Lyrella circumsecta (Grunow ex A. Schmidt) D.G. Mann

Nevrova, Elena, Witkowski, Andrzej, Kulikovskiy, Maxim, Lange-Bertalot, Horst & Kociolek, J. Patrick, 2013, A revision of the diatom genus Lyrella Karayeva (Bacillariophyta: Lyrellaceae) from the Black Sea, with descriptions of five new species, Phytotaxa 83 (1), pp. 1-38 : 31

Lyrella circumsecta (Grunow ex A. Schmidt) D.G. Mann in Round et al. (1990: 672)

Basionym: Navicula polysticta var. circumsecta Grunow in Schmidt (1874a: pl. 3, fig. 27–28)

Navicula circumsecta (Grunow) Grunow in Cleve & Grunow (1880: 42)

Valves elliptic, length 65–95 µm, breadth 45–60 µm. Raphe straight, axial area very narrow, central area transversely elliptic, connected to lateral areas. Lateral area semi-elliptic, covered by dispersed coarse areolae. Transapical striae punctate, radiate, developed in marginal zone, 10–11 in 10 µm.

Distribution:—Found at the Sansego (Schmidt et al. 1874–1959). Black Sea, North-western region of the Black Sea ( Ryabushko 1991).

Literature:— Schmidt (1874a: pl. 3, figs 27–28); Cleve & Grunow (1880: 42); Round et al. (1990: 672); Ryabushko (1991: 14, no micrograph).