Roholtiella, gen. nov. (Nostocales, Cyanobacteria) - a tapering and branching cyanobacteria of the family Nostocaceae Author Bohunická, Markéta Faculty of Science, University of South Bohemia, Branišovská 31, České Budějovice 370 05, Czech Republic & Institute of Botany of the Czech Academy of Sciences, Dukelská 135, Třeboň, 379 82, Czech Republic Author Pietrasiak, Nicole Department of Biology, John Carroll University, University Heights, 1 John Carroll Blvd., Ohio 44118, USA Author Johansen, Jeffrey R. Faculty of Science, University of South Bohemia, Branišovská 31, České Budějovice 370 05, Czech Republic & Department of Biology, John Carroll University, University Heights, 1 John Carroll Blvd., Ohio 44118, USA Author Gómez, Esther Berrendero Faculty of Science, University of South Bohemia, Branišovská 31, České Budějovice 370 05, Czech Republic Author Hauer, Tomáš Faculty of Science, University of South Bohemia, Branišovská 31, České Budějovice 370 05, Czech Republic & Institute of Botany of the Czech Academy of Sciences, Dukelská 135, Třeboň, 379 82, Czech Republic Author Gaysina, Lira A. Department of Bioecology and Biological Education, M. Akmullah Bashkir State Pedagogical University, 450000 Ufa, Okt’yabrskoi revolucii 3 a, Russian Federation Author Lukešová, Alena Institute of Soil Biology of the Czech Academy of Sciences, Na Sádkách 7, České Budějovice 370 05, Czech Republic text Phytotaxa 2015 2015-02-11 197 2 84 103 http://dx.doi.org/10.11646/phytotaxa.197.2.2 journal article 10.11646/phytotaxa.197.2.2 1179-3163 13639648 Roholtiella mojaviensis Pietrasiak et Johansen , spec. nov. ( Figs. 3A–S ) Differing from all other species by having shorter, narrower, more consistently tapered trichomes ( Table 2 ) and bright blue-green pigmentation and desert soil habitat. Also differing from all other species in the sequence of the flanking regions of the Box-B and V3 helices of the 16S-23S ITS region ( Fig. 5 ). Type: — USA . Microscopic in sandy, gravelly soil from granitic outcrops, with plants and well-developed algal crusts, Joshua Tree National Park, Wonderland of Rocks, CA , N. Pietrasiak, June 2006 ( holotype : CBFS ! A-039-1). Refence strain: CCALA 1051. TABLE 2. Cell dimensions of Roholtiella strains investigated in detail. Reference strains for the type material are marked in bold. [x] row of arthrospores within the sheath, not yet released, (x) observed exceptionally.

Species	CCALA	Max cell	End cell	Cell	Heterocyte		Hormogonia		Arthrospores
Strain ID	width	width	length	length	width	length	width	length	width	length
R. edaphica	1055	6.4–10.3	4.1–4.8	3.2–6.4	2.0–	4.0–9.0	2.8–9.0	3.4–5.2	1.6–4.1	[7.0–	[3.3–8.5]
7.5(9.0)	10.2]
R. edaphica	1056	6.9–10.0	3.8–	3.6–6.4	2.0–	4.6–7.5	3.0–7.5	3.0–4.0	2.0–4.0	8.2–9.5	6.6–8.7
5.7(6.5)	7.2(9.0)
R. edaphica	1060	6.6–8.2	3.3–5.4	3.2–5.9	2.1–5.7	4.6–6.9	3.3–	3.3–4.4	1.7–4.1	6.1–8.2	[2.9]–8.2
6.4(8.5)
R. edaphica	1061	6.2–10.1	3.3–5.4	3.2–6.8	3.1–8.2	4.1–8.0	2.5–7.0	2.9–4.2	1.6–4.9	7.8–9.8	[3.3]5.6–
9.3
R. edaphica	1062	7.7–12.3	3.6–4.9	3.6–6.4	2.3–6.4	4.1–10.7	3.0–7.2	3.6–5.0	2.0–3.3	6.2–11.1	[4.1]–8.5
R. edaphica	1063	7.9–11.0	4.1–4.9	3.2–5.5	1.6–5.7	4.8–	2.8–7.5	(5.2–5.7)	(2.1–3.3)	6.9–9.0	4.6–9.3
8.0(10.1)
R. bashkiriorum	1057	6.6–9.8	3.3–6.6	4.1–7.2	3.0–8.2	4.6–8.2	2.5–7.4	2.5–4.0	1.6–3.0	6.2–10.2	5.0–9.0
R. bashkiriorum	1059	6.6–9.5	3.9–6.9	3.6–6.4	2.1–8.5	4.1–7.2	3.3–4.9	3.6–5.2	1.6–3.8	8.2–10.5	4.9–7.9
R. fluviatilis	1058	7.9–9.8	3.9–6.9	4.1–6.4	2.8–10.8	5.9–8.4	3.9–7.2	(5.2–6)	(2.8–4.0)	6.1–10.4	3.9–10.0
R. mojaviensi s	1051	5.7–9.6	3.3–4.6	3.2–5.5	1.6–6.6	4.3–7.4	3.2–6.8	2.8–3.6	2.0–3.6	5.6–7.9	4.1–7.5
R. mojaviensis	1052	5.7–8.4	2.8–5.2	3.2–6.4	2.1–7.3	N/A	N/A	2.9–4.2	1.6–4.1	4.5–4.9	4.9–9.0

Description: —Thallus evenly flat, spreading, appressed to the agar surface, growing into the substrate, blue-green to olive-green, rarely turning brown. Filaments short, sometimes single ( Figs. 3E, K ) or more rarely double ( Fig. 3D ) false branched. Sheath thin, attached, rarely widened and lamellated ( Figs. 3L, S ), firm, colorless to slightly pinkish ( Fig. 3S ). Trichomes constricted at crosswalls, slightly to distinctly tapered towards ends, commonly Calothrix -like with basal heterocyte at the slightly widened base, 5.7–9.6 μm wide. Cells shorter than wide, rarely longer than wide, cylindrical, barrel-shaped or compressed spherical, with smooth content, blue-green to olive-green, 1.6–7.3 μm long. End cells conical-rounded ( Figs. 3B–C, I ) or conical ( Figs. 3A, D, S ), 2.8–5.2 μm wide, 3.2–6.4 μm long. Heterocytes terminal, hemispherical or slightly conical, rarely intercalary in pairs, yellow or tan, 4.3–7.4 μm wide, 3.2–6.8 μm long. Arthrospores or rows of arthrospores released from the ends of the filament, with thick cell wall, almost spherical, olive-green, 5.6–7.9 μm wide, 4.1–9.0 μm long. Hormogonia constricted at crosswalls, typically 8–12 celled ( Fig. 3A ), without sheath or with sheath thin, attached, with cells 2.8–4.2 μm wide, 1.6–41 μm long. Habitat: —desert soil. Etymology: —From the Latin mojaviensis (= from Mojave Desert, USA ), referring to the geographical origin of the taxon. Other strain: —CCALA 1052 (CBFS! A–040-1)