Gymnopus perforans (Hoffm.) Antonin & Noordeloos. 2008. Czech mycol. 60(1): 25.

Petersen, Ronald H. & Hughes, Karen W., 2016, Micromphale sect. Perforantia (Agaricales, Basidiomycetes); Expansion and phylogenetic placement, MycoKeys 18, pp. 1-122 : 43-50

5. Gymnopus perforans (Hoffm.) Antonin & Noordeloos. 2008. Czech mycol. 60(1): 25.

Basionym.

Agaricus perforans Hoffm.: S.F. Gray. 1821. Nat. Arr. Brit. Pl. 1: 622.

≡ Agaricus perforans Hoffm.: Fr. 1821. Syst. Mycol. 1: 138.

≡ Micromphale perforans (Hoffm.: Fr.) S.F. Gray. 1821. Nat. Arrang. Brit. Plants 1: 622.

≡ Marasmius perforans (Hoffm.: Fr.) Fr. 1838. Epicric. 385.

≡ Androsaceus perforans (Hoffm. : Fr.) Patouillard. 1887. Hymen. Eur.: 105.

≡ Marasmiellus perforans (Hoffm.: Fr.) Antonín & Noordeloos. 1997. Mycotaxon 63: 366.

Neotype

(fide Antonín & Noordeloos, 1997): Sweden, Medelpad, Borgsjö, Granbodsos, 31.VIII.1993, M.E. Noordeloos 93137 (L).

Diagnosis.

1) Fruiting habit on conifer needles, chiefly Picea ; 2) pileipellis and subpellis involved in thin mucoid matrix; 3) stipe barbed-vestured at least in lower half; 4) pileipellis lacking diverticulate hyphae and/or broom cells; 5) clamp connections ubiquitous; 6) cheilocystidia rare, broadly saccate to utriform; 7) lamellae few, reduced.

The following description is a rearrangement of that by Antonín & Noordeloos (2010) supplemented with current observations.

Basidiomata (Fig. 32A ) marasmioid. Pileus 5-13(-20) mm broad, plano-convex or subconcave, usually with small papilla, often with shallow central depression, sometimes faintly sulcate, hygrophanous, glabrous to matt, pallid brown to light brown ("wood brown" 7C4, “drab” 6D3, "buffy brown" 6C-D3-4) fading to pallid white in age. Lamellae rather distant, free, adnexed to narrowly adnate, with no anastomosis or interveining, subarcuate, total lamellae = 13-19, through lamellae = 1-3, segmentiform, 1-3 mm broad, pale pinkish brown, with concolorous or slightly paler, pastel off-white to pallid brownish orange ( “drab” 6C4) in age; edge entire. Stipe 15-40 × 0.5-1 mm, insititious, cylindrical, rarely compressed, stiff, filiform, finely sulcate lengthwise, vestured, at apex concolorous with pileus to "deep olive buff" 5B3, in lower parts dark brown ("Brussels brown" 6E5-6) to black, when mature often entirely black; vesture very sparse upward, setose only downward toward very base, which is usually densely hispid. Rhizomorphs (Fig. 32A ) abundant, -20 × 0.4-0.6 mm, tapering gradually to <0.2 mm broad, very curly, frequently branched, obviously binding adjacent needles and bits of debris, black, glabrous-shining. Odor fetid, like rotten cabbage; taste "mildly unpleasant," often tardily alliaceous.

Habitat and phenology.

In large troops on fallen needles of Picea , rarely also Pinus and/or Abies , in humus-rich, coniferous plantations; widespread over Europe and Scandinavia (perhaps also in Asia); July to November.

Pileipellis embedded in hyaline slime matrix, a thin ixocutis, composed of the following elements: 1) pileal hairs (Fig. 33A-D ) -120 × 3-4.5 µm, common, erect, thin-walled, conspicuously clamped, equal to slightly tapering distally and then with somewhat inflated apex; 2) repent hyphae 3-8.5 µm diam (Fig. 33E ), smooth, turgid on pileus surface, compactly interwoven, thin- to firm-walled (not thick-walled), conspicuously clamped; and 3) similar hyphae, occasionally delicately encrusted in stripes with minimal profile calluses. Pleurocystidia (Fig. 34 , 36A ) 35-42 × 7-8 µm, fusiform, rounded at apex (seldom acutely so), conspicuously clamped. Basidi oles (Fig. 35A ) clavate; basidia (Figs 35B-D ; 36B ) (-25)36-45 × 9-11 µm, clavate, often subcapitulate, (2-)4-sterigmate, conspicuously clamped. Basidiospores (Fig. 32B, C ) (5.5-)6.5-8.5(-9.5) × (3.5-)4-5 µm (Q = 1.50-2.57; Qm = 1.95; Lm = 8.10 µm), ellipsoid to narrowly pip-shaped, slightly tapered proximally, thin-walled, smooth, inamyloid. Lamellar edge heterogeneous. Cheilocystidia (Fig. 33C-M ) locally abundant, 30-41 × 10-29 µm, short- to long-stalked (stalk 3-10 × 3-4.5 µm, obscurely clamped), ventricose-rostrate, utriform to broadly, usually irregularly saccate to nearly globose, often with small pustulate outgrowths, significantly larger than pleurocystidia or basidia, thin-walled, hyaline; contents heterogeneous. Stipe medullary hyphae 2-9 µm diam, hyaline, strictly parallel, adherent in a slime matrix, conspicuously clamped, thick-walled (wall -1.0 µm thick, irregular on inner wall). Stipe cortical hyphae 4-7 µm diam, yellow-brown (PhC), strictly parallel, thick-walled (wall -2.0 µm thick), exteriorly smooth, vaguely dextrinoid (reddish brown in IKI, BF). Stipe vesture from near stipe apex composed of two elements: 1) broad, scattered, thick-walled caulocystidia as described below; and 2) long, flexuous, thin-walled “hairs” -140 × 1.3-3 µm diam, apparently thin- to firm-walled, arising from clamp connections (not as side branches), hyaline. Caulocystidia (Fig. 37 ) from lower stipe -90(-140) × 4-8.5(-13) µm, arising as side branches of stipe cortex surface cells, thick-walled (wall -2 µm thick, hyaline), erect, setoid, densely scattered, often in narrow clumps of 2-4 (appearing hispid at 30 ×), obscurely vacuolated, often internally secondarily septate, moderately dextrinoid (reddish brown in IKI, BF, especially reddish apically).

Commentary.

In a paper reporting on North American members of Gymnopus sect. Perforantia , inclusion of European G. perforans could be seen as counterintuitive, but not only is the European entity the name-bringer, but recognition that the North American collections are molecularly separable from the European necessitates a description of the European fungus, as above. As discussed also under G. sequoiae , the G. perforans complex seems composed of subclades with minimal base-pair percent separation. Such is the case with "European G. perforans ", which is separated from sequences from eastern North America by 1.65% bp divergence. Studies by Hughes et al. (2009) and others have shown that, in general, separation at species rank might be expected to be at least 3%. Using this standard, eastern North American collections do not warrant species rank. For this reason, we choose to propose the eastern North American collections at subspecies rank (see below under G. perforans subsp. transatlanticus ).

Specimens examined.

Finland, Etelä-Häme Prov., Lammi, Evo , Kotinen Virgin Forest , northwest part, 13.IX.1994, coll RHP, TFB 7477 ( TENN-F-53579) . Russia, Leningrad Oblast, Nizhne-Svirskiye Reserve, vic Kovkenitsky , N60°41.691', E33°17.965', 30.VIII.1999, coll N .

Psurtseva, TFB 10826 ( TENN-F-58295); same location, N60°36.766', E33°3.482', 29.VIII.1999, coll. RHP, TFB 10643 ( TENN-F-58251); Novgorod Reg., Valdai Dist. "Red Hill," Kasnaya Gorka, N58°06'37", E33°13'07", 21.VIII.2003, coll. RHP, TFB 11629 ( TENN-F-59592). SWEDEN, Trollhättan, vic Trollhättan, N58°17'01", E12°17'15", 22.IX.1991, coll SA Gordon, TFB 4721 ( TENN-F-50318); same location, N58°17'01", E12°17'15", 22.IX.1991, coll SA Gordon, TFB 4722 ( TENN-F-50319); Uppland, vic. Uppsala, Gottsundabergen, N59°48'27", E17°37'24", 7.IX.1994, coll. S-G. Ryman, TFB 7272 ( TENN-F-53624) .

Figures

Figure 32. Gymnopus perforans. Basidiomata and basidiospores. A Basidioma and rhizomorph B, C Basidiospores. Standard bars: A = 10 mm; B, C = 5 µm. A, B TFB 7272 (TENN-F- 53624). C TFB 7477 (TENN-F- 53579).

Figure 33. Gymnopus perforans. Pileipellis structures. A-D Pileal hairs E Repent hypha showing clamp connection. Standard bars = 10 µm. TFB 7477 (TENN-F- 53579).

Figure 34. Gymnopus perforans. Pleurocystidia. Standard bars: A = 10 mm; B = 5 µm. TFB 7272 (TENN-F- 53624).

Figure 35. Gymnopus perforans. Basidiole and basidia. A Basidiole B-D Basidia. Standard bars: A = 10 mm; B = 5 µm. TFB 7272 (TENN-F- 53624).

Figure 36. Gymnopus perforans. Hymenial structures. A Pleurocystidium B Basidium C-M Cheilocystidia. TFB 7272 (TENN-F- 53624).

Figure 37. Gymnopus perforans. Caulocystidia. A-F Full-size setoid caulocystidia G, H Small individual caulocystidia. Standard bars = 10 µm. TFB 7477 (TENN-F- 53579).