Morphological and Molecular Methods in Identiication of Aphidius transcaspicus Telenga (Hym: Braconidae: Aphidiinae) Parasitoid of Hyalopterus spp. (Hom: Aphididae) with Additional Data on Aphidiinae Phylogeny Najme JAFARI AHMADABADI 1 Javad KARIMI 1 Mehdi MODARRES AWAL 1 Ehsan RAKHSHANI 2 1.Department of Plant Protection, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, IRAN, e-mails: sn.jafari@yahoo.com; jkb@um.ac.ir; ModarresAwal@yahoo.com 2. Department of Plant Protection, College of Agriculture, University of Zabol, Zabol, IRAN, e-mail: rakhshani@uoz.ac.ir ABSTRACT During 2009-2010, aphid parasitoid wasps (Hymenoptera: Braconidae: Aphidiinae) on stone fruit trees were investigated in Khorasan Razavi province, North East of Iran. In this survey, eight species from six genera, were reared from 26 associations (Aphid-host plant-parasitoid) in different localities in Khorasan Razavi province. Aphidius transcaspicus (62%) was the most abundant species of aphid parasitoids, in strict association with Hyalopterus spp. ITS2 rDNA sequence analyses conirmed classical studies. In phylogenetic analyses, our specimen, A. transcaspicus Mashhad1, made a single clade with other populations of this species. A. transcaspicus showed a good control potential on Hyalopterus pruni Geoffroy (Hom: Aphididae) on plum and apricot. So it can be used as a biocontrol agent against the mealy plum aphid in Khorasan Razavi geographical climates. Key words: Aphidius transcaspicus, Hyalopterus pruni, ITS2, Iran. INTRODUCTION Aphidiinae are solitary obligatory endoparasitoids of aphids and many species of them have been considered as potential biocontrol agents (Stary 1970). The genera Aphidius Nees is one of the most diverse taxa within the subfamily Aphidiinae (Tomanovic et al., 2007). In terms of systematics, Aphidius is a dificult genus (Mescheloff and Rosen, 1990). In some species, aphid host knowledge is helpful in identiication, some of the morphological characters used for identiication may also vary (environmentally- induced variations) (Pungerl, 1986). In Aphidius transcaspicus, geographical variability between populations of this species was indicated (Lozier et al., 2009). There has been some uncertainty surrounding the taxonomic status of Aphidius transcaspicus. It was irst described by Telenga (1958) from Uzbekistan. Stary (1975) considered Aphidius transcaspicus as synonymous with Aphidius colemani and again separated J. Entomol. Res. Soc., 13(2): 91-103, 2011 ISSN:1302-0250