Campanophyllum microsporum Y. H. Ma, W. M. Chen & Y. C. Zhao 2024, sp. nov.
Creators: name: Ma, Yuan-Hao
name: Liu, Ping
name: Chai, Hong-Mei
name: Zeng, Min
name: Guo, Yi-Yun
name: Chen, Wei-Min
name: Zhao, Yong-Chang
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Fungi
Basidiomycota
Agaricomycetes
Agaricales
Cyphellaceae
Campanophyllum
Campanophyllum microsporum

description: Campanophyllum microsporum Y. H. Ma, W. M. Chen & Y. C. Zhao sp. nov.   
Figs 3, 4, 5  
Diagnosis.  
 Campanophyllum microsporum is characterized by dorsally pseudostipitate pileus, excentric to lateral pseudostipe, crowded lamellae, cylindrical-ellipsoid basidiospores (3.0–4.2 × 1.7–2.2 µm), narrowly clavate to clavate basidia (14.5–23.0 × 3.0–4.0 µm), and cylindrical to clavate cheilocystidia (22.0–55.0 × 5.0–11.0 µm); occurrence in a deciduous forest and solitary, cespitose, scattered, or gregarious habit on rotten wood.   
Type.  
China. Yunnan Province: Jianchuan County, Laojunshan Town (26 ° 35.85 ' N, 99 ° 40.44 ' E, elev. 3100 m), on rotten wood, 21 September 2023, Yuan-Hao Ma, Min Zeng & Wei-Min Chen (Holotype: HKAS 133170!, ex-type: YAASM 7187).  
Etymology.  
 The epithet “ microsporum ” refers to the smaller basidiospores compared to Campanophyllum proboscideum.   
Description.  
Basidiomata pseudostipitate, dorsally and eccentrically or laterally attached to substrate, occasionally central, pendent, broadly cyphelloid to crepidotoid, lamellate. Pileus 5.0–12.0 × 4.0–9.0 cm, spathulate, flabelliform to rounded-flabelliform, sometimes subcircular; plano-convex when young and applanate when older, margin inrolled, lobate when fully expanded; surface moist, initially pale orange (5 A 2–4), greyish orange (5 B 2–3), or light orange (6 A 2–5), then brownish orange (6 C 5–6), light brown (6 D 5–8), often with small stains of darker colors. Context thick, fleshy, whitish, and unchanging in color when injured. Lamellae extending radially from attachment point within pseudostipe, very crowded, sometimes forked, white to off-white, sometimes with small blackish stains. Pseudostipe 0.5–2.5 × 0.4–1.0 cm, concolorous with pileus, discolouring to blackish-ochre (6 E 5-7, 6 F 7). Spore print white. Taste mild, odor indistinct.  
 Basidiospores [149 / 7 / 4] (2.7 –) 3.0–4.2 (– 4.5) × (1.5 –) 1.7–2.2 (– 2.6) µm, L m = 3.5 µm, W m = 1.9 µm, Q = 1.4–2.5, Q m = 1.8, cylindrical-ellipsoid, smooth, hyaline, thin-walled, inamyloid. Basidia (13.5 –) 14.5–23.0 (– 26.0) × (2.3 –) 3.0–4.2 (– 4.6) µm, L m = 17.6 µm, W m = 3.6 µm, Q = 3.6–7.4, Q m = 4.9, narrowly clavate to clavate, 4 - spored, sterigma 0.9-2.2 µm. Cheilocystidia abundant, (17.5 –) 22.0–55.0 (– 59.0) × (4.2 –) 5.0–10.8 (– 13.9) µm, L m = 37.0 µm, W m = 7.2 µm, hyaline, thin-walled, mostly cylindrical to clavate, sometimes lageniform, rod-like, or beaked-utriform, pedunculate (1.9–12.5 × 1.8–4.1 µm). Pleurocystidia not observed. Lamellar trama hyaline, parallel, hyphae 3.6–17.6 µm in diameter, thin- to thick-walled. Pileipellis composed of repent, parallel hyphae, 4.2–11.5 (– 17.0) µm in diameter, sometimes with yellow-brown, intracellular pigments. Clamp connections present in all tissues of basidiomata.   
Culture characteristics. Colonies grown on YPD reaching 40 mm radius within 20 days at 22 ° C in the dark, forming abundant aerial mycelium, usually zonate. Mycelium irregularly cottony, with common clamp connections, pallid mouse gray to pale brown in aerial mycelium with age, easily forming basidiomata in the Petri plate.  
Habitat and distribution.  
Solitary, cespitose, scattered, or gregarious on rotten wood in a deciduous forest; known from Yunnan, China.  
Additional specimens examined.  
China, Yunnan Province: Jianchuan County, Laojunshan Town, 7 July 2022, Yuan-Hao Ma, Ping Liu & Yong-Chang Zhao (HKAS 133167, HKAS 133168); 26 July 2023, Yuan-Hao Ma & Ping Liu (HKAS 133169).  
Notes.  
 Campanophyllum microsporum is similar to C. proboscideum in both macro- and micro-morphology, including broadly cyphelloid to crepidotoid basidiomata, spathulate, flabelliform to rounded-flabelliform pileus, and very crowded lamellae; cylindrical-ellipsoid basidiospores, narrowly clavate to clavate basidia. However, several other features can distinguish the two species. Morphologically, the new species have smaller basidiospores (3.0–4.2 × 1.7–2.2 µm vs. 4–4.5 × 2–3 µm), slenderer and longer basidia (14.5–23.0 × 3.0–4.2 µm vs. 14–17 × 4.5–5.0 µm), and larger cheilocystidia (22.0–55.0 × 5.0–10.8 µm vs. 18–25 × 9–11 µm) (Cifuentes et al. 2003).
description: Published as part of Ma, Yuan-Hao, Liu, Ping, Chai, Hong-Mei, Zeng, Min, Guo, Yi-Yun, Chen, Wei-Min & Zhao, Yong-Chang, 2024, Campanophyllum microsporum (Agaricales, Agaricomycetes), Calocera multiramosa, and Dacrymyces naematelioides (Dacrymycetales, Dacrymycetes), three new species from Yunnan Province, southwestern China, pp. 327-350 in MycoKeys 107 on pages 327-350, DOI: 10.3897/mycokeys.107.125571