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A new locality of Euonymus verrucosus Scop. has been found in the eastern part of the Wzgórza Trzebnickie Hills, near Malerzów village. The species is critically endangered in Lower Silesia and the only locality could be threatened by forest management.
A new locality of Diphasiastrum complanatum has been found in the eastern part of Twardogóra Hills, near Domasławice village. The species is vulnerable in Lower Silesia, but this locality is not endangered as yet. Possibilities of a protection of Diphasiastrum complanatum site from the viewpoint of a forest industry have been considered in this paper.
This paper presents a new locality of Iris sibirica L. in Lower Silesia. It presents current state of the stand and draws attention to threats and possibilities of its protection and preservation.
The paper presents the research on the distribution of endangered and protected species of the vascular flora of the Równina Olenicka Plain and the western part of the Trzebnickie Hills. It is the supplement of the nature stocktaking carried out within the administrative districts of the region during the years 1991 1993 and is pointing out the need for further research in order to expand the knowledge of this topic. As a result of the field research 34 endangered and protected plant species found on 173 localities were noted. Among them 26 species on 161 sites are protected by law and 24 species on 113 localities have different threat categories in Lower Silesia. Two species Osmunda regalis L. and Leucojum vernum L. are listed in the ,,Red list of plants and fungi in Poland (Mirek i in. 2006).
A new locality of Gladiolus imbricatus L. has been found in the eastern part of Wzgórza Trzebnickie Hills, between Grochowo and Czeszów villages. The species is vulnerable to extinction in Lower Silesia region and the locality in question could be threatened from different factors.
We report cyrtocrinid (Crinoidea) ossicles from the Rhaetian (Late Triassic) of the Tatra Mountains (southern Poland). The columnals are high, the facets are covered with thick crenulae and the latera are concave. Such features of symplectial articulation and latera distinguish them from the columnals of other Triassic crinoids (i.e., millericrinids and encrinids) and therefore we consider they belong to Cyrtocrinida. The oldest representatives of cyrtocrinids were known from the Early Jurassic, therefore the presented material constitutes the oldest world record of these crinoids to date. We speculate that perturbations related to the global mid−Carnian extinction combined with predation intensity observed in the Middle– Late Triassic have been involved in early origin of Cyrtocrinida.
Calcite isocrinid ossicles from the Middle Jurassic (Bathonian) clays in Gnaszyn (central Poland) show perfectly preserved micro− and nanostructural details typical of diagenetically unaltered echinoderm skeleton. Stereom pores are filled with ferroan calcite cements that sealed off the skeleton from diagenetic fluids and prevented structural and geochemical alteration. In contrast with high−Mg calcite skeleton of modern, tropical echinoderms, the fossil crinoid ossicles from Gnaszyn contain only 5.0–5.3 mole% of MgCO₃. This low Mg content can be a result of either a low temperature environment (ca. 10℃) and/or low Mg/Ca seawater ratio. Both conditions have been proposed for the Middle Jurassic marine environment. Occurrence of Mg−enriched central region of stereom bars of Jurassic columnal ossicle of Chariocrinus andreae is consistent with the concept of magnesium ions involvement in earliest growth phases of calcium carbonate biominerals.
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