Lyrella majuscula (Hust.) Witkowski

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 : 20

Lyrella majuscula (Hust.) Witkowski in Moser et al. (1998: 353, pl. 76, fig. 3; pl. 79, fig. 1) ( Figs 86–94 )

Basionym: Navicula majuscula Hust. (1964: 522, fig. 1562)

Valves linear to linear-elliptic with broadly rounded to cuneate obtusely rounded apices, length 30–55 µm, breadth 14–16 µm. Raphe straight, external central endings moderately distant, axial area narrowly linear, central area narrow, transversely rectangular, frequently developed at one side and connected to lateral areas. Lateral areas narrow, slightly constricted in the middle, linear terminating below apices, encompassing 1/3 to 1/2 of the valve width. Transapical striae in the marginal part of the valve slightly radiate, very finely punctate, 12–14 in 10 µm.

Distribution:—Marine species known from the tropical part of the Pacific Ocean ( Witkowski et al. 2000); Black Sea, Crimean (Omega Bay, Cape Feolent, Balaklava Bay, Dvujakornaya Bay) and northern Caucasian coasts; recorded for the first time in the Black Sea diatom assemblages.

Literature:— Hustedt (1964: 522, fig. 1562); Simonsen (1987: 489, pl. 750, figs 3–7); Moser et al. (1998: 353, pl. 76, fig. 3; pl. 79, fig. 1); Witkowski et al. (2000: 234, pl. 96, fig. 5)

Figures

FIGURES 86–95: Lyrella majuscula. Figs 86–92: Valve view, LM, scale bar = 10 µm. Figs 93, 94: Internal view, SEM, scale bar = 6 µm and 9 µm, respectively. Specimens from the Black Sea (Omega Bay, Cape Feolent, Balaklava Bay, Dvujakornaya Bay). Fig. 95: Lyrella spectabilis, valve view, LM, scale bar = 10 µm. Specimen from the Black Sea (Dvujakornaya Bay).