Sphenopteris sp.

Pott, Christian, 2014, The Upper Triassic flora of Svalbard, Acta Palaeontologica Polonica 59 (3), pp. 709-740 : 721

cf. Sphenopteris sp.

Fig. 4I.

Material.— Spitsbergen: Edlundfjellet (NRM S080263); Carnian (Upper Triassic).

Description.— One very small specimen from Edlundfjellet represents the apical part of a fern pinna/frond with 5–6 pinnule pairs that are sub-oppositely to alternately positioned (Fig. 4I). The preserved part is 10 mm long with individual pinnules 1.2–1.5 mm wide basally and reaching 3.1 μm long. Pinnules are inserted laterally by their whole basal width on a 0.3 mm wide rachis. A central vein is recognisable in each pinnule, but subsidiary veins are not distinct. Pinnule margins show some tendency towards lobation. The apical pinna is not preserved.

Remarks.— Among the studied collections, only this tiny specimen was found. Vasilevskaya (1972) did not mention or figure any comparable specimen.Assignment is equivocal due to its small size and incomplete venation details. Among the many Sphenopteris species, the typically Late Triassic Sphenopteris schoenleiniana (Brongniart, 1835) Presl in Sternberg, 1838 is very similar. The specimen from Edlundfjellet is among the lowest size range mentioned for this species by Kustatscher and Van Konijnenburg-van Cittert (2011), and is consequently interpreted as the tip of a pinna or, because the pinnae seem to show a tendency to dissect into third order pinnules, even a pinnule.