Evidence from the host range indicated some taxonomic problems within this species-complex. Using classical and geometric morphometric approaches, we assessed the morphological differences among various E. persicae biotypes in the Palaearctic reared from 20 aphid hosts. We found that morphological variability of E. persicae biotypes was influenced by the host. Classical morphometric analysis indicated a conservative position of E. persicae biotypes in the Palaearctic. Our analysis showed that E. persicae biotypes reared from nonleaf-curling Aphis and leaf-curling Dysaphis aphid hosts have significant differences, but all other analyzed E. persicae biotypes have an intermediate position, making it impracticable to split the E. persicae group this way. However, geometric morphometrics used to analyze variation of wing shape showed better predictive ability. The high ratio of correctly assigned individuals based on the wing shape of E. persicae/Aphis viticis Ferrari, E. persicae/Brachycaudus klugkisti (Börner), and E. persicae/Tuberocephalus momonis (Matsumura) biotypes indicates that some host-specific adaptations occurred. The E. persicae/Hyadaphis foeniculi (Passerini) biotype is clearly separated along the CV2 canonical axis, exhibiting shorter and wider wings. on the basis of this result, we describe a new taxon - Ephedrus lonicerae n. sp. © 2009 Entomological Society of America.