Freshwater Ascomycetes - Species Monograph

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Genus	Species	Author
Ophioceras	tenuisporum	Shearer, J.L. Crane and Chen
Class	Order	Family
Sordariomycetes	Inc. sed.	Magnaporthaceae

Synonymy:

Description

Habit:

Saprobic on submerged woody debris.

Ascomata:

Ascomata superficial to partially immersed, scattered to clustered, globose to subglobose, 240-625 x 260-775 µm, black, with an extremely long beak.

Peridium:

Ascomal wall even throughout to slightly wider at base and near the beak, 54 µm wide, of textura angularis in surface view; outer layer 32 µm wide, of hyaline pseudoparenchyma; middle layer 22 µm thick, of laterally compressed pseudoparenchyma, cells partially covered and occluded with brown amorphous material; inner wall layer 8 µm wide, of laterally compressed hyaline pseudoparenchyma.

Beak:

Beak central, cylindrical, sometimes undulate, up to 20 mm long, 60-130 µm wide, tapering at apex, black, lighter at apex, of textura prismatica in surface view.

Hamathecium:

Hamathecium of long, tapering, septate, hyaline paraphyses.

Ascus:

Asci numerous, basal to peripheral, cylindrical to narrowly fusoid, tapering at both ends, without a stalk, 82-114 (x = 101, s = 7.4, n = 60) x 4-6 (x = 5.3, s = 3.5, n = 60), separating from hymenial layer at maturity, with eight ascospores in a single, parallel fascicle, with cylindrical ascus apparatus; ascus apparatus staining with aqueous cotton blue, 0.5-1.5 x 1 µm.

Ascospore:

Ascospores hyaline, filiform, curved to sigmoidal, narrow, more broadly rounded at one end than the other, 66-94 (x = 80, s = 7, n = 60) x 1-1.5 (-2) (x = 1.2, s = 0.3, n = 60) µm, 3 septate, multiguttulate; ascospores frequently released by deliquescence of basal half of ascus.

Sheath:

None observed.

Appendage:

None observed.

Culture:

Colonies on cornmeal agar hyaline at first becoming pale gray, immersed and superficial, compact, with even margin, growth rate 0.9 mm/da at 24C. (ATCC 56671)

Anamorph:

None observed.