Freshwater Ascomycetes - Species Monograph

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Genus	Species	Author
Cyanoannulus	petersenii	Raja, J. Campb. & Shearer
Class	Order	Family
Sordariomycetes	Inc. sed.	Annulatascaceae

Genbank ID: 246475 MycoBank ID: 489363

Synonymy:

Description

Habit:

Saprobic, ascomata immersed to partly immersed on wood.

Ascomata:

Ascomata scattered, immersed to partially immersed, slightly horizontal, pale reddish brown, 405–800 x 214–297 µm; venter globose to subglobose.

Peridium:

Peridium of textura angularis in face view, in longitudinal section comprised of two regions: inner region of 2–3 layers of hyaline, thinwalled, elongated pseudoparenchymatic cells. 9–14 x 3–4 µm; outer region of 5–6 layers of dark walled cells 6–10 x 2–9 µm.

Beak:

Beaks central, long, cylindrical, tapering slightly at the apex, pale reddish brown, lighter color towards the apex, 340– 760 x 25–65 µm, periphysate.

Hamathecium:

Hamathecium of hyaline, septate paraphyses, constricted at the septa, 9–12 µm broad at the base, 6– 8 µm wide at the midpoint, tapering distally, 55–110 µm long.

Ascus:

Asci unitunicate, fuscoid, 8-spored, 73–142 x 8–12 µm (n=25), separating from the hymenial layer at maturity, with a bipartite cylindrical apical apparatus ca. 2–3 x 4–5 µm, nonamyloid, staining blue with aqueous cotton blue and aqueous nigrosin, apical body attached below apical apparatus staining blue with aqueous nigrosin.

Ascospore:

Ascospores thick-walled, hyaline, fusiform, flattened on one side, overlapping uniseriate, 3-septate, constricted at the septa, septa thick, with a narrow canal at the apices, containing a single large lipid globule in each central cell and smaller lipid globules in each end cell, 20–26.5 x 5–7 µm (mean= 23.5 x 6.3, SD = 1.8 x 0.66, n=50), surrounded by an ephemeral mucilaginous sheath extending 3–5 mm from the ascospore at the widest part.

Sheath:

Sheath present, surrounding entire ascospore, extending 3–5 µm from the ascospore at the widest part of the ascospore.

Appendage:

None observed.

Culture:

Anamorph:

None observed.

Other info

Type & Location:

USA, NORTH CAROLINA: Great Smoky Mountains National Park, Oconaluftee River, 35°34.201'N, 83°20.123'W, UTM Zone 290731 mE, 3936678 mN, water temperature 20 C, pH 5, on submerged, decorticated wood, 3 July, 2002, HAR & NH, R044-1. (ILL)

Other Specimens:

USA. TENNESSEE: Great Smoky Mountains National Park, Walker Camp Prong, 35°37.464'N, 83°26.300'W, water temperature 10 C, pH 5, on submerged decorticated wood, 20 July 2000, JC, R044-2; Middle Prong of the Little River, 35°37.469'N, 83°40.913'W, water temperature 22 C, pH 5, on submerged decorticated wood, 5 July, HAR & NH, R044-3; Rock Creek, 35°45.679'N, 83°12.643'W, water temperature 22 C, pH 5, on submerged decorticated wood, 6 July, HAR & NH, R044-4. COSTA RICA, Heredia, La Sevla Biological Station, Sura 60, small freshwater stream, 10°25'48"N, 84°1'32"W, UTM Zone 16, 825685 mE, 1154486 mN, water temperature 25 C, pH 5, on submerged decorticated wood, 18 May, 2000, JLA& RW, A497-1; Sura 100, small freshwater stream, on submerged wood, 6 February 2001, CMP, A497-2; Piper, small freshwater stream, on submerged, partially decorticated wood, 6 February, 2001, CMP, A497-3.

Substratum:

Submerged wood.

Habitat:

Lotic habitats.

Distribution:

North America (NC, TN), Costa Rica.

Pertinent Literature:

Raja, H.A., J. Campbell and C.A. Shearer 2004

Comments:

Additional Pictures

Beak.
Paraphysis with inflated basal cells.
Ascus apex stained with nigrosin.
Ascus and ascospores.
Ascospores fixed in glycerin and photographed with oil immersion lens.
Ascus apex fixed in glycerin and photographed with oil immersion lens.
Ascospore sheath

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