Raskyella peckii var. vadaszii ( Grambast & Grambast, 1954)

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 : 547-548

Raskyella peckii var. vadaszii ( Grambast & Grambast, 1954) comb. nov. Trabelsi & Mart́ın-Closas

( Fig. 6A–S)

Basionym. Raskyella vadaszi (Ŕasky) Grambast & Grambast (1954), 670.

1945 Aclistochara vadaszi sp. nov. Ŕasky: 45, pl. II, figs 22–24.

1954 Raskyella vadaszi comb. nov. Grambast & Grambast: 670.

1957 Raskyella vadaszi Grambast : 358, pl. 5, figs 1–6.

1959 Raskyella vadaszi Horn af Rantzien: pl. 20, figs 1–3.

1981 Raskyella vadaszi Anadon & Feist : pl. 1, fig. 5; pl. 2, fig. 5.

1981 Raskyella aff. vadaszi Anad́on & Feist: pl. 1, figs 3, 4; pl. 2, figs 1, 2, 6.

1985 Raskyella vadaszi Bignot et al. : 36, pl. 3, figs 8–11.

1986 Raskyella vadaszi Riveline : pl. 37, figs 1–6.

Material. Hundreds of gyrogonites in samples G-6a and G-6b. Collection numbers of figured specimens: HNHM-PBO 1517–1534.

Description. Large sized gyrogonites (800–1150 M m high and 800–1150 M m wide) of oblate to ovoidal shape ( ISI 80–120), showing laterally 7–10 (usually nine) convolutions ( Fig. 7). Spiral cells often convex and ornamented with stout tubercles of different shapes and sizes, in most cases oriented parallel to the intercellular sutures ( Fig. 6A–C), or more rarely tilted 20–30 Ǫ but keeping parallelism between adjacent nodules ( Fig. 6E–G), this being a diagnostic character of this morphotype. Three tubercle morphologies have been observed: (1) rounded tubercles, well individualized in the upper half of the gyrogonite, but fused to neighbouring tubercles in the lower half ( Fig. 6I, K); (2) elongated tubercles more or less connected to each other and producing slightly wavy (undulated) sutures ( Fig. 6H); and (3) irregularly alternating round and elongated tubercles ( Fig. 6D). Base of gyrogonite rounded ( Fig. 6C, J) to slightly tapered ( Fig. 6A, G) and showing a small, superficial and pentagonal basal pore, sometimes within a less-marked funnel ( Fig. 6Q). Apex of gyrogonite truncated or broadly rounded and covered by five independent opercular cells at the end of the spiral cells. Opercular cells roughly prismatic, with its outer surface concave, flat or slightly convex ( Fig. 6L, M). Germinated specimens show a rounded or rose-like opening ( Fig. 6N–P). The inside of the gyrogonite allows observation of a characteristic crenulation of the intercellular sutures near their internal side ( Fig. 6R, S), while, to the outside, sutures are flat. Besides, this crenulation occurs also between the opercule cells themselves and between spiral and opercule cells as already described by Feist in Anad́on & Feist (1981).

Distribution. R. vadaszii was first described by Ŕasky (1945) from middle Eocene borehole samples (60 m depth) at Ǵant, in beds roughly equivalent laterally to the outcrop succession studied here. Therefore, the samples studied may be considered topotypes. Subsequently, the age of this variety was suggested to be upper Bartonian by Bignot et al. (1985) based on the associated microfossils (foraminifers, ostracods and pollen) from the same beds of the bauxite cover-sequence at the Ǵant section (V́ertes Hills). R. peckii var. vadaszii has also been well documented in France, in the upper Bartonian of the Paris Basin ( Grambast 1957, 1958, 1962a; Riveline 1986) and from several basins in southern France ( Feist-Castel 1976). Anadon & Feist (1981) and Anad́on et al. (1992) documented this variety also in the upper Bartonian of the Eastern Ebro Basin (Catalonia, Spain).