Thursday, October 29, 2026

[Fungi • 2026] Bolbitius fuscopapillatus & B. planoflavus (Agaricales: Bolbitiaceae) • Two New Species and One New Record from northeast China

 

a, b. Bolbitius titubans; f. B. coprophilus;
g, h. Bolbitius fuscopapillatus; k, l. B. planoflavus 
T. Bau & H. Cheng, 

in Cheng et Bau, 2026.
Scale bars: 1 cm.


Abstract
A taxonomic study of the genus Bolbitius from northeast China was conducted, based on morphological observations and molecular phylogenetic analyses. Phylogenetic relationships were reconstructed, based on a combined multi-locus dataset comprising the internal transcribed spacer (ITS), nuclear large subunit (nrLSU) and translation elongation factor 1-α (tef1-α) sequences. As a result, two new species are described and illustrated: Bolbitius planoflavus, characterised by its distinctly applanate, pale yellow pileus when mature and the presence of occasional 2-spored basidia; and Bolbitius fuscopapillatus, distinguished by its violet-brown papillate umbo and purplish-white margin bearing faint veil remnants. Additionally, Bolbitius bisporus is reported as a new record for China. Detailed morphological descriptions, colour photographs and comparisons with closely-related taxa are provided.

Key words: Bolbitius, multi-gene fragments, morphology, new taxa, phylogeny

Basidiomata of Bolbitius species.
 a, b. Bolbitius titubans (FJAU68133, FJAU68132); c, d. B. variicolor (FJAU68135, FJAU68134); e, f. B. coprophilus (FJAU68139, FJAU68138);
g, h. B. fuscopapillatus (FJAU68142 T, FJAU68143); i, j. B. bisporus (FJAU68137); k, l. B. planoflavus (FJAU68141, FJAU68140 T); T = holotype. White arrows in (g) indicate veil remnants, with an enlarged view shown in the upper right corner.
 Scale bars: 1 cm.


Bolbitius planoflavus T. Bau & H. Cheng, sp. nov.
 
Etymology. “planoflavus” refers to the species’ pileus being both plane and pale yellow when mature.


Bolbitius fuscopapillatus T. Bau & H. Cheng, sp. nov.
 
Etymology. From Latin fuscus (violet-brown) and papillatus (with a small papilla), referring to the violet-brown papillate umbo of the pileus.


 Hong Cheng and Tolgor Bau. 2026. Two New Species and One New Record of Bolbitius (Bolbitiaceae, Agaricales) from northeast China. MycoKeys. 140: 299-316. DOI: doi.org/10.3897/mycokeys.140.203173 [23 Sep 2026]