Cladophlebis sp.

Kustatscher, Evelyn, Dellantonio, Elio & Van Konijnenburg-Van Cittert, Johanna H. A., 2014, The ferns of the late Ladinian, Middle Triassic flora from Monte Agnello, Dolomites, Italy, Acta Palaeontologica Polonica 59 (3), pp. 741-755 : 752

Cladophlebis sp.

Fig. 6B–E .

Material.— MGP 63/71, 194/87, 194/88, 194/89A–B, Monte Agnello, Dolomites, N-Italy, early late Ladinian.

Description.— The fronds are at least bipinnate. The fragments are up to 80 mm long and 55 mm wide (MGP 194/88; Fig. 6B ). The primary rachis is 3–5 mm thick. Pinnae arise suboppositely and at an acute angle (45–50°) from the rachis, but then curve slightly outwards. Pinnae fragments are up to 55 mm long and generally 10–12 mm wide; just in one case the pinnae fragments are broader (MGP 194/89A; Fig. 6E ). It could belong to a basal frond fragment. The rachis of the pinnae is 1–1.5 mm wide. The pinnules are lanceolate to slightly falcate with a rounded apex and a broad base. The pinnules are densely inserted alternately to suboppositely at an angle of 70–80°. The pinnules are 5–11 mm long and 2.5–4 mm wide (MGP 194/87; Fig. 6C ). The midrib is distinct. The secondary veins arise at an acute angle (c. 50°), bifurcate once halfway along the lamina and perhaps once again near the margin (MGP 63/71; Fig. 6D ).

Remarks.— These remains are very fragmentary and too badly preserved to be assigned to a new or established species. They resemble the Late Triassic species Cladophlebis remota (Presl, 1838) Van Konijnenburg-van Cittert, Van Konijnenburg-van Cittert, Kustatscher, and Wachtler, 2006, but in the latter species the pinnules are more closely inserted and the apex is acute. Cladophlebis nebbensis Brongniart, 1828 ) Nathorst, 1876, a typical Rhaeto-Liassic species from Europe and Asia is similar in its once forked secondary veins and slightly restricted pinnule bases, but the pinnules dimensions in C. nebbensis are larger (around 15 mm long) and the rachis is relatively thin ( Schweitzer et al. 1997).

Figures

Fig. 6. Cladophlebis fronds from the tuff layer in the basal part of “explosion breccia” (late Ladinian, Middle Triassic) of Monte Agnello, Dolomites, N- Italy. A. Cladophlebis ladinica sp. nov., partially fused basal pinnules (MGP 194/6B). B–E. Cladophlebis sp. B. Bipinnate frond fragment (MGP 194/88). C. Pinnae with slightly falcate pinnules (MGP 194/87). D. Detail of the slightly imbricate pinnules (MGP 63/71). E. Possible basal pinnae with broad pinnules (MGP 194/89A). Scale bars 10 mm.