First Records of the Pseudoscorpion Microbisium suecicum Lohmander, 1945 in Denmark with Notes on M. brevifemoratum (Ellingsen, 1903)

摘要

I work as a biologist for the Ministry of the Environment in Denmark. My primary responsibilities include mapping habitat types and monitoring Annex species listed in the EC Habitats Directive. This includes performing surveys of the narrow-mouthed whorl snail, Vertigo angustior (Jeffreys, 1830), a species which occupies different habitats, but is most frequently found living in beach ridge communities and coastal calcareous grasslands. Searching for this species involves pulling up grasses and sieving the root balls over a tray (Fig. I). Grass species investigated are Arrhenatherum elatius (False oat-grass), Festuca rubra (Red fescue) and Festuca arundinacea (Tall fescue). Using this method at Brakor, Horsens Fiord (an estuary in Central Denmark) my attention was caught by some very small pseudoscorpions moving in the tray. Looking closer with my lens I noted that the fingers of the pedipalps were short which excluded conspecificity with Neobisium carcinoides (Hermann, 1804). Considering the closeproximity to the coast I considered they might be N. maritimum (Leach, 1812), a species as yet unrecorded from Denmark. So I searched harder, hoping to find adultsbut all specimens found were small. Later, when inspecting the specimens under the stereomicroscope I realised that the specimens at hand were Microbisium suecicum Lohmander, 1945 (Figs. 2, 3) and that many specimens collected were adults despite their small size.