Notes on two nests of Pterocheilus phaleratus (Panzer, 1797), with new records of its prey (Hymenoptera: Vespidae: Eumeninae)

Two complete nests of Pterocheilus phaleratus (Panzer, 1797) were described from the north-eastern edge of the Pomeranian Flying Club in Toruń (northern Poland). Both nests were built in sandy terrain on a sloping surface (about 20°). The nests consists of a 5 cm long main burrow with a single cell. Digging and backfilling the nest involves carrying fine gravel in the mandibles. Females transported prey at a frequency of 6 to 12 minutes. The cell contained 25 larvae from the Tortricidae family (Acleris spp.). Metopia cf. argyrocephala (Meigen, 1824) (Diptera: Sarcophagidae) was observed following the female into the nest, but specimens of this species were not excavated from the cell.