Agaricus fafuinus P. H. Liu & S. E. Wang, 2025
|
publication ID |
https://doi.org/10.3897/mycokeys.119.154278 |
|
DOI |
https://doi.org/10.5281/zenodo.15740438 |
|
persistent identifier |
https://treatment.plazi.org/id/5F9C3FAF-FE6A-578F-A022-5F090B7BFB5A |
|
treatment provided by |
|
|
scientific name |
Agaricus fafuinus P. H. Liu & S. E. Wang |
| status |
sp. nov. |
Agaricus fafuinus P. H. Liu & S. E. Wang sp. nov.
Figs 2 C, D View Figure 2 , 4 View Figure 4
Etymology.
Derived from the acronym FAFU (Fujian Agriculture and Forestry University), where the type specimens of this species were collected.
Holotypus.
China • Fujian Province, Fuzhou City, Fujian Agriculture and Forestry University , 4 March 2024, 26°08'N, 119°24'E, alt. 30 m, Si-Ang Chen, CSA 299 ( FFAAS 3393 ) GoogleMaps .
Diagnosis.
This species is characterized by its pileus and stipe covered with brown (7 D 5) or fox red (8 D 7) fibrils or fibrillose squamules, elongate basidiospores (Qav = 1.63), and abundant cheilocystidia.
Description.
Pileus 3.4–5.5 cm in diameter, 0.2–0.4 cm thick at the center, truncate conical to plane, surface dry, white (5 A 1), brownish gray (7 C 2), covered with brown (7 D 5) or fox red (8 D 7) fibrils or with fibrillose squamules, concentrically arranged, denser and reddish brown (8 E 8) at disc, margin appendiculate by annulus remnants. Context of the pileus, white (6 A 1), with no special odor. Lamellae 0.2–0.3 cm broad, first pastel red (9 A 4), then reddish brown (8 E 8), later brownish black (8 F 8), free, crowded, intercalated with numerous lamellulae. Stipe 2.2–4.5 × 0.6–1.5 cm, nearly cylindrical, hollow, with white (6 A 1) rhizomorphs, provided with an annulus in its upper half, above the annulus white (6 A 1), below the annulus covered towards the base with concolorous squamules with the pileus surface. Annulus superior, white (6 A 1) to reddish brown (8 E 8), simple, membranous, persistent.
Basidiospores (5.7) 6.0–7.9 (8.2) × (3.5) 3.7–5.0 (5.1) μm, [Xav = 6.8 × 4.2 μm], Q = 1.46–2.03, Qav = 1.63, ellipsoid to cylindrical, smooth, thick-walled, brown, guttulate. Basidia 17–25 × 6–9 μm, clavate, 4 (2) - spored, sterigmata 1–3 µm long. Cheilocystidia abundant, nearly globose, broadly clavate, or pyriform, 10–23 × 7–13 μm, hyaline. Pleurocystidia absent. Pileipellis a cutis of cylindrical, slightly constricted at septa, light brown hyphae, 6–12 μm wide.
Habitat and distribution.
Gregarious in bamboo forests or grass during spring. Currently, it has only been known from Fujian Province, China.
Additional specimens measured.
China • Fujian Province, Fuzhou City, Fujian Agriculture and Forestry University , 23 March 2024, Si-Ang Chen, CSA 314 ( FFAAS 3394 ) .
Notes.
Agaricus fafuinus belongs to A. (subg. Agaricus ) sect. Agaricus. Agaricus fafuinus exhibits variable pileus surface: specimen CSA 299 possesses fibrils, while CSA 314 displays fibrillose squamules. However, molecular data confirm their conspecificity, suggesting that these morphological differences may result from humidity variations. Specimen CSA 299 was collected post-rainfall and likely it was exposed to precipitation, whereas specimen CSA 314 was obtained under dry conditions. Initially, we thought we had mixed up the specimen numbers, but after thorough verification, this turned out to be accurate.
In the multi-locus phylogenetic tree (Fig. 1 View Figure 1 ), A. fafuinus and A. moellerianus Bon form a sister clade with good support. However, A. moellerianus is distinguished by its subglabrous white pileus, smooth stipe, rounder basidiospores (Qav = 1.22), and broadly clavate cheilocystidia resembling basidioles ( Kerrigan 2016).
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.
|
Kingdom |
|
|
Phylum |
|
|
Class |
|
|
Order |
|
|
Family |
|
|
Genus |