Nitellopsis (Tectochara) aff. palaeohungarica (Trabelsi & Sames & Wagreich & Ḱazḿ & & Mart́ın-Clo, 2021)

Trabelsi, Khaled, Sames, Benjamin, Wagreich, Michael, K ́ azm ́, Miklos, , Andrea Mindszen & Mart ́ ın-Clo, d Carles, 2021, A new diverse charophyte flora and biozonation of the Eocene bauxite cover-sequence at G ant (V ertes Hills, Hungary), Journal of Systematic Palaeontology 19 (7), pp. 541-563 : 553

Nitellopsis (Tectochara) aff. palaeohungarica (Ŕasky,

1945) Grambast & Soulíe-M¨arsche, 1972

( Fig. 11J–N)

1945 Chara palaeohungarica sp. nov. Ŕasky: 38, pl. 1, figs 16–18.

1955 Tectochara palaeohungarica comb. nov. M ¨adler: 298.

1959 Tectochara palaeohungarica Horn af Rantzien: 90, pl. 8, figs 4–7.

1972 Nitellopsis (Tectochara) palaeohungarica nov. comb. Grambast & Soulíe-M¨arsche: 4.

Material. Twenty-eight gyrogonites in sample G-2.3 and 33 in sample G-2.5. Collection numbers of figured specimens: HNHM-PBO 1572–1576.

Description. Gyrogonites very large (900–1200 M m high and 800–1050 M m wide), oval, prolate spheroidal ( ISI 100–120) in shape, showing 8–11 (often nine) convolutions in lateral view ( Figs 11J–L, 13). Spiral cells concave to flat. Apex prominent with spiral cells protruding to form a central rosette. Spiral cells show both narrowing and thinning in the periapical area ( Fig. 11M). Base rounded to almost conical, occasionally lengthened in a short broad column. A large (155–230 M m) pentagonal basal pore occurs within a wide basal funnel ( Fig. 11N).

Distribution. The species ‘ Chara ’ palaeohungarica was first described from sub-surface beds attributed to the Paleocene in Dorog, Hungary, by Ŕasky (1945). Here this species is described from beds cropping out at Ǵant, which are probably time-equivalent to those of the type locality. The present study supports re-assignment of this species to the middle Eocene rather than to the Paleocene.

Remarks. The gyrogonites studied here are diagenetically deformed, which hinders a more definitive taxonomic attribution. A re-study of the type material (HNHM 55.1458 –55.1460) by one of the authors of this study (CMC) showed that, besides the holotype, which is a sub-spherical gyrogonite as illustrated by Ŕasky (1945, pl. I, fig. 16), there were more oval to elongated gyrogonites present in the collection similar to those described here, which Ŕasky (1945, 38) termed “cylindrical”.