Panaeolus (Bresadolomyces) M. Q. He & R. L. Zhao, subg. nov.

Panaeolus subg. Bresadolomyces M. Q. He & R. L. Zhao subg. nov. Diagnosis. Species of this subgenus have relatively thin-fleshed, dirty whitish or gray to grayish-brown pigmented basidiome, some species turning blue or bluish-gray when get injured; basidiospores smooth, ellipsoid, limoniform, cruciform-rhomboid. Type species. Panaeolus cyanescens Sacc. Etymology. Named in honor of Giacomo Bresàdola (1847–1929) for his research contributions to agarics taxonomy and introduction of Copelandia. Synonyms. Copelandia Bres., Hedwigia 53 (1–2): 51 (1912) [1913] (nom. illeg., Shenzhen Code, Art. 52.1); Panaeolus subgen. Copelandia (Bres.) Ew. Gerhardt, Biblioth. Bot. 147: 32 (1996) (nom. illeg., Art. 52.1). – Type: Copelandia papilionacea (Bull.) Bres., Hedwigia 53 (1–2): 51 (1912) [1913] (nom. inval., Art. 35.1); Crucispora E. Horak, New Zealand J. Bot. 9 (3): 489 (1971). Description. Basidiome relatively thin-fleshed, dirty whitish or gray to grayish-brown pigmented, some species turning blue or bluish-gray when cut or bruised; the cap surface not slimy; basidiospores smooth, ellipsoid, limoniform, or cruciform-rhomboid; the hymenium always contains thick-walled pseudocystidia (metuloids) that often secrete crystals at the tip. Notes. The synonym name subg. Copelandia was proposed with the type P. papilionaceus (Gerhardt 1996). However, P. papilionaceus had already been designated as the type of Panaeolus subg. Panaeolus by Quélet (1872). According to the Shenzhen Code, Art. 52.1, Panaeolus subg. Copelandia is illegitimate. Subgenus Bresadolomyces is proposed mainly based on phylogenetic evidence to accommodate Copelandia - like species and species formerly placed in Crucispora. Copelandia - like species cluster together with Cr. rhombisperma in clade C, which is well supported statistically (SH-aLRT / PP = 96 / 1.0). Copelandia - like species are mainly characterized by grayish, relatively fragile basidiomes that turn blue when injured or bruised. They represent the main psilocybin-producing group within Panaeolus, with the most well-known species being P. cyanescens. Species included. P. axfordii Y. W. Hu, Karun., P. E. Mortimer & J. C. Xu, P. bisporus, P. cyanescens (Guzmán) Voto & Angelini, P. mexicanus, P. rhombispermus (Hongo) Birkebak, Voto & Ostuni.