Are subcortical rove beetles truly Holarctic? An integrative taxonomic revision of north temperate Quedionuchus (Coleoptera: Staphylinidae: Staphylininae)

Formation of the Holarctic Fauna: Dated molecular phylogenetic and biogeographic insights from the Quedius-lineage of Ground-Dwelling Rove Beetles (Coleoptera, Staphylinidae)

Although the Holarctic fauna has been explored for centuries, many questions on its formation are still unanswered. For example, i) what was the impact of the uplift of the Himalaya and Tibetan Plateau?, ii) what were the timings and climate of the faunal bridges connecting the Nearctic and Palearctic regions?, and iii) how did insect lineages respond to the late Paleogene global cooling and regional aridification? To answer these, we developed a phylogenetic dataset of 1229 nuclear loci for a total of 222 species of rove beetles (Staphylinidae) with emphasis in the tribe Quediini, especially Quedius-lineage and its subclade Quedius sensu stricto. Using eight fossils for calibrating molecular clock, we estimated divergence times and then analysed in BioGeoBEARS paleodistributions of the most recent common ancestor for each target lineage. For each species we generated climatic envelopes of the temperature and precipitation and mapped them across the phylogeny to explore evolutionary shifts. Our results suggest that the warm and humid Himalaya and Tibetan Plateau acted as an evolutionary cradle for the Quedius-lineage originating during the Oligocene from where, in the Early Miocene, the ancestor of the Quedius s. str. dispersed into the West Palearctic. With the climate cooling from the Mid Miocene onwards, new lineages within Quedius s. str. emerged and gradually expanded distributions across the Palearctic. In Late Miocene, a member of the group dispersed to the Nearctic region via Beringia before the closure of this land bridge 5.3 Ma. Paleogene global cooling and regional aridification largely shaped the current biogeographic pattern for Quedius s. str. species, many of them originating during the Pliocene and shifting or contracting their ranges during Pleistocene.

Sampling and curation of rove beetles (Insecta, Coleoptera, Staphylinidae) for comprehensive and DNA-grade collections to enhance biodiversity exploration in Northern Eurasia

Staphylinidae beetles form a major portion of terrestrial biodiversity globally and, in particular, in Northern Eurasia, a large area with a historically better known north temperate, subarctic and arctic biota. However, even here, rove beetles remain amongst the so-called "dark taxa" with a high fraction of taxonomically unknown lineage diversity. The propagation of DNA-based technologies in systematic entomology in recent decades has brought new opportunities for biodiversity exploration, true also for Staphylinidae. Simultaneously, new methods have revealed limitations of specimens sampled and curated by traditional practices, as existing legacy collections, whether institutional or private, unfortunately do not always qualify as a source of DNA-grade material. In addition, both legacy and newly-collected DNA-grade material of Staphylinidae remain highly biased towards Central Europe, a region with a traditionally well-developed scientific infrastructure and long-established culture for the maintenance of entomological collections. To increase the degree of biodiversity knowledge for our target organismal group across the globe, efficient sampling of DNA-grade material and, in particular, the development of comprehensive local collections in under-studied regions is highly desirable. To facilitate that, here we provide a practical guide for collecting and curation of Staphylinidae with a focus on capacity building for DNA-grade collections in Siberia and elsewhere in Northern Eurasia.

Integrative taxonomy of Nearctic and Palaearctic Aleocharinae: new species, synonymies, and records (Coleoptera, Staphylinidae)

A long tradition of separate Nearctic and Palaearctic taxonomic studies of the diverse aleocharine rove beetles (Coleoptera: Staphylinidae) has obscured the recognition of Holarctic species and detection of adventive species in both regions. Recently, integrated study of the two regions through detailed morphological comparisons and development of an authoritatively identified DNA barcode reference library has revealed the degree to which these two aleocharine faunas are interconnected, both naturally and through human activity. Here this approach is adopted to recognize new species, reveal Holarctic species, and recognize adventive species in both North America and Europe. The following new species are described: Isoglossatriangularis Klimaszewski, Brunke & Pentinsaari, sp. nov. from British Columbia; Gnypetaimpressicollis Klimaszewski, Brunke & Pentinsaari, sp. nov., from Ontario, Maryland and North Carolina; Aloconotapseudogregaria Klimaszewski, Brunke & Pentinsaari, sp. nov., from Ontario and Virginia; and Philhygrapseudolaevicollis Klimaszewski, Brunke & Pentinsaari, sp. nov. from eastern Canada. Dasygnypetavelata and Philhygraangusticauda are revealed to be Holarctic species, resulting in the following synonymies: Dasygnypetavelata (Erichson, 1839) = Gnypetaminuta Klimaszewski & Webster, 2008, syn. nov. and Philhygraangusticauda (Bernhauer, 1909) = Atheta (Philhygra) pinegensis Muona, 1983, syn. nov. The Nearctic species Hylotaochracea (and genus Hylota), Thecturotatenuissima, and Trichiusarobustula are newly reported from the Palaearctic region as adventive, resulting in the following synonymies: Hylotaochracea Casey, 1906 = Stichoglossa (Dexiogyia) forticornis Strand, 1939, syn. nov.; Thecturotatenuissima Casey, 1893 = Athetamarchii Dodero, 1922, syn. nov.; and Trichiusarobustula Casey, 1893 = T.immigrata Lohse, 1984, syn. nov. The Palaearctic species Amarocharaforticornis, Anomognathuscuspidatus, Oligotapumilio, and Parocyusarubicunda are newly confirmed from the Nearctic region as adventive, resulting in the following synonymies: Parocyusarubicunda (Erichson, 1837) = Chiloporaamericana Casey, 1906, syn. nov. and Anomognathuscuspidatus (Erichson, 1839) = Thecturaamericana Casey, 1893, syn. nov. The genus Dasygnypeta, sensu nov. is newly reported from North America, Paradilacra is newly reported from eastern North America, and Haploglossa is newly reported from Canada, resulting in the following synonymy: Paradilacradensissima (Bernhauer, 1909) = Gnypetasaccharina Klimaszewski & Webster, 2008, syn. nov. Native Cypheawallisi is newly reported from across Canada and C.curtula is removed from the Nearctic fauna. The status of both Gyrophaenaaffinis and Homalotaplana is uncertain but these species are no longer considered to be adventive in North America. Three new combinations are proposed: Dasygnypetabaranowskii (Klimaszewski, 2020) and D.nigrella (LeConte, 1863) (both from Gnypeta) and Mocytascopula (Casey, 1893) (from Acrotona). Dolosota Casey, 1910, syn. nov. (type species Eurypronotascopula Casey), currently a subgenus of Acrotona, is therefore synonymized with Mocyta Mulsant & Rey, 1874. Additionally, four new Canadian records and 18 new provincial and state records are reported.