Lycopsid megaspores from the Upper Triassic of Svalbard and their relationship to the floras and palaeoenvironments of northern Pangaea

Triassic megaspore assemblages from Svalbard, Arctic Norway, are described for the first time based on the analysis of the Upper Triassic (Carnian–Norian/Rhaetian) Kapp Toscana Group on the island of Hopen. Two megaspore zones are described: the late Carnian ‘Dijkstraisporites beutleri Zone’ (undifferentiated De Geerdalen Formation), and the Norian/Rhaetian ‘D. beutleri – Verrutriletes preutilis Zone’ (Svenskøya Formation). Megaspores are attributed to heterosporous lycopsids, and likely correspond to the microspore Aratrisporites, which was observed in palynological preparations. Megaspore occurrence was highest in delta-plain and associated with lake-mire deposits. However, their close association with marine microfossils suggests episodic marine influence, and is consistent with previous interpretations that some Triassic lycopsids occupied marginal marine habitats. The absence of megaspores in the overlying Hopen Member and Flatsalen Formation is likely related to a marine transgre...