Hymenomonas roseola F. Stein, 1878

Ignatenko, Marina & Yatsenko-Stepanova, Tatyana, 2023, Coccolithophores in the algal flora from South Urals (Russia) with the description of a new Hymenomonas species, Phytotaxa 609 (1), pp. 55-64 : 57

Hymenomonas roseola F. Stein ( Figs. 2–4 )

Coccolith is bowl-shape (murolith), with more or less straight sides. The funnel-shaped part of the coccolith expands towards the top and has a jagged edge. The number of calcite “teeth” (crystal units) of coccoliths belonging to single cell varies from 11 to 15. The height of coccoliths in the discovered specimens varies within 0.50–1.12 µm; the height of the base and the height of the funnel are approximately the same.

This species was observed in Ural River and Ushkotinsky Reservoir (see Table 2 ).

Figures

FIGURES 2–7. Coccolithophores from the reservoirs of the steppe zone of the South Urals (SEM). Figs. 2–4: Hymenomonas roseola. Figs. 5–7: Jomonlithus littoralis. The arrows mark the preserved areas of the organic basal plate. Scale bars: 2, 6–5 µm, 3, 4, 7–2 µm, 5–1 µm.