Coprinus variicolor R.L. Zhao, B. Cao & J.Xin Li, in Cao et al., Fungal Diversity 132: 509 (2025)
Index Fungorum number: IF 571924; MycoBank number: MB 571924; Facesoffungi number: FoF 17103; Figs. 1, 2
Etymology – in reference to its central veil, which changes color from grayish to orange-brown.
Holotype – HMAS 287619.
Diagnosis – this species is characterized by its veil first whitish to grayish, discolor orange-brown when mature. Basidiospores brown, thick-walled, up to 1 µm.
Pileus ovoid to ellipsoid when still closed, measuring 1.7–5 cm, up to 10.5 cm in diameter. As it matures, the margin becomes heavily revolute, and the cap surface changes from whitish to pinkish before splitting into several pieces and deliquescing, except for the center, which remains covered with a veil that transforms from grayish to orange-brown. Veil is thick and persistent, eventually breaking up into 3–5 pieces and deliquescing. Lamellae are free, crowded, and initially whitish, turning pinkish and eventually black as they deliquesce. Stipe 9–17 × 0.7–1.5 cm, whitish, cylindrical, hollow, and tapers upward, featuring a central strand and a sub-bulbous base. Annulus on lower part, up to 2 cm, fragile and fade away. Context white, later black.
Basidiospores 7.6–9.8 × 5.5–7.5 µm (Q = 1.3–1.5, n = 30), amygdaliform, ellipsoid, smooth, brownish, germ-pore central, up to 1–1.5 µm, thick-walled. Basidia 30.2–45.2 × 9.3–12.6 µm, narrow clavate, hyaline, 4-spored. Pleurocystidia not observed. Cheilocystidia 42.6–64.4 × 22.8–37.5 µm, broadly to narrowly clavate, thick-walled. hyaline. Pileipellis a cutis, 7.5–21.8 µm, composed of thin-walled, subhyaline to brown hyphae, sometimes inflate in the middle. Annulus hyphae cylindrical to inflated, chains, abundant pores present, often constricted at the septa.
Habitat – Solitary or scattered on grasslands under spruce forests.
Known distribution – China, Gansu Province.
Material examined – CHINA, Gansu Province, Zhangye City, Yanzhishan, 20 August 2017, collected by Ming-Zhe Zhang, QL20170168 (HMAS 282432), QL20170169 (HMAS 282433); Gansu Province, Zhangye City, Matisi, 17 August 2018, collected by Bin Cao, ZRL20181059 (HMAS 282434); Gansu Province, Wuwei City, Wushaoling Protection Station, Chashugou, 20 August 2018, collected by Zhi-Lin Ling, ZRL20181072 (HMAS 287619, holotype) and ZRL20181073 (HMAS 282435); Gansu Province, Wuwei City, Sharma Protection Station, shimenxia, 21 August 2018, collected by Bin Cao, ZRL20181337 (HMAS 282436).
GenBank – HMAS 287619: PP718938 (ITS); HMAS 282432: PP718935 (ITS); HMAS 282433: PP718934 (ITS); HMAS 282434: PP718936 (ITS); HMAS 282435: PP718937 (ITS); HMAS 282436: PP718935 (ITS).
Notes – Coprinus variicolor is characterized by its color changing veil, which transitions from grayish to orange brown as it matures, as well as its dark brown, thick-walled basidiospores with a central germ pore. Phylogenetic analysis reveals that C. variicolor, C. roseistipitatus, C. palmeranus, and C. pinetorum form a well-supported clade at the base of the tree (Fig. 2). However, these species exhibit distinct variations in the ITS region. Specifically C. variicolor differs by 2 base pairs (bp) in ITS sequences from C. pinetorum and C. roseistipitatus, and by 4 bp from C. palmeranus. These species can be distinguished by other characteristics. Coprinus roseistipitatus, originally described from Washington State by Van De Bogart (1976), fruits on dung. In contrast, C. pinetorum closely resembles C. variicolor but has a thick, persistent veil that remains grayish to orange-brown. Additionally, C. pinetorum has narrower basidiospores (Q = 1.38–1.62) and smaller basidia (14–35 × 10–13 µm) (Crous et al. 2016b). Coprinus palmeranus is distinguished by its globose to subglobose, ellipsoid, ovoid, oblong, or utriform cheilo cystidia (25–50 × 14–26 µm) (Uljé and Noordeloos 2001).
Figure 1 – Coprinus variicolor (HMAS 287619, holotype). a–c Basidiomata in field. d Basidia. e Basidiospore. f Cheilocystidia. g Veil on the pileus. h Element on the pileus. Scale bars: a, c = 1 cm, b = 2 cm, d, g, h = 10 µm, e = 5 µm, f = 20 µm.
Figure 2 – Maximum Likelihood tree of Coprinus and Montagnea inferred from ITS sequences data, rooted with Phellorinia longis triatica, Dictyocephalos xinjiangensis and Tulostoma calcareum. Branches supported by both BS = 70% and PP = 0.90 were labeled. The examined specimens in this study are bolded.