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Page number:213 
Description type:Non-original description 
Description:Clavulicium venosum (Berk. & Rav.) Ginns, comb. nov. Basionym: Corticium venosum Berk. & Rav., Grevillea 1: 177, 1873.
Citation of type: 'Rav. No. 1321", fide Berkeley and Ravenel. Basidiome effuse, in pieces about 30 x 30 mm and 400 µm thick, horny, membranous; margin pallid (near 2.5Y8/4), fimbriate to reticulose, adnate, thin, up to 1 mm wide; hymenial surface smooth but with faint branched ridges which suggests it was rugose when fresh, pallid (near 2.5Y8/4) to blackish grey (near 2.5Y6/2); subiculum concolorous with hymenium, horny.
Hyphal system monomitic; subicular hyphae (Fig. 18) in some sections apparently in a gelatinized matrix, branched, 2-3 µm diam, with frequent clamp connections, the walls thin, hyaline, nonamyloid, acyanophilous; gloeocystidia (Fig. 16) scattered, originating in the subiculum next to the subhymenium, cylindrical, curved into the hymenium, imbedded or rarely projecting to 15 µm, 70-100 x 4-7 µm, the contents granular, refractive, and yellow-brown in Melzer's and 2% KOH, dark blue in cotton blue, sulfo-negative; hymenium and subhymenium about 70 µm thick; basidia (Fig. 17) cylindrical, about 35 x 5-7 µm, with two sterigmata, each about 8 µm long; basidiospores (Fig. 15) cylindrical-ellipsoid, 11.2-16.0 x 5.0-6.0 (-7.0) µm, the contents finely granular and subhyaline in KOH, the walls hyaline, thin, nonamyloid, cyanophilous, with a prominent, broad, blunt apiculum.
The only specimen known of this fungus is the type. Burt (1926) mentioned that the specimen at Kew had 'Auricularia" written on the label, but he was not able to confirm that the fungus had auricularioid basidia. Hjortstam (1989) after examining the part at Kew stated 'an auriculariaceous species', but gave no supporting facts. I found, with difficulty, only a few two-spored holobasidia and no auricularioid basidia.
In addition to the two sterigmate basidia this fungus has other features similar to those of Clavulicium macounii (Burt) Parm. Both have gloeocystidia which are similar in size, shape and contents, both have narrow hyphae, both have relatively large spores with granular or oily contents, and both have pale yellow, globular deposits, 15-20 µm diam in the basidiomes. The two are congeneric, hence the transfer to Clavulicium is proposed.
Specimen examined: South Carolina: Black Oak, Sept., on carious logs (very rotten), Ravenel 1321 (FH, Curtis Herb.).
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