Composition, systematics, distribution and bionomics of the poorly known primarily Oriental genus Anchocerus Fauvel, 1905 is reviewed, with an annotated list and identification key provided for all 13 named species of the genus. The poorly known species from Papua New Guinea, A. punctus Last, 1980, A. similis Last, 1980 and A. wilhelmensis Last, 1980 are redescribed. Three new species, A. aparamerus sp.n. from Borneo, A. grandis sp.n. and A. thailandicus sp.n., both from Thailand are described. One species is transferred to Anchocerus from the genus Acylophorus Nordmann, 1837: Anchocerus tenuipes (Lea, 1929) comb. n., and also redescribed. Two species of Anchocerus are moved to Acylophorus: Acylophorus novaguinensis (Last, 1975) comb. n. and Acylophorus okasaensis (Last, 1975) comb. n. Morphological characters distinguishing the genera Anchocerus and Acylophorus are summarized. Type material was examined for all insufficiently known species.
A new species of the extinct rove beetle genus Hesterniasca Zhang, Wang & Xu, 1992 is described and illustrated on the basis of a well-preserved specimen from the Lower Cretaceous Yixian Formation at Huangbanjigou of Beipiao City, Liaoning Province, Northeastern China. Based on the examination of this new species that is preserved better than the type species of the genus, Hesterniasca is firmly placed in the recent subfamily Tachyporinae, tentatively in the recent tribe Tachyporini MacLeay, 1825. Arguments for the Early Cretaceous age of the Laiyang Formation in Shandong Province, Eastern China, from where the type species of the genus, Hesterniasca obesa Zhang, Wang & Xu, 1992, has been discovered are provided.
A remarkable extinct rove beetle, Megolisthaerus chinensis Solodovnikov & Yue, gen. et sp.n., from the Yixian Formation (some 125-121 million years ago) in China is described. The new taxon displays a very puzzling combination of morphological characters, some of which are insufficiently preserved for unambiguous interpretation. As a result, Megolisthaerus chinensis cannot be clearly assigned to any of the hitherto described subfamilies of Staphylinidae. Based on the evaluation of the available morphological characters, it seems to be either a member of, or closely related to, the recent subfamilies Olisthaerinae and Phloeocharinae, together forming a loosely defined lineage within the Tachyporine-group of subfamilies. Megolisthaerus chinensis is a remarkable species that shows that the phylogenetic structure of Staphylinidae in Early Cretaceous might have been significantly different from the one displayed by the recent fauna of this enormously diverse family. It is possible that Megolisthaerus manifests an extinct group of suprageneric rank that, naturally, cannot be classified within the current system of the family that is based on the study of recent lineages.
For the first time eggs, larvae and pupae obtained by rearing are described for Astrapaeus, a monotypic West Palearctic rove beetle genus of a puzzling phylogenetic position within the megadiverse tribe Staphylinini. Morphology of the immature stages of Astrapaeus ulmi is compared to that of other members of the tribe and discussed in a phylogenetic context. Contrary to conventional systematics and in accordance with recently developed phylogenetic hypotheses based on morphology of adults, larval morphology supports the non-Quediina affiliation of Astrapaeus. Eggs and pupae provided fewer characters with putative phylogenetic signal. Under laboratory conditions, a peculiar preference for isopod prey was observed for A. ulmi. However, this could not be evaluated in an evolutionary context because of the lack of data on the diet of this and related taxa in nature.