Freshwater Ascomycetes - Species Monograph

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Genus	Species	Author
Pseudohalonectria	lignicola	Minoura et Muroi
Class	Order	Family
Sordariomycetes	Inc. sed.	Magnaporthaceae

Genbank ID: 42149

Synonymy:

None

Description

Habit:

Saprobic, ascomata immersed or partially immersed in submerged, dead woody debris.

Ascomata:

Ascomata 227-497 x 243-524 µm, solitary to aggregated, immersed to superficial, pale yellow at first, becoming darkened with age, rostrate, globose to flattened globose.

Peridium:

Peridium membranous, of textura angularis in face view, 13-15 cell layers thick, outer cells pseudoparenchymatic, darkened yellow and compressed laterally, inner cells pseudoparenchymatic, pale yellow.

Beak:

Beaks 170-621 x 65-221 µm, long, cylindrical, periphysate, composed of parallel hyphae, outer hyphae ending in enlarged, outwardly directed, subglobose cells.

Hamathecium:

Paraphyses 108-198 x 3.6-8.4, 1 to 5 septate, longer than asci, wide at base, tapering to a rounded point, thin walled, attached to ascogenous hyphae.

Ascus:

Asci 90-132 x 11-17.6 µm, unitunicate, cylindrical, straight or sigmoidal, with IKI-negative, thimble-shaped apical apparatus which stains bright blue in acidic aqueous cotton blue, containing eight ascospores in two overlapping fascicles of four, separating at the basal septum from ascogenous hypae and lying free in venter, lining the base and sides of ascomata.

Ascospore:

Ascospores 38-75 (x = 62.6) x 3.6-6.6 (x = 5.1), 5 to 11 septate, yellow in mass, becoming orange brown with age, hyaline to pale orange brown in transmitted light, cylindrical with bluntly rounded apices, sometimes allantoid, not constricted at the septa, discharged forcibly or accumulating in a mass at the beak opening.

Sheath:

None observed.

Appendage:

None observed.

Culture:

HUT, ATCC. Colonies on corn meal agar floccose, appressed, white at first, becoming pale to lemon yellow, pale yellow in reverse, colony margin even. Hyphae septate, smooth walled, 1-2.5 µm diam, hyaline.

Anamorph:

None reported.

Other info

Type & Location:

JAPAN: Shiga Pref., Lake Biwa, on balsa wood submerged from May 3 to July 30, 1976. HUT 40005.

Other Specimens:

Too numerous to list; see Database for references.

Substratum:

woody debris; balsa wood, twigs of Platanus occidentalis L. Acer saccharinum L., Prunus serotina Ehrh., unidentified woody debris, rarely herbaceous debris

Habitat:

lentic, lotic

Distribution:

Japan, USA (IL, IN, IO, MN, WI, MD)

Pertinent Literature:

Minoura, K. and Muroi, T. 1978. Transactions of the Mycological Society of Japan 19: 129-134. Shearer, CA. 1989. Canadian Journal of Botany 67: 1944-1955.

Comments:

Additional Pictures

Ascospore 2
Ascus 2
Peridium 1
Peridium 2

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