Integrative taxonomy of root aphid parasitoids from the genus Paralipsis (Hymenoptera, Braconidae, Aphidiinae) with description of new species

Abstract

Species from the genus Paralipsis are obligatory endoparasitoids of root aphids in the Palaearctic. It is known that these species are broadly distributed, parasitizing various aphid hosts and showing great biological and ecological diversity. On the other hand, this group of endoparasitoids is understudied and was thought to be represented by a single species in Europe, viz., Paralipsis enervis (Nees). However, recent description of two new species indicated the possibility of cryptic speciation and recognition of additional Paralipsis species in Europe. In this research, Paralipsis specimens collected during the last 60 years from eight European countries, as well as one sample from Morocco, were subjected to molecular and morphological characterization. Newly designed genus-specific degenerative primers successfully targeted short overlapping fragments of COI of the mitochondrial DNA. Molecular analyses showed clear separation of four independent lineages, two of which are the known species P. enervis and P. tibiator, while two new species are described here, viz., P. brachycaudi Tomanovic & Stary, sp. n. and P. rugosa Tomanovic & Stary, sp. n. No clear specialization of the taxa to a strict root aphid host has been determined. The recognized mitochondrial lineages were distinct one from another, but with a substantial within-lineage divergence rate, clearly indicating the complexity of this group of parasitoids, on which further research is required in order to clarify the factors triggering their genetic differentiation. We reviewed literature data and new records of Paralipsis enervis aphid host associations and distributions. A key for the identification of all known Paralipsis species is provided and illustrated.