Index Fungorum no. 346
Effectively published 23/11/2017 08:23:36 (ISSN 2049-2375)
Nomenclatural novelties : Mikael Jeppson and Ellen Larsson
Geastrum nigrum Jeppson & E. Larss., sp.nov.
Endoperidium globose to subglobose, 6–20 mm diameter, almost smooth to finely pubescent, papery, dark grey to black with an apical, undelimited tear or fimbriate/fibrillose pore reaching 2 mm diameter. Exoperidium rudimentary, with lobes bending outwards. Mature gleba dark brown. Spores globose 4.5–6.5 µm ornamentation excluded, coarsely verrucose. Capillitium undulating, 3.5–4 µm diameter with walls appr. 0.5 µm thick.
Holotype: GERMANY. Sachsen-Anhalt, Börde, Hadmersleben, Feldgehölz II, westlich unter dem Fuchsberg, Heinz Nowak, 8 May 1966, HAL 1816.
This species was invalidly published (no holotype indicated Art. 40.3, Note 1 IAPT Melbourne) as Disciseda nigra Dörfelt & H. Nowak, Feddes Repert. 113(1-2): 27 (2002). The holotype collection is in poor condition (overwintered and extremely weathered) and future collecting is needed to fully describe the exoperidial characters of this species. ITS sequence data (GenBank MG282096, holotype) show that the species belongs in Geastrum sect. Corollina and comes out as a sister species to G. corollinum.
Etymology: Nigrum refers to the dark coloured endoperidium of this species.