Gliophorus irrigatus A. M. Ainsw. & P. M. Kirk 2013

Gliophorus irrigatus (Pers.) A. M. Ainsw. & P. M. Kirk 2013 (Index Fungorum 23: 1, 2013) Agaricus irrigatus Pers., Syn. meth. fung. (Göttingen) 2: 361 (1801). Basionym. Neotypus. Denmark • Northwest Jutland, Salling, Skive, 56,070, 09.135 in dry grassland grazed by sheep, 28 Oct 2006, David Boertmann (voucher CFMR: DEN-21 [2006 / 70], neotype selected here) (GenBank ITS: KF 291084). UNITE / PlutoF: SH 0910871.10 FU (1.5 % threshold). Notes. Persoon (1801) preserved the specimen which he described as Agaricus irrigatus. He did not provide collection details, but it is likely that the original specimen (s) was / were collected near Göttingen or Leiden. Neither Persoon’s (1801) original description of A. irrigatus nor Fries’ sanctioning citation (Fries 1821) for A. irrigatus contained any illustrations that could constitute a holotype. Enquiries about the possible existence of any relevant specimens or drawings from Christian Persoon confirmed that none was extant at Leiden (Jorinde Nuytinck, pers. comm. Oct 2024). Similar enquiries were made at Uppsala, but no paintings or vouchers survive (Åsa Kruys, pers. comm.). At the Swedish Museum of Natural History, Stockholm there is a painting of A. unguinosus by Fries (from Sunnersta ‘ skog’ [forest], in Uppsala; https://herbarium.nrm.se/specimens/S0627) (Mats Wedin [NRM], pers. comm., Oct 2024). However, consistent with the opinion of the authors and others, we find no evidence that would suggest that G. irrigatus and G. unguinosus are separate species. As G. irrigatus has priority, the later painting of A. unguinosus by Fries cannot be considered a type for G. irrigatus. A photograph of the neotype from Northwest Jutland in Denmark by D. Boertmann is shown in Fig. 4 A and a similar collection by D. Harries in Pembrokeshire, Wales, UK (Fig. 4 B). The ITS sequence of this specimen was used as the representative of ‘ European’ G. irrigatus in phylogenetic analyses of Hygrophoraceae by Lodge et al. (2014) and was already designated the reference sequence for this species in UNITE. Distribution. Europe including the UK and southern Scandinavia according to eDNA sequences from the GlobalFungi database (Fig. 3 B) and specimen records from GBIF and sequenced specimens in the UNITE database (Fig. 3 C). Single occurrence of eDNA (singleton sequence) in far east of Canada.