Parasitoid wasps diversity (Hymenoptera: Ichneumonidae) in diverse habitats of northeastern Iran

Abstract

The Ichneumonidae, one of the largest insect families, includes beneficial insects parasitizing several pests. Due to the geographic and climatic varability of Iran, a great Ichneumonidae diversity may be expected, but our knowledge about fauna and biodiversity of this family in Iran is still insufficient, with only a few sporadic biodiversity studies on Iranian ichneumonids. This paper examines the alpha diversity, species evenness, species richness and beta diversity of the Ichneumonid parasitoid wasp assemblages in Golestan Province, northeastern Iran with an emphasis on the two largest Ichneumonid subfamilies: Cryptinae and Ichneumoninae. The spatial diversity of Ichneumonidae in two consecutive years was studied in three habitats: forest, rangeland and orchards. A total of 336 specimens representing 62 genera and 97 species were collected and identified. The forest sites (Shast kalate and Tuskestan) and rangeland sites (Chahar bagh and Souz javal) were found to be more diverse than orchard sites (Kordkuy and Garmabdasht), but the lowest species evenness was observed in the latter. The highest species richness was found in rangeland, the highest similarity between the two forest sites, and the lowest similarity between Kordkuy (orchard) and Chaharbagh (rangeland). Of all individuals collected, 32.7% and 67.3% were female and male, respectively. The species richness and abundance of parasitoid wasp species yielded from the relatively small sample area indicate that there are many species in Iran that still remain to be discovered. In total, the use of parasitoid Hymenoptera, as potential bioindicators, provide a useful and practicable monitoring tool for tracking and evaluating changes in various ecosystems and reflecting environmental conditions.