Cyclotella marina (Tanimura, Nagumo & M. Kato) Ake-Castillo , Okolodk. & Ector, in Nova Hedwigia, Beih. 141: 267, figs 2-9. 2012.

Bilous, Olena P., Genkal, Sergey I., Zimmermann, Jonas, Kusber, Wolf-Henning & Jahn, Regine, 2021, Centric diatom diversity in the lower part of the Southern Bug river (Ukraine): the transitional zone at Mykolaiv city, PhytoKeys 178, pp. 31-69 : 31

Cyclotella marina (Tanimura, Nagumo & M. Kato) Ake-Castillo, Okolodk. & Ector, in Nova Hedwigia, Beih. 141: 267, figs 2-9. 2012.

Basionym.

Cyclotella atomus var. marina Tanimura, Nagumo & Kato in, Bull. Natn. Sci. Mus., Tokyo, Ser. C. 30: 6-7, figs 3-15. 2004.

Morphological description.

Frustule low-cylindrical, valve diameter is 3.2-3.9 μm, a clear boundary between edge and central zone is absent, striae wedge-shaped, 18-20 in 10 μm, central process is absent (Fig. 7B ).

Ecology.

According to literature data, C. marina has a high ecological relevance, with a preference in brackish waters, also inhabiting marine environments even with salinity ranges around 30‰; smaller numbers were recorded for freshwaters under 10‰ ( Tanimura et al. 2004; Chung et al. 2010; Aké-Castillo et al. 2012). There are known cases where C. marina exists in shallow waters with freshwater discharges. At the same time, the appearance of this taxon is connected to high nutrient concentrations. In addition, cases of blooming of this species are known in the south-eastern Gulf of Mexico ( Aké-Castillo et al. 2012).

Distribution.

C. marina is found in epilithic benthic samples at all investigated sites during this research for the Southern Bug River (Table 1 ). For Ukrainian territory it is also reported from Khmelnytskyy NPS, ( Genkal et al. 2012) and in phytoplankton in Odessa Bay of the Black Sea ( Genkal and Terenko 2014).

It is also a common species for Europe, North America, and Asia ( Aké-Castillo et al. 2012; Genkal et al. 2012; Guiry and Guiry 2021).

Figures

Figure 7. SEM (A-E, G, H) and LM images (F) of species found in the transitional zone at Mykolaiv city, valve views: A Cyclotella cryptica B Cyclotella marina C, D Cyclotella meduanae E, F Cyclotella meneghiniana G Cyclostephanos dubius H Cyclostephanos invisitatus, with arrows shown on A, D, H marginal and central fultoportulae, B marginal fultoportulae, F central fultoportulae. Scale bars: 2 μm (B, D); 4 μm (A); 5 μm (C, E); 10 μm (F-H).