Ant-like stone beetles (Coleoptera: Scydmaenidae) include more than 4,850 described species in about 90 genera maintained as a separate cosmopolitan family since 1815. Recent authors have hypothesised that Scydmaenidae might be rooted deep inside rove-beetles (Staphylinidae). To test this hypothesis we analysed 206 parsimoniously informative larval and adult morphological characters scored for 38 taxa. Strict consensus topologies from the shortest trees in all 12 analyses consistently placed Scydmaenidae as sister to (Steninae + Euaesthetinae) in a monophyletic Staphylinine Group (with or without Oxyporinae). The single fully resolved and most consistently supported topology maintains a monophyletic Staphylinine Group consisting of Oxyporinae + (Megalopsidiinae + (("Scydmaenidae" + (Steninae + Euaesthetinae)) + (Leptotyphlinae + (Pseudopsinae + (Paederinae + Staphylininae))))); Solierius lacks larval data and is ambiguously placed within the Group. Eight analyses of variably aligned 18S rDNA data for 93 members of Staphylinoidea under parsimony, neighbour-joining and Bayesian approaches were markedly inconsistent, although partly congruent with the Scydmaenidae + (Steninae + Euaesthetinae) hypothesis. Our results strongly suggest that ant-like stone beetles do not form an independent family, but are morphologically modified members of Staphylinidae and, consequently, should be treated as a 32nd recent subfamily within the megadiverse Staphylinidae sensu latissimo. Formal taxonomic acts are: Scydmaeninae Leach, 1815, status novus (= Scydmaenidae Leach, 1815); Scydmaenitae Leach, 1815, status novus (= Scydmaeninae Leach, 1815); Mastigitae Fleming, 1821, status novus (= Mastiginae Fleming, 1821); Hapsomelitae Poinar & Brown, 2004, status novus (= Hapsomelinae Poinar & Brown, 2004). The family Staphylinidae sensu latissimo becomes the largest in Coleoptera and in the whole of the Animal Kingdom, with 55,440 described species (extant plus extinct), thus surpassing Curculionidae with an estimated 51,000 described species.

The megadiverse subfamily Staphylininae traditionally belonged to the best-defined rove beetle taxa, but the advent of molecular phylogenetics in the last decade has brought turbulent changes to the group’s classification. Here, we reevaluate the internal relationships among the tribes of Staphylininae by implementing tree inference methods that suppress common sources of systematic error. In congruence with morphological data, and in contrast to some previous phylogenetic studies, we unambiguously recover Staphylininae and Paederinae as monophyletic in the traditional sense. We show that the recently proposed subfamily Platyprosopinae (Arrowinus and Platyprosopus) is a phylogenetic artefact and reinstate Arrowinus as a member of Arrowinini stat. res. and Platyprosopus as a member of Platyprosopini stat. res. We show that several recent changes to the internal classification of the subfamily are phylogenetically unjustified and systematically unnecessary. We, therefore, reestablish Platyprosopini, Staphylinini, and Xantholinini as tribes within Staphylininae (all stat. res.) and recognize Coomaniini as a tribe (stat. nov.) rather than subfamily. Consequently, the traditional ranks of the subtribes Acylophorina, Afroquediina, Amblyopinina, Antimerina, †Baltognathina, Cyrtoquediina, Erichsoniina, Hyptiomina, Indoquediina, Quediina, and Tanygnathinina are restored (all stat. res.). We review the current classification of Staphylininae and discuss sources of incongruence in multigene phylogenies.

Carrion beetles (Silphidae) and rove beetles (Staphylinidae, including Scaphidiinae, Pselaphinae and Scydmaeninae) form a well supported and exceptionally species-rich clade with nearly 58,000 described Recent species (of them Silphidae constitute0.3%). The presently accepted classification implies a sister-group relationship between these families. The enormous clade of Staphylinidae, if indeed monophyletic, has its basal-most dichotomies inadequately hypothesized. We analysed 240parsimony-informative larval and adult morphological characters for 34 terminals of carrion (3) and rove beetles (31) and rooted the obtained topologies on Neopelatops (Leiodidae). The most fully resolved topologies from the combined datasetconsistently suggest that carrion and rove beetles are indeed monophyletic sister-groups. Two ancient species-poor rovebeetle subfamilies (Apateticinae with two genera in the eastern Palaearctic, and the monogeneric Holarctic Trigonurinae)branch off as a clade from the rest of Staphylinidae, rather than with members of the Oxyteline Group. Subsequent dichotomies of the staphylinid main clade remain obscure. A newly redefined and monophyletic Oxyteline Group is formed byScaphidiinae + (Oxytelinae + Osoriinae + Piestinae), the last subfamily paraphyletic with respect to the previous two, which are monophyletic. The Oxyteline Group and the earlier detected monophyletic Omaliine and Staphylinine Groups form threemain subdivisions within the rove beetles. Their interrelationships, as well as those with the possibly monophyletic Tachyporine Group (which includes the mega-diverse Aleocharinae), form the main unresolved questions in basal Staphylinidaephylogeny.

Experimental research on beetle responses to removal of logging residues following clearcut harvesting in the boreal balsam fir forest of Quebec revealed severa

The first definitive fossil species of the rove beetle (Staphylinidae) subfamily Phloeocharinae is described and figured from a single individual preserved in Late Cretaceous (Turonian) amber from New Jersey. The species is representative of the extant genus Phloeocharis Mannerheim and is described as Phloeocharis agerata Chatzimanolis, Newton, and Engel, new species. The specimen was imaged using traditional light microscopy as well as synchrotron propagation phase contrast microtomography, permitting a detailed examination of otherwise difficult to observe features. Examination revealed remarkable homogeneity across many characters with those of extant relatives, highlighting considerable morphological stasis in the genus over the last 90 million years.