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 Add this item to the list   Gloiodon strigosum (Swartz ex Fries) Karsten
Page number:360 
Remarks (internal):Light apparently plays an important function in fruit body formation in culture. Cultures kept in darkness (except for short inspection periods every few days) for six weeks produced very rare and stunted fruit bodies. Within one week after removal from darkness to normal room lighting, the size of the fruit bodies nearly doubled, branches appeared, teeth were produced on the ventral surface of the upper stipe and lower branches, and significant numbers of fruit body primordia were produced elsewhere on the colony surface. Conversely, in cultures grown in normal room light throu hout their history, fruit body initials appeared within 3-4 weeks, and fruit body maturity was reached within six weeks (maturity being measured by ability to produce basidiospores).
Observations: Gloeocystidial structures, while not unique to cultures of this taxon, are conspicuous on the colony surface, and in the absence of fruiting (see below) help to distinguish the cultures.
Fruiting was initiated on some original isolates from fruit body teeth within several weeks (on malt agar slants). When vegetative mycelium was used as inoculum, no further fruiting occurred in a subsequent year of subculturing. Conversely, when portions of fruit bodies (teeth, stipe sections, etc.) were used as inoculum, fruiting on the subculture was initiated in about 60 days, and mature fruit bodies developed in an additional 60 days, all on or very near the inoculum (within 3 mm).
In a serendipitous series of events, it was found that a random light source (cultures rotated at random at least once per day before a lateral light source) permitted fruiting, but did not permit pileus formation. When semimature fruiting cultures were held in a constant position relative to the same light source, pileus formation followed stipe development normally, with subsequent production of hymenium-covered teeth.
During a malfunction of the illuminated incubator in which fruiting cultures were grown, the temperature reached 54 C, killing all fruiting cultures. Consequently, only vegetative cultures are now maintained in our laboratory.
Description type:Culture description 
Description:Gloiodon strigosum (Swartz ex Fries) Karsten
Key code: 1. 3. 15. 26. 33. 36. 38. 44. (48). 52.
Colony after six weeks covering agar surface, flat and very minutely granular from inoculum to approximately 4-8 mm, then abruptly farinaceous and very slightly raised;
mealy appearance gradually diminishing over 2-3 cm; advancing margin (up to 1.5 cm) appearing filamentous, diffuse, mostly submerged, very delicately silky; zones very subtle, at approximately 6-8 mm, 1.5 and 2.5 cm; color of farinaceous inner zone off-white, of farinaceous outer areas pallid sand color (appreciably darker when grown in light); fruit bodies rudimentary, produced only occasionally, simple, up to 4 mm high, approximately 1.5 mm thick, cylindrical, fleshy tan to cinnamon tan in color (somewhat darker when grown in light). Odor mildly aromatic, antiseptic. "Lead" hyphae of advancing margin up to 7 µm diam, somewhat thick-walled (wall up to 1 µm thick), hyaline, conspicuously clamped, producing narrow hyphae from or in juxtaposition to clamps; narrow submerged hyphae 1.5-2.5 µm diam, gnarled, tortuous, clamped, copiously branched; narrow surface hyphae appressed, producing differentiated structures, clamped.
Differentiated structures as follows: 1) Basidia 18-22 x 5.5-6.5 µm, clavate, clamped, hyaline, thin-walled (2)-4-sterigmate, the sterigmata very short, acute; contents homogeneous. 2) Gloeoplerous structures of two types: a) chrysocystidial elements up to 110 x 9 µm, clamped, elongatelanceolate to narrowly cylindrical, often with one or more short protuberances produced near origin, refringent under phase contrast; contents opalescent-guttulate, strongly cyanophilous, and b) subspherical to spherical-lobose, up to 25 µm diam, often with small abrupt lobes or narrow protuberances distally, resembling aborted sterigmata; contents as in cystidia. 3) Asexual sporophores short, up to 30 µm long, 1.5-2.0 µm diam, straight, often arising from a mass of gloecystidial elements, produced singly toward the advancing margin, in greater numbers in older portion of mat to form spore "heads."
Asexual spore masses up to 0.5 mm diam, white to pallid sand color, scattered randomly over younger portions of mat, becoming so densely crowded as to appear farinaceous in older areas. Spores 8.5-10.4 x 8.1-9.3 µm, blown out hyphal tips, without constriction at point of formation, produced singly, subspherical with thick nipple-like protuberance distally, smooth, thin-walled, becoming separated from the sporophore by a septum only late in development (spores released by rupture of basal septum, occasionally with a portion of the subtending sporophore cell attached as a pedicel);contents hyaline to refringent (usually) under phase contrast, strongly cyanophilous.
Fruit bodies produced randomly over colony surface; when mature clavarioid, branched irregularly, up to 1.5 cm high, with minute papillate teeth on lower surface of upper branches, brown where sterile, grey-brown where fertile.
Culture examined: Gloiodon strigosum. Lowell, Oregon 19 x .73, coll. J. L. Dodd, det. M. A. Donk, TENN no. 3422.
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