Notes on mid-Cretaceous †Pangusyndicus and its relatives, with description of †Loeblitoides gen. nov. and a †Nuegua-like new species (Coleoptera: Staphylinidae: Scydmaeninae)

Abstract

Two new species of Cenomanian Glandulariini are described, based on inclusions in Burmese amber: †Loeblitoides separatus gen. et sp. nov., and †Pangusyndicus longirostris sp. nov. A new specimen of an unnamed species of †Nuegua Yin et al. is recorded from the same deposit and illustrated for comparative purposes. †Loeblitoides is morphologically close to †Pangusyndicus, but has more plesiomorphic antennae, with the antennomere 11 distinctly smaller than 10, but fully demarcated by a constriction (antennomere 10 is not subcylindrical as in †Pangusyndicus, but fusiform). †Pangusyndicus longirostris, in turn, is unusual in having an elongated pre-ocular region of the head, resembling the condition known so far only in †Nuegua. Morphological affinities between these genera strongly suggest their close relationships. The previously postulated hypothesis of a close relationship between †Pangusyndicus and the extant Syndicus (and its closest relatives) is discussed as poorly supported, as these taxa, despite having similar antennal structure, differ in many important characters. In order to verify this issue, much dense taxon sampling (i.e., inclusion of at least most of extant genera and subgenera of Glandulariini) is required, as this is the largest and taxonomically most challenging tribe of Scydmaeninae, with still largely unknown relationships between extant taxa.