Vespa insolens Harris, 1782: 129 (type locality: England; type material destroyed). Synonymized by van der Vecht and Fischer, 1972: 108. Nomen oblitum.

Vespa antilope Panzer, 1798: 9 ([♀]; type locality: “ Austria ”; type material destroyed). Nomen protectum.

Odynerus pictus Curtis, 1826: 137, no. 2 (type locality: Great Britain and Ireland; type material in the Melbourne Museum, Melbourne, Australia). Synonymized by Blüthgen, 1938: 284.

DIAGNOSIS: The species can be distinguished from all other Ancistrocerus species by the following combination of characters: female clypeus about 1.15× as wide as long in frontal view, its apical margin slightly but distinctly emarginate (fig. 1A); male clypeus about 1.2× as wide as long in frontal view (fig. 1C); anterior angles of the pronotum obtuse in dorsal view; metapleuron and lateral surface of the propodeum shining, impunctate, without rugosity; inferior ridge of the propodeum well developed; sternum 2 in lateral view evenly convex, in ventral view without a longitudinal furrow at base; cuspis without an additional lobe below the base of the digitus, digitus large (figs. 2A, 2B); aedeagus in dorsal view with a broad bifurcate apex (fig. 2E), in lateral view evenly curved (fig. 2F); ventral lobe of the aedeagus in lateral view with a distinct sclerotized angle at base (fig. 2F).

DISTRIBUTION: Europe (all regions), Russia (all federal districts), Turkey, Afghanistan, Kyrgyzstan, Kazakhstan, Mongolia, China (northeast), Japan (Hokkaido, Honshu), India (Kashmir).

REMARKS: Van der Vecht and Fischer (1972) reported that the name Vespa insolens would be proposed for permanent rejection but we did not find the corresponding proposal. Yet, to the best of our knowledge, V. insolens has not been used as a valid name since 1899. On the other hand, the name A. antilope has been used as the presumed valid name for this taxon in far more than 25 works, published by far more than 10 authors in the immediately preceding 50 years and encompassing a span of far more than 10 years (see References). According to Article 23.9.1 of the ICZN (1999), A. antilope is the valid name for this taxon and is considered a nomen protectum, while V. insolens is assigned the status of nomen oblitum.