Dialipsis villahermosae Humala & Selfa n. sp. (Hymenoptera: Ichneumonidae), the second European species of the genus,with biological notes and a key of Palaearctic species

The small genus Dialipsis Förster 1869 (Hymenoptera: Ichneumonidae) includes two known species, of which one is common in Central and Northern Europe. Here we describe the male and female of a new species, Dialipsis villahermosae Humala & Selfa, which was reared from mushrooms collected in Eastern Spain. The host fungus gnat, Mycetophila blanda Winnertz, is a new record for the whole genus, while the rate of parasitism seems very low. Based on environmental data of the collection localities and data available for other two species it is suggested that Dialipsis species occur preferably in cool temperatures habitats. A key of identification of the two known Palaearctic species is provided. D. villahermosae n. sp. differs from D. exilis Förster 1871 in the morphology of the first tergite, referred to the presence of dorsal keels and angle between petiole and postpetiole, and in the convexity of temples.