Idiasta dichrocera Konigsmann, 1960 - Belg. sp. nov.

(Fig. 7)

BELGIUM: • 1 ♂; N51.130° E4.253°; vi/2021; J. Jacobs leg.; coll. KVA; pan trap (blue); K. van Achterberg det. • 1 ♀; N51.135° E4.251°; vii/2021; J. Jacobs leg.; coll. ADK; pan trap (yellow); F. Verheyde det. • 1 ♀; N51.125° E4.260°; viii/2021; J. Jacobs leg.; coll. KVA; pitfall trap; K. van Achterberg det. • 1 ♀; N51.135° E4.241°; viii/2021; J. Jacobs leg.; coll. ADK; pitfall trap; F. Verheyde det. [4 occ. (1 year), 4 roofs]

Remarks:

Originally, this species was reported as one of the more remarkable species of green roofs in the Netherlands (DRUKKER, VAN ACHTERBERG & DE BOER, 2019). Only after an additional specimen was collected of the “Erasmusschildwesp“, it became clear that both Dutch specimens (RMNH) belong to the very closely related I. picticornis (Ruthe, 1854) . The assumption in a key by FISCHER (2008) that I. dichrocera has both females with and without pale subapical part of the antenna is not explained. Therefore, there is no reason to accept such extreme variation without additional research.