Inocybe media Eyssart. & Buyck 2022, sp. nov.

115. Inocybe media Eyssart. & Buyck, sp. nov. (Figs 9; 10)

DIAGNOSIS. — Differs from other species of the asterospora - pileosulcata clade in its smooth or irregularly angled spores, and its habitat corresponding to the African miombo woodlands.

HOLOTYPE. — Zambia. Along Luanshya-Ibenga road, gregarious in very young miombo woodland with Uapaca pilosa and U. kirkiana, 3.II.1996, Eyssartier 96083, BB 96.285 (holo-, P [PC0088770]).

INDEX FUNGORUM. — IF578795.

GENBANK. — EU600884 (LSU).

ETYMOLOGY. — Name formed by reference to the shape of the spores, intermediate between the smooth and the gibbous type, form the latin media, “intermediate, which is between two”.

Measuring 15-20 mm in diam., conico-campanulate with a large obtuse umbo that is pruinose from a white veil, clear ochraceous beige, pale beige brown with a reddish brown tinge or honey, even at the centre, towards the margin fibrillose, sometimes a little bit rimose.

Ascendant, 2-3 mm broad, emarginate, quite close, a pale beige ochraceous with white edges.

30-40 × 2-3 mm, sometimes flexuous, bulbous marginate (up to 4.5-6 mm), pale beige, white beige, pruinose lenghtwise.

White in the pileus and the base of the stipe, subconcolorous in the stipe.

Very faint.

A little bit herbaceous.

Of particular shape, smooth or irregularly angled with few inconspicuous nodules, intermediate between the smooth and the gibbose types, (8)9-12(13) × (5)5.5-6.5(7) µm.

Clavate, 4(2)-spored, 25-30 × 8-10 µm.

Clavate, (13)15-20(25) × 7-8(10) µm.

Very similar on sides and edge of gills, lageniform to broadly lageniform, (45)50-60(65) × 15-20(25) µm, with very thickened walls, (2)3-4 µm, up to 5 µm in the upper part; colourless or almost so in 10 % ammonia.

A cutis of subcylindrical or slightly inflated hyphae, 3-8 µm broad, broadened to 12-15 µm towards the underlying layer. Pigment brown yellowish, distinctly incrusting.

Present in all parts.

Although only a LSU sequence has been published for Inocybe media sp. nov., the species was part of multigene phylogenetic analyses (Matheny et al. 2009) where it is placed in a terminal clade with I. pileosulcata E. Horak, Matheny & Desjardin from Thailand, and with the European I. napipes J. E. Lange (Horak et al. 2015). Inocybe pileosulcata is associated with Dipterocarpus and is morphologically similar to the European Inocybe asterospora Quél., with which it was once confused (Horak 1979) and both species probably belongs to the same clade. All the abovementioned Inocybe have clearly gibbose spores with prominent knobs: Inocybe media sp. nov. is thus distinguished by its singular spores, of intermediate form between the smooth and gibbose type.