Lepidodendron jaschei A. ROEM., 1866

Cleal, Christopher J., Strullu-Derrien, Christine & Spencer, Alan R. T., 2024, Early Coal Swamp Vegetation From The Serpukhovian Lower Clackmannan Group Of Scotland, Fossil Imprint 80 (1), pp. 35-67 : 40

Lepidodendron jaschei A. ROEM., 1866

Text-fig. 3c,d

1866 Lepidodendron jaschei A. ROEM. , p. 213, pl. 35, fig. 6.

1885 Lepidodendron lossenii C.E. WEISS , p. 169, pl. 6, figs 6, 7.

1964 Lepidodendron jaschei A. ROEM. ; Crookall, pl. 64, figs 1, 2, pl. 69, figs 3–7.

1964 Lepidodendron lossenii C.E. WEISS ; Crookall, pl. 63, figs 3, 4.

1964 Lepidodendron cf. nathorstii KIDST. ; Crookall, pl. 66, fig. 1. 2021 Lepidodendron cf. nathorstii KIDST. ; Strullu-Derrien et al.,

fig. 3C.

D e s c r i p t i o n. Leaf cushions helically-arranged, sometimes laterally contiguous, sometimes separated by prominent 1–2 mm wide inter-cushion areas. Cushions subrhomboidal, slender, straight, 15–20 mm long, 3 mm wide, with narrow, thread-like prolongations at upper and lower ends. Round to laterally oval leaf scar located just above middle of cushion, showing clear vascular and two foliar parichnos cicatrixes. Cushion surfaces both above and below scar have prominent lateral ridges, but no parichnos visible below scar. Ligule pit visible above scar.

R e m a r k s. These distinctive, slender leaf cushions have often been referred to two separate fossil-species depending on whether the cushions are laterally contiguous ( L. lossenii ) or are separated by a wide inter-cushion area ( L. jaschei ). As pointed out by Potonié (1901), however, the types of these two species originated from the same locality (Kammerberg, Harz, Germany), and the two morphologies of stem are regularly found associated, and it is likely that they merely represent different growth stages of the same stems.

Similar fragments from the Maine-et-Loire flora were reported by Strullu-Derrien et al. (2021) and provisionally named L. cf. nathorstii KIDST. However , having now had the opportunity to examine the more extensive material from the lower Clackmannan Group, we now regard these French specimens as being conspecific with L. jaschei .

The unillustrated record of Lepidodendron spetsbergense NATH. from the Upper Limestone Formation of New Braidbar Quarry ( Kidston 1901) probably represents L. jaschei .

O c c u r r e n c e s. Mainly the upper Limestone Coal Formation, notably the Stripeside and Woodyett Pits, Denny, Stirlingshire; also from below the Orchard Limestone (Upper Limestone Formation).

Figures

Text-fig. 3. a–b: Lepidodendron veltheimii STERNB. a: Specimen showing larger leaf cushions; New Braidbar Quarry, Giffnock, East Renfrewshire; belowOrchardLimestone, Upper LimestoneFormation;BGS Kidst.248. b: Specimenshowingsmaller cushions;No 1 Pit, Polmaise Colliery, Fallin, Stirlingshire; Knott Coal, Limestone Coal Formation; BGS Kidst.5115. c–d: Lepidodendron jaschei J.ROEM. c: Specimen showing prominent intercushion areas; Woodyett Pit, Denny, Stirlingshire; above Blackband Ironstone,