The ferns of the Middle Triassic flora from Thale (Germany)

摘要

This is the third modern day paper on the Middle Triassic flora from Thale to be pub-lished, dealing with the ferns. Two species belong to the genus Asterotheca; Asterotheca merianii (BRONGNIART) STUR is one of the most common elements in the flora, while Asterotheca thalensis n. sp. is rarer in the assemblage. Both species yielded in situ round, pseudomonolete granulate spores. Danaeopsis marantacea (PRESL in STERNBERG) SCHIMPER is the most common fern in the Thale flora; for the first time in situ spores from this species are described. Rhacophyllum crispatum (MUNSTER in STERNBERG) n. comb. might be the aphleboid structure belonging to Danaeopsis marantacea. Todites gaillardotii (BRONGNIART) n. comb. is here described for the first time from the Erfurt Formation (Ladinian) of Germany. Moreover, its in situ spores are documented as well. Neuropteridium grandi-folium (SCHIMPER et MOUGEOT) COMPTER is just a rare element in this flora. Clathropteris meniscioides BRONGNIART and Phlebopteris sp. from Thale are earliest representatives of these genera known so far; all three species are represented only by sterile frond fragments. Cladophlebis remota (PRESL) VAN KONIJNENBURG-VAN CITTERT et al. is relatively rare, while Cladophlebis leuthardtii LEONARDI is very rare in this flora; fertile frond fragments are still missing for both species. For the first time Sphenopteris schoenleiniana (BRONGNIART) PRESL in STERNBERG is represented by sterile and fertile material in the Germanic Basin. Sphenopteris vel Cladophlebis sp. A might be shade leaves of Sphe-nopteris schoenleiniana. Chiropteris lacerata (QUENSTEDT) RUBLE VON LILIENSTERN is a very rare ele-ment in this flora and only represented by sterile frond fragments, in contrast to Symopteris rumpfii (SCHENK) KUSTATSCHER et al. The latter yielded in situ spores (round, trilete, smooth).