Species delimitation in theAleochara fucicolaspecies complex (Coleoptera: Staphylinidae: Aleocharinae) and its phylogenetic relationships

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.

The tree that hides the forest: cryptic diversity and phylogenetic relationships in the Palaearctic vector Obsoletus/Scoticus Complex (Diptera: Ceratopogonidae) at the European level

Background

Culicoides obsoletus is an abundant and widely distributed Holarctic biting midge species, involved in the transmission of bluetongue virus (BTV) and Schmallenberg virus (SBV) to wild and domestic ruminants. Females of this vector species are often reported jointly with two morphologically very close species, C. scoticus and C. montanus, forming the Obsoletus/Scoticus Complex. Recently, cryptic diversity within C. obsoletus was reported in geographically distant sites. Clear delineation of species and characterization of genetic variability is mandatory to revise their taxonomic status and assess the vector role of each taxonomic entity. Our objectives were to characterize and map the cryptic diversity within the Obsoletus/Scoticus Complex.

Methods

Portion of the cox1 mitochondrial gene of 3763 individuals belonging to the Obsoletus/Scoticus Complex was sequenced. Populations from 20 countries along a Palaearctic Mediterranean transect covering Scandinavia to Canary islands (North to South) and Canary islands to Turkey (West to East) were included. Genetic diversity based on cox1 barcoding was supported by 16S rDNA mitochondrial gene sequences and a gene coding for ribosomal 28S rDNA. Species delimitation using a multi-marker methodology was used to revise the current taxonomic scheme of the Obsoletus/Scoticus Complex.

Results

Our analysis showed the existence of three phylogenetic clades (C. obsoletus clade O2, C. obsoletus clade dark and one not yet named and identified) within C. obsoletus. These analyses also revealed two intra-specific clades within C. scoticus and raised questions about the taxonomic status of C. montanus.

Conclusions

To our knowledge, our study provides the first genetic characterization of the Obsoletus/Scoticus Complex on a large geographical scale and allows a revision of the current taxonomic classification for an important group of vector species of livestock viruses in the Palaearctic region.

Molecular association and morphological characterisation of Himalopsyche larval types (Trichoptera, Rhyacophilidae)

Himalopsyche Banks, 1940 (Trichoptera, Rhyacophilidae) is a genus of caddisflies inhabiting mountain and alpine environments in Central and East Asia and the Nearctic. Of 53 known species, only five species have been described previously in the aquatic larval stage. We perform life stage association using three strategies (GMYC, PTP, and reciprocal monophyly) based on fragments of two molecular markers: the nuclear CAD, and the mitochondrial COI gene. A total of 525 individuals from across the range of Himalopsyche (Himalayas, Hengduan Shan, Tian Shan, South East Asia, Japan, and western North America) was analysed and 32 operational taxonomic units (OTUs) in our dataset delimited. Four distinct larval types of Himalopsyche are uncovered, and these are defined as the phryganea type, japonica type, tibetana type, and gigantea type and a comparative morphological characterisation of the larval types is presented. The larval types differ in a number of traits, most prominently in their gill configuration, as well as in other features such as setal configuration of the pronotum and presence/absence of accessory hooks of the anal prolegs.