Freshwater Ascomycetes - Species Monograph

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Genus	Species	Author
Boerlagiomyces	websteri	Shearer & J.L. Crane
Class	Order	Family
Dothideomycetes	Pleosporales	Tubeufiaceae?

Synonymy:

Description

Habit:

Ascomata superficial on submerged wood.

Ascomata:

Ascomata scattered, superficial, obpyriform to ampuliform, rostrate, membranous, brown, setose, 220-423 x 200-218 µm.

Peridium:

Peridium two-layered, of textura angularis in surface view, 55-85 µm thick; inner layer 9-10 µm thick consisting of three to four layers of hyaline, compressed, fusiform cells; outer layer with three to four cell layers of textura angularis, 46-75 µm thick. Setae lanceolate, stiff, dark brown, one to to two-septate, scattered over ascoma but concentrated around beak, (50-) 55-175 (-233) µm long, 3.3-5.5 µm wide at base, tapering gradually to 2.2-3.3 µm wide at apex, originating from surface cells of ascomal wall.

Beak:

Beaks central, membranous, rounded at apex, wall undifferentiated anatomically from ascomal venter, setose, ostiolate, periphysate, (50-) 70-140 x 70-120 µm.

Hamathecium:

Pseudoparaphyses cellular, simple or branched, constricted at septa, 2.2-4.4µm wide; chains of clavate, thin-walled, hyaline cells lining ascomal venter and surrounding the central fascicle of asci.

Ascus:

Asci few, fissitunicate, two-spored, fasciculate, cylindric-clavate, rounded at apex, tapering at base to a short stalk, basal, 164-214 (-278) x 20-43 µm, ascus apex slightly thickened and rigid and shed as a cap during ectoascus dehiscence. In dried specimens, endoascus is retracted from ectoascus except at the ascus apex resulting in a dome shaped structure at the apex of the endoascus.

Ascospore:

Ascospores forcibly discharged from asci and ascomata, oblong, broadly rounded at ends, at first hyaline becoming uniformly golden brown to brown, dictyosporous with nine transverse septa formed early in development and one to three vertical septa within each cell layer, connected by cytoplasmic strands throughout development and after release from ascus, 66-92 (-107) x 26-35 µm.

Sheath:

Surrounded by a gelatinous sheath, very broad at early stages, becoming thinner as ascospores mature, and, finally, difficult to detect at ascospore maturity.

Appendage:

Culture:

Colonies on yeast extract soluble starch agar with balsa wood grown at 24C mostly immersed, dark brown, aerial hyphae greyish white. Subiculum lacking on natural substrate or when grown in culture on alfalfa stems. ex type ATCC 96580

Anamorph:

Unknown.

Other info

Type & Location:

USA. Illinois: Johnson Co., Cache River at foot bridge to Heron Pond, a dried culture isolated from muddy, submerged, decorticated wood, 3 Oct. 1992, C.A. Shearer and J.L. Crane, A-59-1 ILLS 51611.

Other Specimens:

ILLS, UTM

Substratum:

Decorticated wood.

Habitat:

Lotic.

Distribution:

USA (AK, FL, IL)

Pertinent Literature:

Shearer, C.A. & J.L. Crane. 1995. Boerlagiomyces websteri, a new ascomycete from fresh water. Mycologia 87: 876-879.

Comments:

Additional Pictures

Ascus1
Ascus3
Ascus4
Ascomata2
Sheath1

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