Sistotrema macabouense G. Gruhn, Hallenb. & Courtec., 2017

Gruhn, Gérald, Hallenberg, Nils & Courtecuisse, Régis, 2017, Sistotrema macabouense (Cantharellales, Hydnaceae), a new corticioid fungus from Martinique, Phytotaxa 303 (1), pp. 65-70 : 66-67

Sistotrema macabouense G. Gruhn, Hallenb. & Courtec. sp. nov. ( Figs 1 , 2 )

Typus:—FRENCH WEST INDIES. Martinique: Le Vauclin, Forêt Domaniale du Littoral, Anse Grand Macabou (8 Aug 2012), LIP GG-

MAR12-213 —on dead wood of Coccoloba uvifera , white rot ; Two isotype specimens, herbarium GB, hb. Gruhn MAR12-213 . MycoBank no:— MB817953 Etymology:— macabouense indicates the collecting place, Anse Grand Macabou, a coastal forest in the east side of the Martinique

Island. Diagnosis:—differs from Sistotrema otagense by subceraceous basidiome, thin basal hyphae (2‒3 μm diam.), urniform basidia with long subcylindrical neck and narrow head, and more or less isodiametric spores.

Description:—Basidiome annual, effused (10 × 7 cm), adnate, strongly attached to the wood, subceraceous, thin, as greyish bloom when fresh, then yellowish and porulose under lens (×1000) in herbarium. Hymenium smooth. Margin not differentiated, without cords. Hyphal system monomitic, basal and subhymenial hyphae not differentiated, thin-walled, 2‒3 μm wide, with inconspicuous clamps at the septa. Cystidia not observed. Young basidia globose to pearshaped. Mature basidia scarce, typically urniform, with a short regular neck, basally clamped, 17–22(–25) × 6‒7 μm, 3.5 μm wide at the neck, content of basidia granular or including irregular bodies which are light refracting in phase contrast, with 4‒5(‒6) thin sterigmata. Spore print white, spores subglobose, more or less isodiametric, with a small apiculus, 5–6(‒6.5) × 4–5 μm, Qm= 1.2; thin-walled and smooth, acyanophilous, inamyloid, indextrinoid.

Material examined:— S. farinaceum : CANADA, British Columbia: Vancouver Island, Mesachie Lake, on fallen log of Populus (31 Aug 1982), typus, GB-659; S. cf. farinaceum : FRENCH GUIANA: Saül, Cripeu Limonade, “A” Diadema track, seasonally flooded forest, on unknown host (23 Oct 2013), hb. Gruhn GUY13-112; S. diademiferum : FRANCE: Mont Ventoux, Vaucluse, Integral Biological Reserve, plot 26, on unknown host (21 Oct 2010), hb. Gruhn 101021-108; plot 32, hb. Gruhn 101021-033 and 039 —Breil-sur-Roya, Alpes-Maritimes, Tête d’Alpe, Integral and Directed Biological Reserve, plot 3, on Abies alba (9 Oct 2014), hb. Gruhn 141009-142; S. otagense : NEW ZEALAND: Otago, Dunedin, Morrison’s Creek, on unknown host (Jun 1952), typus, PDD-11581.

Figures

FIGURE 1. Sistotrema macabouense (holotype). Basidia, hyphae and spores. Scale bars: spores 5 μm, basidia 10 μm.

FIGURE 2. Sistotrema macabouense (holotype). Basidiome, fresh material in situ. Scale bar 1 cm.