Entoloma chytrophilum Wölfel, Noordel. & Dähncke

Montañez, Diego, Noordeloos, Machiel E., Rodríguez, Olivia, Vargas, Ofelia & Guzmán-Dávalos, Laura, 2016, Notes on the genus Entoloma (Basidiomycota, Agaricales) in two volcanic areas of Jalisco, Mexico, Phytotaxa 277 (3), pp. 211-236 : 229-230

13. Entoloma chytrophilum Wölfel, Noordel. & Dähncke (in Wölfel & Noordeloos 2001: 190), FIGURE 13 .

Description:— Pileus 2–3 mm broad, convex, depressed, dry, dull, centre appressed-squamulose, elsewhere fibrillose, smooth, blackish blue to violet blue. Lamellae adnate to emarginate, subdistant, ventricose, whitish then pink, edge entire, concolourous. Stipe 4–6 × 0.5–1 mm, central, cylindrical, equal, fibrillose, with pruinose apex, longitudinally striate, concolourous with pileus. Context thin, colour not recorded. Odour not recorded. Taste not recorded.

Basidiospores 8.8–12.0 × (5.6–) 6.4–7.2 (–8.0) μm, Lm = 10.4, Wm = 6.8, Q = 1.3–1.8, heterodiametrical, 6–11 angled in side-view with blunt angles, somewhat nodulose, colourless. Basidia 22–31 × 9–11 μm, 4-spored, broadly clavate, colourless, clamped. Pleurocystidia absent. Cheilocystidia absent. Pileipellis a trichoderm, terminal elements 24–69 × 8–28 μm, broadly clavate to ellipsoid, with abundant greyish blue plasmatic pigment. Caulocystidia 26–60 × 6–11 μm, cylindrical, colourless, in small groups at the stipe apex. Clamp-connections present in all tissues.

Habit and habitat:—Gregarious, on rotten wood, in cloud forest.

Material studied:— MEXICO. Jalisco, Municipality of Zapotlán el Grande, El Floripondio, slopes of Nevado de Colima, 11 August 1990, O. Vargas 443 (IBUG!).

Comments:—Morphologically, the Mexican collections fits well with Entoloma chytrophilum that is a fairly distinct species with very small, dark blue changing to violet blue pileus, somewhat nodulose-angled basidiospores, and lignicolous habit. The species also figures in a recent phylogenetic study ( Morozova et al., 2014). Unfortunately, the Mexican material is rather scanty and old to get it barcoded, to compare it with the results of Morozova et al. (2014). Hopefully more material can be collected in the future. There are other similar species to E. chytrophilum , but all of them terricolous and they differ accordingly: E. coelestinum (Fr.) Hesler (1967) has smaller basidiospores; E. cyaneum Sacc. has larger basidiospores; E. lepidissimum (Svrček) Noordeloos (1982b) . has blue lamellae when young, a smooth stipe, and sometimes cheilocystidia; and E. subcoelestinum (Largent) Blanco-Dios (2015) , has non-nodulose basidiospores and lacks clamp-connections in the pileipellis ( Largent 1994, Noordeloos 2004, Morozova et al. 2015).

Figures

FIGURE 13. Entoloma chytrophilum. a. Basidiospores. b. Basidia. c. Pileipellis. d. Caulocystidia.All 1000×, except basidiospores 3000×. Drawings by Diego Montañez and Machiel Noordeloos.