Freshwater Ascomycetes - Species Monograph

Click on the pictures below to view them at their full size.

Genus	Species	Author
Cercophora	aquatica	P. Chaudhary, J. Fournier & A. N. Mill.
Class	Order	Family
Sordariomycetes	Sordariales	Lasiosphaeriaceae

Synonymy:

Description

Habit:

Partially submerged wood of Alnus glutinosa and Quercus sp.

Ascomata:

Ascomata subglobose to obpyriform, 350–550 µm diam, 400–600 µm high, brownish black to black, solitary or gregarious, glabrous, strongly papillate, erumpent; subiculum composed of brownish, septate hyphae 2.5–3 µm broad.

Peridium:

Peridium areolate in surface view; in longitudinal section 2-layered, outer layer 15–21 µm thick, composed of 3–6 layers of dark brown, thick-walled, scleroplectenchymatous polygonal cells, 4–8.5 µm diam, cell walls 1.5–2.5 µm thick; inner layer 14–17 µm thick, composed of 4–6 layers of hyaline, thin-walled pseudoparenchymatous flattened cells up to 17 x 3.5 µm.

Beak:

Neck papillate with a rounded apex, ostiolate, periphysate, brownish black to black, sulcate or roughened.

Hamathecium:

Paraphyses filiform, 4–9 µm wide, hyaline, numerous, septate, unbranched, persistent.

Ascus:

Asci cylindrical, 180–250 x 13–16 µm, long-stipitate, stipe 70–100 x 2.5 µm, numerous, unitunicate, thin-walled, apex rounded; apical ring thickened, double, refractive, 3–3.5 µm broad, 1 µm high; subapical globule absent, with eight biseriate to triseriate ascospores.

Ascospore:

Ascospores cylindrical, 36–51 x 4–6 µm [43.9 ± 3.4 x 4.4 ± 0.5], sigmoid to geniculate, hyaline, aseptate, with several small oil droplets; bipolar appendages long, 38–45 µm, gelatinous, lash-like; becoming differentiated into an apical swollen head and a basal pedicel while inside the ascus; head ellipsoid, (13–) 15–18.5 (–21) x 7–12 µm, rounded at the apex, truncate at the base, hyaline to dark brown; pedicel 23–34 x 4–6 µm, hyaline; ascospore up to 5-septate after liberation from the ascus, each cell with a single, large refractive oil droplet, occasionally with inflated cells due to constrictions at the septa; occasionally producing phialides directly from the ascospore.

Sheath:

None observed.

Appendage:

Short, hyaline, bipolar gelatinous appendages present in early stages of ascospore development.

Culture:

Colonies on WA and CMA slow-growing, approximately 15 mm diam on WA and 30 mm diam on CMA in 28 d, fast-growing on OA, covering the plate in 21 d, mat silky on WA and CMA, hyaline, margin plumose, mat felty at the center on OA, yellowish-gre to grayish orange, surrounded by silver gray to bronze slightly appressed subfelty mycelia, margin even, appressed, hyaline, not distinct, developing ridges with deep furrows by the fourth week of incubation; reverse same as the mat in all media.

Anamorph:

Hyphae hyaline to pale brown, thin-walled, 1–3 µm wide. Conidiogenous cells phialides, produced from pale brown hyphae as a single terminal phialide, often branching into two or more phialides, sometimes percurrently proliferating, delimited by a basal septum, monophialidic, pale brown, cylindrical, 16–23 x 2.5–3 µm at widest part, slightly constricted at the collarette, 1–1.5 µm just below the collarette; colarette flaring, brown, darker than the phialide, 3–4.5 µm wide. Conidia pyriform, truncate at base, hyaline to pale brown, 2.5–3.5 x 2–3 µm [3.1 ± 0.2 X 2.5 ± 0.2]. Blastoconidia produced laterally on stalks 3–11 µm long or directly from hyphae, obovate to oblong, larger than the phialoconidia, 4–7 x 2–3.5 µm, hyaline. Anamorphs produced only on CMA.

Other info

Type & Location:

FRANCE, Arige, Rimont, ruisseau de Peyrau, 400 m elev., 29 Nov 2006, on recently exposed, submerged wood of Quercus sp. collected from a streambed, leg. J. Fournier (JF06314, ILLS 58443)

Other Specimens:

FRANCE, Arige, Rimont, ruisseau de Peyrau, 400 m elev., 26 July 2006, on recently exposed, submerged wood of Alnus glutinosa collected from a streambed, leg. J. Fournier (JF06165, ILLS 58442).

Substratum:

On recently exposed submerged woody debris of Alnus glutinosa and Quercus sp.

Habitat:

Lotic; on shallow streambed.

Distribution:

France.

Pertinent Literature:

Preeti Chaudhary, Jacques Fournier & Andrew N. Miller 2007.

Comments:

Appreciation is expressed to Preeti Chaudhary, Jacques Fournier & Andrew N. Miller for suppling a description and illustrations of C. aquatica.

Additional Pictures

Back