Cyanocohniella Kastovsky, Berrendero, Hladil et Johansen 2014, gen. nov.
Creators: name: Kaštovský, Jan
name: Gomez, Esther Berrendero
name: Hladil, Jindřich
name: Johansen, Jeffrey R.
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Bacteria
Cyanobacteria
Cyanophyceae
Nostocales
Nostocaceae
Cyanocohniella

description: Cyanocohniella Kaštovský, Berrendero, Hladil et Johansen, gen. nov. (Fig. 1).   
Thallus blue-green to dark green, filaments hypervariable in the course of the life cycle. Motile hormogonia germinating from akinetes, composed of 4–8 cells. Filaments developing from hormogonia with cylindrical cells, not constricted or slightly constricted at cross-walls, without sheath or with fine colorless or slightly yellowish, unlamellated sheath, slightly attenuated towards apices, with apical cells longer than wide, oval to conical, lacking calyptra. Filaments of next phase with marked constrictions at the cell walls, attenuated towards apices, with cells becoming oval to spherical, producing intercalary oval to spherical heterocytes and one- to two-celled apical hormocytes, with apical cells similar in form to common cells of the filament. Filament of mature phase with cells spherical, oval or irregularly shaped, with cells irregularly arranged in ensheathed filaments, sometimes evidencing cell division in two planes, producing partly biseriate filaments. Akinetes single or in series, with cell walls often yellowish. Necridia absent during entire life cycle.  
 Type species:— Cyanocohniella calida Kaštovský, Berrendero, Hladil et Johansen, spec. nov.   
 Habitat:— Thermal mineral water and atmophytic localities around thermal springs.   
 Etymology:— Genus is named in honor of Ferdinand Cohn, phycologist, who described Mastigocladus laminosus.   
 Description:— Population with a polymorphic life cycle. Hormogonia and young filaments with isodiametric to cylindrical cells, not constricted or slightly constricted at cross-walls, (1)1.5(2) µm wide, with intercalary cells (1)1.5–2.5 µm long, with apical cells longer than wide, oval to conical, 1.5–2.5 µm long. Sheath absent or thin, fine, colorless to slightly yellow (Figs. 1A–C). Intercalary cells gradually become constricted at the cross-walls and oval to spherical shape, (2)3.0–4.5(5) µm in diameter. Intercalary heterocytes rarely present, oval or spherical, 5–6(7) µm in diameter. Apical cells remain similar in form to intercalary cells, but may become less wide as filaments become attenuated towards apices (Figs. 1D–H). Mature filaments with cells spherical, oval or irregularly shaped, 2–7(8) µm in diameter, with cells irregularly arranged in ensheathed filaments, sometimes evidencing cell division in two planes, partly biseriate, with heterocytes rarely present, sheath colorless to slightly yellow, usually thin, unlamellated (Figs. 1K–N). Akinetes single or in series, spherical to oval, often with yellowish cell walls, 4–8(10) µm in diameter.
description: Published as part of Kaštovský, Jan, Gomez, Esther Berrendero, Hladil, Jindřich & Johansen, Jeffrey R., 2014, Cyanocohniella calida gen. et sp. nov. (Cyanobacteria: Aphanizomenonaceae) a new cyanobacterium from the thermal springs from Karlovy Vary, Czech Republic, pp. 279-292 in Phytotaxa 181 (5) on page 282, DOI: 10.11646/phytotaxa.181.5.3, http://zenodo.org/record/5150609