The genus Mycena (Basidiomycota, Agaricales, Mycenaceae) and allied genera from Republic of São Tomé and Príncipe, West Africa Author Cooper, Alexandra C. Author Desjardin, Dennis E. Author Perry, Brian A. text Phytotaxa 2018 2018-12-13 383 1 1 47 http://dx.doi.org/10.11646/phytotaxa.383.1.1 journal article 10.11646/phytotaxa.383.1.1 1179-3163 13724481 2. Mycena aff. holoporphyra (Berkeley & M.A. Curtis 1869: 284) Singer (1962b: 64) . ( Fig. 6 ) Description:— Pileus 11–19 mm diam, broadly convex to campanulate with raised disc, becoming broadly convex to planar, margin pellucid-reticulate to tesselate, split in age; surface moist, glabrous, hygrophanous, dull, disc dark brown (7–8F4–8) with margin pale reddish brown (8E4). Lamellae horizontal, adnate with a decurrent tooth to arcuate, distant to subdistant with 1–2 series of lamellulae, subporoid to reticulate with shorter cross lamellae, greyish brown (8D–E3); edge concolorous. Stipe 20–30 × 1.5–2 mm , central, terete or flattened towards base, hollow; surface moist to dry, glabrous, dull, dark brown (8F4–5). Odour and taste not recorded. Bioluminescence undetected. Basidiospores 6.4–8.0 × 4.0–4.8 μm [x m = 7.36 ± 0.49 × 4.28 ± 0.39 μm, Q = 1.5–2, Q m = 1.73 ± 0.17, n = 20, s = 1], ellipsoid, smooth, hyaline, amyloid, thin-walled. Basidia 20–25 × 7.2–8.0 μm, clavate, hyaline, inamyloid, thin-walled, 4-spored, rarely 2-spored, sterigmata up to 8.0 μm long. Basidioles clavate. Lamellar edge sterile. Cheilocystidia 34–45 × 8.0–8.8 μm, fusiform to lageniform, hyaline, inamyloid, thin-walled. Pleurocystidia absent. Pileipellis a cutis; hyphae 1.6–4.8 μm diam, repent, cylindrical, smooth or sparsely diverticulate, hyaline, inamyloid, thin-walled, non-gelatinous; diverticula 1–2 × 0.5–1 μm, cylindrical. Hypodermium composed of inflated cells up to 19.2 μm diam, globose to ovoid, smooth, hyaline, dextrinoid, thin-walled. Lamellar trama regular; hyphae 2.5–8.8 μm diam, hyaline, dextrinoid, non-gelatinous, thin-walled. Stipitipellis a cutis; cortical hyphae 1.6–6.4 μm diam, parallel, cylindrical, hyaline, dextrinoid, thin-walled, non-gelatinous; medullary hyphae 8–20 μm diam, smooth, dextrinoid, thin-walled. Caulocystidia common at apex, scattered elsewhere, 30–67 × 5.6–11.2 μm, subcylindrical to fusoid, occasionally subcapitate or with one or more broad knobs, hyaline, inamyloid, thin-walled. Clamp connections present in all tissues. Habitat and known distribution:—Solitary in leaf mulch or soil in primary forest. ( São Tomé ). Material examined:—AFRICA. São Tomé , Macambrara radio antenna area, elevation 1300 m , N00˚16.557’, E06˚36.326’, 25 April 2008 , D.E. Desjardin, DED 8334 (SFSU). FIGURE 6 . Mycena aff. holoporphyra (DED 8334). a. Basidiospores. b. Basidia. c. Cheilocystidia. d. Pileipellis hyphae. e. Caulocystidia. Scale bar = 10 μm. Notes:— Mycena aff. holoporphyra is characterized by a convex to campanulate, reticulate-tesselate, dark brown pileus, arcuate, subporoid to reticulate, greyish brown lamellae, a dark brown stipe, basidiospores with mean 7.4 × 4.3 μm, fusiform to lageniform cheilocystidia, no pleurocystidia, a cutis-type pileipellis of smooth or sparsely diverticulate, non-gelatinous hyphae, subcylindrical to fusiform caulocystidia, and growth in leaf mulch in primary forest. In combination, these features indicate placement in sect. Calodontes . The New World M . holoporphyra ( type locality: Cuba ) differs from the São Tomé specimen in forming deep violaceous to vinaceous basidiomata and growing on wood (Pegler 1983). In all other macro- and micromorphological features they are indistinguishable. Until more material becomes available for the dark brown form described herein, we recognize it as Mycena aff. holoporphyra . Pairwise comparisons of aligned, overlapping ITS sequences of the São Tomé specimen (DED 8334) with the top ten BLAST results show 93.9–94.3% similarity to several sequences of M. pearsoniana (JN182201, FN394615, FN394616, FN394612), a member of sect. Calodontes . No sequences of New World M . holoporphyra are available for comparison. In the ITS phylogeny ( Fig. 2 ), Mycena aff. holoporphyra falls into the clade with other members of sect. Calodontes , sister to the bioluminescent Malaysian M . cahaya .