Staurastrum cyclacanthum var. pseudobrevissimum W. W. A. Kowalski et K. Komarzewska 2024

¬ Staurastrum cyclacanthum var. pseudobrevissimum W.W.A. Kowalski et K. Komarzewsk. var. nova, Fig. 8L–O – Appendix 1 Basionim: lack Synonym: lack Description: Hexagonal cells, almost as long as they are wide, deeply narrowed. Length of cells without spines 34.7–35.0 µm, length with spines 38.9–39.1 µm, width without spines 36.8 µm, width with spines 40.05–41.05 µm, isthmus 7.8–8.4 µm wide. The sinus in the outer part is wide open and linear, at the end it is short and narrow and sharply cut. The semi-cells are trapezoidal, cup-shaped, with a slightly convex top and equipped with 6 papillae. From above, the half-cells are triangular in shape, with three slightly wavy sides. The central protrusion takes up about 1/3 of the side length. On both sides there are smaller bulges of the wall separated by gentle and shallow bays. Along each of the walls of the triangular surface of the half-cell there are two papillary protuberances, arranged parallel to its side, each of which is equipped with two strong spines, 3.15–3.68 µm long. The corner parts of the triangular half-cells are broadly rounded, equipped with two spines, 3.15–3.68 µm long, below which there is an additional pair of short papilla-like processes. The remaining surface of the cell walls is without ornamentation. * – according to Palmar-Mordvienceva (1982); ** – according to Palmar-Mordviencevwa (2005); *** – according to. Croasdale, Flint (1988); **** – according to W. et G.S. West (1902) Comments: The found cells in terms of form, size and ornamentation correspond to the characteristics of Staurastrum cyclacanthum W. et G.S. West, however, they differ from both the form of the nominal species and the previously described variety of S. c. var. brevissimum Pal.-Mordv. The table below provides the basic parameters and characteristic features of the species S. c. var. b revissimum Pal.-Mordv. and the variety found. ** – according to Palmar-Mordvienceva (2005) Distribution in Poland: Unknown. The occurrence of the variety in the algae flora in Poland has not yet been recorded in the Catalog of Polish prokaryotic and eukaryotic algae, neither Catalog of prokaryotic and eukaryotic algae in Poland (Siemińska, Wołowski, 2003) as well as nor in the icon library of the Institute of Botany. W. Szafer in Kraków. This form of cells has not been found in the basic algological literature (W. et G.S. West, 1912, 1923; Hirano, 1959, 1960; Coesel, 1997; Coesel, Meesters, 2007; Lenzenweger, 1997; Palmar-Mordvienceva, 1982, 2005; Kanetsuna, Yamagishi, 2018. General distribution and ecology: Staurastrum cyclacanthum var. brevissimum and S. c. var. dissimile were described by Palmar-Mordviencev (1982) from lake waters in Ukraine. Nominal taxon S. c. var. cyclacantum W. et G.S. West was described from lakes in the lake area of Western Europe. The occurrence of the S. c. var. cyclacantum W. et G.S. West in New Zealand was confirmed by Casdale, Flint (1988). The authors also report its occurrence in Sri Lanka and South America. The source literature on the ecology of the nominal taxon and its varieties does not contain detailed information on the habitat parameters of the species. Found in site: Measurements of basic ecological parameters and hydrochemical features of water in the post-peat reservoir No. 1 at the research date are given in Tab. 3. Table 2 compares the features characteristic of Staurastrum cyclacanthum W. et G.S. West var. brevissimum Pal.-Mordv. and varieties S. c. var. pseudobrevissimum W.W.A. Kowalski et K. Komarzewska var. nova.