Paratatarina, Vasilevskaya, 1972

Pott, Christian, 2014, The Upper Triassic flora of Svalbard, Acta Palaeontologica Polonica 59 (3), pp. 709-740 : 722-724

Paratatarina ptchelinae Vasilevskaya, 1972

Fig. 5A–O.

1972 Paratatarina ptchelinae ; Vasilevskaya 1972: 44, pls. 6: 5–8; 7: 1–5; 8: 1–6.

1972 Paratatarina spetsbergensis ; Vasilevskaya 1972: 44, pls. 9: 1a, 2–5, 6a, 7; 10: 1a, 2–9; 16: 2b; 17: 3c.

1972 Paratatarina sp. ; Vasilevskaya 1972: 46, pl. 11: 1–7.

1983 Paratatarina korchinskae ; Vasilevskaya 1983: 145, pls. 1: 3–5; 2: 1–3; 3: 1, 2.

Material.— Spitsbergen: Bertilryggen ( NRM S080252, S080253); Fleur de Lyshamna ( NRM S080080–S080085, S080095–S080102); Hyrnefjellet ( VSEGEI 10979-26, 10979-28, 10979-40–10979-49, 10979-76, 10979-90, 10979-91); Wimanfjellet ( VSEGEI 10979-12); Trehøgdene NRM S151684); Teistberget ( VSEGEI 10979-03). Barentsøya: Schweinfurthberget ( VSEGEI 10979-54). Edgeøya: Kapp Lee ( NRM S080187, S080188, S080191, S080193, S080197–S080199, S080202–S080206, S080208, S080210, S080212, S080216, S080218, S080223, S080229, S080232, S080235, S080236, S080238–S080240; VSEGEI 10979- 24, 10979-25, 10979-50–10979-53, 10979-92, 10979-93); Kapp Pechuel Lösche/Lindemanberget ( VSEGEI 10979- 37–10979-39). Hopen: Kollerfjellet (? VSEGEI 3/12163– 9/12163). Carnian (Upper Triassic).

Description.— Paratatarina ptchelinae is characterised by long, slender, fusiform leaves (e.g., Fig. 5B 2, J–L) whose largest representative is 291 mm long and 28 mm wide, but typical leaves only reach 150–200 mm long and 20 mm wide. The lamina tapers straight towards the base and the apex reaching its full width only in the middle fifth of the leaf (e.g., Fig. 5J). The leaf base is typically less than 4 mm wide (Fig. 5D, G). Leaf apices are acute and most are finely pointed (Fig. 5A, B 1, F 1, K); the lamina appears slightly frayed towards the leaf apex in most specimens. This may point to a very delicate lamina between the veins. Leaves are usually preserved with a slightly curved midvein and lamina (Fig. 5A, F 2, G). The central midvein (Fig. 5G, O) gives off fine secondary veins at regular intervals and at acute angles <15° (usually 4–10°), vein density is up to 20 veins/cm. Epidermal details are known from the type specimen ( Vasilevskaya 1972) and from P. korchinskae Vasilevskaya, 1983 ( Vasilevskaya 1983). The latter is here also regarded to be conspecific with P. ptchelinae (see Vasilevskaya 1972, 1983, for details).

A few specimens from the NRM collections provided cuticles serving at least for comparison and a rough description. Both abaxial and adaxial cuticles appear to be identical with one of both being slightly more strongly cutinised. Cuticles are robust; costal and intercostal fields are well distinguished; cells over the veins are elongate and slender, pointed, and arranged in rows parallel to the vein course; cells of intercostal fields are typically isodiametric or, in rare cases, slightly elongate, usually trapezoid and unordered, they are of similar shape to the subsidiary cells of the stomata but less cutinised; stomata are scattered at regular distances along one or two rows in the intercostal fields, surrounded by a ring of typically five (rarely four or six) trapezoid subsidiary cells that are more strongly cutinised than the surrounding epidermal cells. Each subsidiary cell cuticle is thickened towards the pit mouth and extends into a single solid papilla overarching the pit. Guard cells are deeply sunken but barely preserved. Anticlinal cell walls are straight with no ornamentation; in some specimens, periclinal cell walls show central cuticular thickenings (cf. Vasilevskaya 1972).

Remarks.— Some of the leaves here assigned to Paratatarina ptchelinae show almost parallel leaf margins as opposed to the tapering lamina in most specimens, and others have an acutely rounded apex as opposed to the pointed apex in most specimens. Attempts to sort the leaves into different “groups” based on lamina shape failed and thus, all are considered conspecific.No separation between leaves assigned to Paratatarina ptchelinae , P. spetsbergensis and Paratatarina sp. from Schweinfurthberget by Vasilevskaya (1972) could be achieved, and thus, the latter are here considered conspecific with P. ptchelinae . Vasilevskaya (1972) separated P. ptchelinae only by the presence of epidermal details from P. spetsbergensis . However, all specimens are macromorpho-

Fig. 5. Pteridosperm Paratatarina ptchelinae Vasilevskaya, 1972 from the Carnian (Upper Triassic) strata of Svalbard. A. VSEGEI 10979-45, from → Hyrnefjellet. B. NRM S080239-01, from Kapp Lee, different leaves on same specimen (B 1, B 2). C. VSEGEI 10979-48, from Hyrnefjellet. D. VSEGEI 10979-28, from Hyrnefjellet, note the slender leaf base (arrowhead). E. NRM S080236-01, from Kapp Lee. F. VSEGEI 10979-42 from Hyrnefjellet F 1), detail of venation (F 2). G. VSEGEI 4/12163, from Kollerfjellet, cf. Vasilevskaya (1983: pl. 1: 4), note slender leaf base and midvein (arrowheads).

H. VSEGEI 10979-54, from Schweinfurthberget. I. NRM S080082, from Fleur de Lyshamna, below the Pterophyllum layer. J. NRM S080080, from Fleur de Lyshamna, below the Pterophyllum layer. K. NRM S080102, from Fleur de Lyshamna, below the Pterophyllum layer, two different light angles (K 1, K 2) to highlight venation (arrowheads). L. NRM S080253, from Bertilryggen, note the rounded apex (arrowhead). M. NRM S080205-01, from Kapp Lee.

N. VSEGEI 10979-40, from Hyrnefjellet. O. VSEGEI 10979-49, from Hyrnefjellet, midvein arrowed. Scale bars 10 mm.

logically very similar and epidermal details documented for P. spetsbergensis reveal that the differences are minor and likely represent environmentally influenced variations. Paratatarina ptchelinae is comparatively common in the Upper Triassic flora from Svalbard and has been found at several localities. It is a very distinctive species and can only be mistaken for Arberophyllum species (see below). One specimen, identified as that illustrated in Vasilevskaya (1983: pl. 1: 4; Paratatarina korchinskae ), has an epidermal anatomy very similar to leaves of P. spetsbergensis . Thus, P. korchinskae is here also regarded as conspecific with P. ptchelinae .

Leaves occurring in a separate layer that was termed “un- der Pteropyllum -lagret” [“below the Pterophyllum layer”] by Alfred G. Nathorst and Johan G. Andersson when they collected the specimens at Fleur de Lyshamna (e.g., Fig. 5I– K) are here also assigned to Paratatarina ptchelinae based on macromorphological agreement (specimens S080080– S080085, S080095–S080102).

Geographic and stratigraphic range.— Svalbard; Carnian.