Timaviella dunensis sp. nov. from sand dunes of the Baltic Sea, Germany, and emendation of Timaviella edaphica (Elenkin) O. M. Vynogr. & Mikhailyuk (Synechococcales, Cyanobacteria) based on an integrative approach Mikhailyuk, Tatiana Vinogradova, Oksana Holzinger, Andreas Glaser, Karin Akimov, Yuri Karsten, Ulf Phytotaxa 2022 2022-02-02 532 3 192 208 Mikhailyuk & O.M. Vynogr. Mikhailyuk & O. M. Vynogr. 2022 [136,713,1852,1879] Cyanophyceae Oculatellaceae Timaviella GBIF Bacteria Synechococcales 6 198 Cyanobacteria species dunensis sp. nov.   Diagnosis:Morphologically and ecologically similar to  T. edaphicadiffering in the colorless sheath, wider filaments and trichomes, conical end cells, longer Box-B and D1-D1’ helices; structure of V3 helix in the position 9-50 and of basal stem and terminal loop in V2. Differs from  T. circinatain Box-B and V3 helices length, the structure in the D1- D1’, Box-B and V3 helices, as well as the color of thallus, rare false branching, wider trichomes, parallel thylakoids and presence of necridia.   Description:Thallus radially spreading, expanded, leathery, brownish, dark olive, blue-green to light greenish. Filaments long, variously curved, (3.0) 3.8-4.9 (6.0) μm wide. False branching rare, mostly double. Sheath colourless, firm, thick. Trichomes slightly constricted at cross-walls, occasionally becoming almost biseriate due to oblique division and compression of cells, 2.2–3.3 μm wide. Cells cylindrical, isodiametric to longer than wide, with parietal thylakoids, 2.2–3.5 μm long. End cells rounded to conical. Necridia in both young and senescing trichomes, hormogonia rare. D1- D1’ helix 85 nucleotides long, with a 3’ unilateral bulge at position –/ 73-80, five internal loops at position 10/68, 14- 15/63-64, 20/58, 23/54-55 and 31/46. Terminal loop having sequence 5’-UCUC-3’. Box B helix 48 nucleotides long, with several assymetrical internal loops at position 6/41–42, 9–10/39 and –/30–32. Terminal loop 5 nucleotides long, 5’-AUAAU-3’. V2 helix 10 nucleotides long, terminal loop 4 nucleotides, 5’-AUUA-3’. V3 helix 60 nucleotides long, with several internal loops at positions 4/53–55, 9–10/47–50 and 23/34. Terminal loop having sequence 5’-GAAA-3’.   Etymology: Named for its occurrence in biocrusts on dunes;  dunensis(L) = of dunes.     Holotypehere designated:KW-A-32531, Algotheca, Herbarium of the M.G. Kholodny Instituteof Botany of the National Academy of Sciencesof Ukraine(KW), Kyiv, Ukraine.  Reference strain:Us-6-3 was deposited at the German Collection for Microorganisms and Cell Cultures ( DSM112875), Braunschweig, Germany, as well as at culture collection of the M.G. Kholodny Institute of Botany of the National Academy of Sciences of Ukraine(IBASU-A-754).  Type locality:  Thecoast of the Baltic Sea, Usedom Island, vicinity of Zempin, Germany, 54°04′17″ N 13°58′04″ E, collected on  8 October 2013by Tatiana Mikhailyuk. Sand dunes, biocrusts with dominance of cyanobacteria and streptophyte algae. 3462289302 M. G. Kholodny Institute Ukraine National Academy of Sciences Kholodny Institute of Botany 12 204 1 Kyiv holotype 3462289303 2013-10-08 Germany Zempin 54.07139 The 17 13.967777 Usedom Island 13 205 1