Author Description

Megaspore assemblages of Middle to Upper Triassic age from the Alpine and German realm are described. The stratigraphic value of megaspores and the feasibility of supra-regional correlations are demonstrated. Investigations in the Dolomites of Southern Tyrol (Italy), comprising Wengen Formation, Cassian Formation and Raibl Group with a stratigraphic range from Longobardian (Upper Ladinian) to Julian (Middle Carnian) Substage, revealed a constant, individual-rich megaspore content. In the Longobardian Substage a total of 22 megaspore species is present. The Longobardian-Cordevolian boundary is marked by a decrease in megaspore diversity, caused by climatic and environmental changes. Out of 22 species known in the Longobardian only six species persist in the Cordevolian Substage and only four species are indicated in the Julian Substage. This newly described megaspore assemblage is named Horstisporites selaginelloides-assemblage (Assoziation). Correlation with the Dijkstraisporites beutleri-megaspore assemblage of German Lettenkeuper (Longobardian) is possible for the Longobardian part of the Horstisporites selaginelloides-assemblage, based on some rare species common to both assemblages. Yet, concerning the widespread, typical species, the Horstisporites selaginelloides-assemblage shows a quite independent composition. Probably most of the individual-rich species are endemic in the volcanic and carbonatic islands of Southern Alpine Longobardian to Julian. The Dijkstraisporites beutleri-assemblage was investigated in Southern Germany (Lettenkeuper of Franconia and Baden-Württemberg) for the first time and fits well with the data so far known from the German Basin. 30 species of megaspores are described. The Dijkstraisporites beutleri-assemblage (German Lettenkeuper, Longobardian) differs markedly from the Narkisporites harrisi-assemblage of German Reed Sandstone (Schilfsandstein, Julian). Supplementary to existing data, samples from Franconian Reed Sandstone were inve