Micromphale sect. Perforantia (Agaricales, Basidiomycetes); Expansion and phylogenetic placement Petersen, Ronald H. Hughes, Karen W. MycoKeys 2016 2016-12-15 18 1 122 217172DB-856A-5B36-87DF-4E8B15784A37 R. H. Petersen R. H. Petersen 2016 Agaricomycetes Omphalotaceae Gymnopus CoL Fungi Gymnopus sublaccatus Agaricales 92 93 Basidiomycota species sublaccatus sp. nov.   Holotype.  Canada, British Columbia, Victoria, Saanich Peninsula, Observatory Hill, N48.5262°, W123.422°, 4.XI.2011, coll & det O. Ceska (as  Marasmius androsaceus), UBC-F-25212.   Etymology. sub- = Latin: less than; laccatus = Latin: appearing polished or varnished, referring to varnished appearance of dried pileus.  Diagnosis. 1) Fruiting on needles of  Thuja(and  Pseudotsuga); 2) cheilocystidia rare, small, clavate, smooth, without setulae; 3) stipe near ochraceous buff above, downward rusty brown; 4) pileal hairs usually smooth, rarely roughened; 5) dried pileus sublaccate; 6) pileipellis of smooth, unencrusted, repent hyphae in slime matrix; 7) rhizomorphs inconspicuous, with minute black basal pad.  The following description is based solely on dried material.  Basidiomata(Fig. 78A) diminutive. Pileus2-8 mm broad, convex to plano-convex, minutely laccate, vaguely tuberculate, not striate or sulcate; disc about"sayal brown" 6C5 to "ochraceous buff" 5A5; limb and margin about "light ochraceous buff" 5A4 to "tilleul buff" 7B2. Lamellae(Fig. 78A) pseudocollariate (dried), adnate, distant, thickish, total lamellae = 20-23, through lamellae = 9-11, now (dried) "tilleul buff" 7B2 to "olive buff" 3B3; lamellulae in a single rank. Stipe18-25 x0.6-0.8 mm, terete, equal, hollow to lightly stuffed, subinsititious, minutely shaggy tosilky above, downward becoming minutely barbed (35 x), above about "ochraceous buff" 5A5, downward through "army brown" 8D5, increasingly dark to rusty brown ( "Prout'sbrown" 5F6 to "Vandyke brown" 7E6), sometimes slightly expanded at base; stipemedulla white. Rhizomorphs(Fig. 78C) (if produced) inconspicuous, often represented only by minute, black basal pads. Tasteand odornot recorded.   Figure 78.  Gymnopus sublaccatus. ABasidiomata showing adventitious rhizomorphs and stipe insertion to pileus BBasidiospores CSubstrate scales with back spots and rhizomorphs. Standard bars: A= 20 mm; B= 5 µm; C= not to scale. UBC 25212.  Habitat and phenology. Fruiting on needles of  Thuja plicata, less often on  Pseudotsuga menziesii; British Columbia; Autumn to early Winter.  Pileipellisinvolved in a slime matrix which includes detersile encrusting material, of the following elements: 1) pileal hairs (Fig. 79) -150 x3-6 µm, erect, firm-walled, smooth or rarely weakly roughened, slightly subcapitulate; 2) repent hyphae 4.5-7.5 µmdiam, firm-walled, conspicuously clamped but often secondarily septate, without discernable slime sheath. Pileus and lamellar tramae loosely interwoven; hyphae 3-5.5 µmdiam, smooth, firm-walled, without slime sheath, conspicuously clamped. Pleurocystidia(Fig. 80A-D) 25-35(-41) x7-8 µm, fusiform to clavo-fusiform, without partitioned contents but with vague vacuolated area in midsection (PhC), conspicuously clamped. Basidioles (Fig. 80E) clavate; basidia(Fig. 80F-H) 24-27 x8-9 µm, clavate, 4-sterigmate, clamped; contents multigranular at maturity; effete pleurocystidia and basidia emptying but not col lapsing( "husking"Fig. 81B); subbasidial hyphae (Fig. 81A) rupturing at clamp connections, appearing beaded. Basidiospores(Fig. 78B) (6.5-)7-7.5(-8) x(3.5-)4-5 µm(Q = 1.40-1.88; Qm = 1.67; Lm = 7.20 µm), rotund-ellipsoid, smooth, thin-walled, inamyloid. Cheilocystidia(Fig. 82) very locally common, usually rare to absent, 14-22 x8-12 µm, clavate to utriform, thin-walled, obscurely clamped; contents homogeneous. Stipe medullary hyphae(Fig. 81C) 4-12 µmdiam, strictly parallel, apparently free (no discernable gelatinized matrix, hyaline, thick-walled (wall -0.7 µmthick, hyaline, non-gelatinized), obscurely clamped, often with small side-branches ranging from lobate to rudimentarily branched. Stipe cortical hyphae4-8 µmdiam, strictly parallel, apparently free, thick-walled (wall -1.2 µmthick, especially at stipe surface), pigmented (yellow-brown, KOH + PhC), appearing moderately dextrinoid (IKI + PhC), or not so (IKI + BF), often producing broad-based side branches. Caulocystidia(Figs 83, 84) -45 µmat stipe apex, -140 µm atstipe base, x5.5-10 µm, ranging from lobate to elongate-digitate, without basal clamp, often internally secondarily septate, sometimes branched in one rank, thick-walled [wall -4 µmthick, often occluding cell lumen, pigmented (yellow-brown PhC)].   Figure 79.  Gymnopus sublaccatus. Pileipellis elements. A-EPileal hairs FSecondary septa of pileipellis hypha. Standard bars = 10 µm. UBC 25212.   Figure 80.  Gymnopus sublaccatus. Hymenial elements. A-DPleurocystidia EBasidiole F-HBasidia. Standard bars = 10 µm. UBC 15356.   Figure 81.  Gymnopus sublaccatus. ASubbasidial hyphae appearing beaded BEffete hymenial structures without collapse ( "husking") CStipe medullary hyphae. Standard bars = 10 µm. UBC 25212.   Figure 82.  Gymnopus sublaccatus. Cheilocystidia. Standard bars = 10 µm. UBS 15356.   Figure 83.  Gymnopus sublaccatus. Caulocystidia from stipe apex. Standard bars = 10 µm. UBC 25212.   Figure 84.  Gymnopus sublaccatus. Caulocystidia from stipe base. Standard bars = 10 µm. UBC 25212.  Commentary. With slime matrix covering the pileus surface and involving hymenial structures, with characteristic clavate cheilocystidia and with vestured stipe, UBC 25212 seems certain to belong in sect.  Perforantia. There it joins  G. perforans,  G. foliiphilusand  G. sequoiaewith the same general characters. From  Ma. androsaceus,  G. sublaccatusdiffers in pigmented (not black), vestured stipe. If its substrate preference is limited to  Pseudotsuga, this constitutes another difference. Finally, pileipellis of  G. androsaceusis characterized by diverticulate hyphal segments and broom cell-like hyphal termini, unlike that of  G. sublaccatuswhich lacks these structures. Basidiomata of  G. sequoiaeresemble those of  M. sublaccatusin stature and size, but seems limited to fruiting on needles of  Sequoia sempervirensin northern California. Cheilocystidia are shaped like an incandescent bulb, sometimes slightly askew, but otherwise quite typical of cheilocystidia in this taxonomic complex (compare, for example, thoseof  G. bulliformisand of  G. sequoiae). Difficult to distinguish from immature basidia, such cheilocystidia are less obscure after several sightings.  Specimens examined.    Canada,  British Columbia, Queen Charlotte Islands, Burnaby Island, Section Cove, N52°24'35", W131°19'55", 8.IX.2006, coll PK Kroeger(as  Marasmius androsaceus), PK 489 (UBC F18168);  Queen Charlotte Islands, N52°21'23", W131°24'24", 11.IX.2008, coll P. Kroeger(as  Marasmius androsaceus), PK 5904 (UBC F16670);  Queen Charlotte Islands, Ellen Island, N52°09', W131°06', 10.IX.2004, coll & P. Kroeger, B. & C. Kendrick, J. Brown, (as  Marasmius androsaceus), PK 2932 (UBC F15356);  Queen Charlotte Islands, Ross Island, N52°10', W131°07', 2.IX.2006, coll P. Kroeger(as  Marasmius androsaceus), PK 4347 (UBC F17675);  Victoria, Saanich Peninsula, Observatory Hill, N48.5262°, W123.422°, 4.XI.2011, coll & det O. Ceska(as  Marasmius androsaceus), UBC-F-25212 ( holotype). F18168 2006-09-08 PK Kroeger Canada Queen Charlotte Islands 52.409725 Section Cove 17 -131.33194 Burnaby Island 1 British Columbia F16670 2008-09-11 P. Kroeger Canada 52.356388 Queen Charlotte Islands 17 -131.40666 1 British Columbia F15356 2004-09-10 P. Kroeger, B. & C. Kendrick, Brown Canada 52.15 Ellen Island 1085 -131.1 Queen Charlotte Islands 1 British Columbia F17675 2006-09-02 P. Kroeger Canada 52.166668 Ross Island 1085 -131.11667 Queen Charlotte Islands 1 British Columbia 2011-11-04 O. Ceska Canada Victoria 48.5262 Observatory Hill 36 -123.422 Saanich Peninsula 1 British Columbia holotype