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During systematic surveys of groundwater snails in Slovakia, Hungary and Bosnia and Hercegovina two new species of the genus Hauffenia, H. lozekiana sp. nov. from a single locality in Slovakia, and H. steffeki sp. nov. with a small range in Bosnia and Hercegovina were discovered and are here described based on shell morphology, anatomy and DNA sequence data (COI, 16S rRNA, ITS2). The discovery of H. steffeki sp. nov. extends the range of the genus considerably towards the south. Hauffenia lozekiana sp. nov. appears to be a relict surviving within the range of the today widely distributed H. kissdalmae. Based on a time tree, we developed a scenario for the origin and diversification of the genus. The ancestor probably evolved in the Miocene on the Balkans and with the gradual desiccation of the Paratethys and its remnant water bodies diversified towards the north. Karstic and in particular alluvial connectivities together with changing courses of paleo-rivers probably played an important role for dispersal. Ecological observations suggest that the phreatic rhizosphere, the delicate net of tree rootlets and their exudates, are important for the existence of these groundwater snails.
Most fossil feather stars are known only from the centrodorsal often connected to the radial circlet. This is the case for Discometra rhodanica (Fontannes, 1877), the type species of the genus Discometra, collected from the Late Burdigalian of the Miocene Rhône-Provence basin (southeastern France). The quarries operating in this area have exposed layers from the Late Burdigalian on the northern fl ank of the Lubéron anticline near Ménerbes (basin of Apt, Vaucluse, southeastern France). These layers contain exceptionally well-preserved echinoderms, among which are three specimens of a feather star with cirri and arms still connected to the centrodorsal. They are attributed to a new species: Discometraluberonensis sp. nov. (Himerometridae). The number of arms can reach 60, as in extant species of the genus Himerometra, but the pattern of arm divisions is closer to that of the genus Heterometra, which has no more than 45 arms in extant species. Discometra luberonensis sp. nov. diff ers from D. rhodanica by the characters of its centrodorsal. Here we redescribe the centrodorsal and radial circlets of D. rhodanica based on previously and newly collected specimens. We designate a neotype for D. rhodanica, because the holotype is considered lost. Affi nities between Discometra, Himerometraand Heterometra are discussed.