Freshwater Ascomycetes - Species Monograph

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Genus	Species	Author
Caryospora	obclavata	Raja & Shearer
Class	Order	Family
Dothideomycetes	Pleosporales	Zopfieaceae

Synonymy:

Description

Habit:

Ascomata on submerged wood, black, erupting from the substrate.

Ascomata:

Ascomata on wood 290–320 × 290–340 µm, black, carbonaceous, scattered, partially immersed, erupting from the substrate, broadly conical, ostiolate, papillate.

Peridium:

Peridium 40–45 µm thick; textura angularis in surface view; in longitudinal section composed of two layers; inner layer of pseudoparenchymatic cells 5–10 × 3–5 µm, outer layer of black carbonaceous material.

Beak:

Papilla 50 × 80 µm, short, broadly cylindrical; periphyses not seen.

Hamathecium:

Pseudoparaphyses trabeculate, branched and anastomosing.

Ascus:

Asci 115–160 × 32–50 µm (mean = 140 × 39 µm, n = 25), basal, bitunicate, fissitunicate, obclavate and broadly rounded at the apex, pedicellate, ectoascus splitting at the ascus apex, endoascus thick-walled, with a broad ocular chamber 13 × 12 µm, with eight ascospores, uniseriate at the apex and base and irregularly arranged in the middle.

Ascospore:

Ascospores 30–40 × 11–15 µm (mean = 34.5 × 13 µm, n = 30), broadly ellipsoidal to biconic, hyaline to pale green, becoming dark reddish brown at maturity, forming acicular crystals in glycerin or lactic acid, deeply constricted at the midseptum, slightly constricted below the apices; upper cell wider than basal cell, cells with one large guttule and several small ones; surface roughened; surrounded by a thin gelatinous sheath; sheath invisible in glycerin or lactic acid, 1-septate, but occasionally additional septa also seen near the tips of the ascospores.

Sheath:

Very thin gelatinous sheath; sheath not visible in glycerin or lactic acid.

Appendage:

None observed.

Culture:

Not cultured.

Anamorph:

None observed.

Other info

Type & Location:

TYPE. USA. FLORIDA: Apalachicola National Forest, Whitehead Lake, 30°09_54_N, 84°40_30_W, water 29 C, pH 7.5, on submerged, decorticated woody debris, 13 Jul 2004, HAR and CB, F79-1. (ILL40110).

Other Specimens:

Substratum:

Decorticated woody debris.

Habitat:

Lentic.

Distribution:

USA (FL)

Pertinent Literature:

Raja & Shearer 2008.

Comments:

See above reference.

Additional Pictures

Asci and ascospores.
Ascospores fixed in glycerin showing internal crystals.
Ascus showing the ruptured ectoascus.
Immature ascus showing elongation of endoascus .
Immature asci.

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