Dictyophyllum exile ( Brauns, 1862 ) Nathorst, 1878a

Pott, Christian, 2014, The Upper Triassic flora of Svalbard, Acta Palaeontologica Polonica 59 (3), pp. 709-740 : 718

Dictyophyllum exile ( Brauns, 1862) Nathorst, 1878a

Fig. 4A.

1862 Camptopteris exilis ; Brauns 1862: 54, pl. 13: 11.

1878 Dictyophyllum exile Brauns ; Nathorst 1878a: 14, pl. 1: 9.

1878 Dictyophyllum exile Brauns ; Nathorst 1878b: 39, pl. 5: 7.

2009 Dictyophyllum exile ( Brauns 1862) Nathorst 1878 ; Schweitzer et al. 2009: 41, pl. 10: 1–3, text-fig. 7.

2011 Dictyophyllum exile (Brauns) Nathorst 1878 ; Pott and McLoughlin 2011: 1031, pl. 5: A–D.

Material.— Edgeøya: Kapp Lee ( NRM S 080220); Carnian Upper Triassic).

Description.— The Svalbard specimen shows two fragmentary sterile pinnae, 21 and 30 mm long and 10 mm wide (Fig. 4 A). The margins of the pinnae are strongly lobed; lobes are more arched and pointed than bluntly triangular. Each lobe has a prominent midvein that gives off a complex reticulum of subsidiary veins (Fig. 4 A).

Remarks.— Dictyophyllum exile is represented by two pinnae and some lamina fragments on one slab from Kapp Lee on Edgeøya. The fragments are identical to material from Scania, southern Sweden, figured by Nathorst (1878a, b) and Pott and McLoughlin (2011). Dictyophyllum exile is a typical Rhaetian species ( Pott and McLoughlin 2011) and it is possible that the specimen under study was collected ex situ on the beach and derives from a Rhaetian layer exposed higher on the cliffs. This taxon is readily confused with D. nathorstii Zeiller, 1903 , which is distinguished mostly by its basally adnate pinnae as opposed to the completely free pinnae in D. exile ( Schweitzer et al. 2009; Pott and McLoughlin 2011). However, this character is not useful if only isolated pinnae are preserved. Both species occur mainly in Rhaetian deposits and are commonly co-preserved.

Geographic and stratigraphic range.— Europe, Middle East; Norian–Middle Jurassic.