Crepidotus cinereofuscus T. Z. Liu, X. P. Yang & T. Z. Wei, 2025

Yang, Xiaopo, Han, Menghui, Wei, Tiezheng & Liu, TieZhi, 2025, New Crepidotus (Agaricales, Crepidotaceae) findings in China: Crepidotus cinereofuscus sp. nov. and record of C. stenocystis, Biodiversity Data Journal 13, pp. e 153245-e 153245 : e153245-

Crepidotus cinereofuscus T. Z. Liu, X. P. Yang & T. Z. Wei sp. nov.

Materials

Type status: Holotype. Occurrence: occurrenceID: B32B0132-CF15-59A3-A87C-47869FB3D0F6; Taxon: kingdom: Fungi; phylum: Basidiomycota; class: Agaricomycetes; order: Agaricales ; family: Crepidotaceae ; genus: Crepidotus ; subgenus: Dochmiopus ; taxonRank: species; Location: country: China; stateProvince: Inner Mongolia Autonomous Region; county: Chifeng City; verbatimLocality: Chifeng University; verbatimElevation: 585 m; verbatimLatitude: 42°14′33″N; verbatimLongitude: 118°54′40″E; Identification: identifiedBy: TieZhi Liu; Event: year: 2022; month: July; day: 7; Record Level: institutionID: CFSZ; collectionID: CFSZ 24821

Type status: Other material. Occurrence: occurrenceID: C95E606E-E92A-5F10-9847-394B136EB38C; Taxon: kingdom: Fungi; phylum: Basidiomycota; class: Agaricomycetes; order: Agaricales ; family: Crepidotaceae ; genus: Crepidotus ; subgenus: Dochmiopus ; taxonRank: species; Location: country: China; stateProvince: Inner Mongolia Autonomous Region; county: Chifeng City; verbatimLocality: Chifeng University; verbatimElevation: 583 m; verbatimLatitude: 42°14′33″N; verbatimLongitude: 118°54′40″E; Identification: identifiedBy: TieZhi Liu; Event: year: 2022; month: July; day: 7; Record Level: institutionID: CFSZ; collectionID: CFSZ 24838

Type status: Other material. Occurrence: occurrenceID: 55CCEAEB-ECD8-599B-975F-6C14047D92AF; Taxon: kingdom: Fungi; phylum: Basidiomycota; class: Agaricomycetes; order: Agaricales ; family: Crepidotaceae ; genus: Crepidotus ; subgenus: Dochmiopus ; taxonRank: species; Location: country: China; stateProvince: Shandong Province; county: Tai’an City; verbatimLocality: Taishan Natural Sight; verbatimElevation: 1473 m; Identification: identifiedBy: Menghui Han, Renxiu Wei, and Qin Na; Event: year: 2023; month: August; day: 17; Record Level: institutionID: FFAAS; collectionID: FFAAS 0367

Description

Pileus 10–35 mm, attached laterally, sometimes dorsally to the substratum, ungulate to conchoid when young, * Lavender Grey (XLIII 49 ''' f) to Greyish Lavender (XLIII 57 ''' f), when mature flabelliform, semicircular to petaloid, plane, at the centre Dark Slate-Violet (1) (XLIII 7 ''' k), Deep Purplish Grey (LIII 67 ''''' i) to Light Neutral Grey (LIII NEUTRAL GREY b), gradually paler from centre to margin, margin White (LIII), margin incurved and glabrescent in all stages; pubescence white, dense near the point of attachment, gradually sparse towards the edge when young, when mature, few and scattered, more or less forming scales; dry, not hygrophanous, non-striated; Lamellae 15–25 mm, L = 9–16, l = 1–7, adnexed to adnate, subventricose, edge smooth; White (LIII) when young, becoming Ivory Yellow (XXX 21 '' f) to Brownish-Olive (XXX 19 '' m), darker in the centre and paler to the margin when mature. Stipe present, cylindrical, at times as a lateral knob or covered by lamellae. Context thin (<5 mm thick), but thicker near the stipe, White (LIII). Odour and taste not distinctive (Fig. 1 ).

Basidiospores [167 / 3 / 2] (6.9) 7.4–8.0 – 8.7 (9.3) × (4.3) 4.5–4.8 – 5.4 (5.8) μm, Q = (1.52) 1.55–1.76 (1.86), Q m = 1.66 ± 0.065, [HOLOTYPE [128 / 2 / 1] (7.1) 7.6–8.0 – 8.6 (9.3) × (4.3) 4.5–4.8 – 5.4 (5.8) μm, Q = (1.52) 1.56–1.76 (1.78), Q m = 1.66 ± 0.064], ellipsoid to oblong in lateral view, ellipsoid to ovoid in frontal view, yellow to ochre in 5 % KOH aqueous solution, smooth, slightly thick-walled, sometimes with granular contents (under oil). Basidia 24–32 × 7.2–8.7 μm, clavate, 4 – spored, rarely 2 – spored, sterigmata 2.2–5.2 μm long, thin-walled (<0.5 μm thick), hyaline. Pleurocystidia absent. Cheilocystidia 31–50 × 6.8–15.7 μm, clavate, apex rounded, occasionally segmented and bifurcate, middle portion more or less ventricose, constricted to base, hyaline, thin-walled (<0.5 μm thick). Pileipellis a rectocutis, composed of densely arranged cylindrical hyphae, parallel, 4.1–6.7 μm wide, thin- to thick-walled (0.3–0.9 μm), grey extracellular pigment deposits are present in the upper layer, a few hyphae encrusted, non-gelatinised. Lamellae trama subregular, composed of subparallel cylindrical hyphae, 7–15 μm diam., subregular, non-gelatinised. Clamp connections present in all tissue (Figs 2 , 3 ).

Diagnosis

Pileus dusky grey to purplish-grey, covered with white pubescence, more or less forming scales, not hygrophanous, non-striated; basidiospores ellipsoid to oblong, smooth, clamp connections present. Differs from C. occidentalis Hesler & A. H. Sm. by dusky grey to purplish-grey pileus, lamellae edge smooth and wider cheilocystidia.

Etymology

The epithet “ cinereofuscus ” combines the Latin adjective “ cinereus ” and “ fuscus ”. This name describes the colour of the pileus, which is dusky grey to purplish-grey.

Ecology

Solitary or scattered on soil or soil-covered rock surface.

Notes

According to the classification proposed by Consiglio and Setti, C. cinereofuscus is classified into C. subg. Dochmiopus sect. Autochthoni , based on its smooth basidiospores and the presence of clamp connections ( Consiglio and Setti 2008). This section currently comprises seven species: C. autochthonus J. E. Lange , C. wasseri Kapitonov, Biketova, Zmitr. & Á. Kovács , C. novae-zealandiae Pilát , C. tortus A. M. Kumar & C. K. Pradeep , C. trichocraspedotus T. Bau & Y. P. Ge , C. occidentalis and C. lamellomaculatus M. H. Han, Q. Na, Y. P. Hu & Y. P. Ge. Amongst these, only C. occidentalis and C. autochthonus exhibit a slightly grey pileus, while the remaining species are characterised by white to pale yellow pileus, clearly distinguishing them from C. cinereofuscus , which has a silver-grey to pale brownish-grey pileus ( Hesler and Smith 1965, Senn-Irlet 1995, Consiglio and Setti 2008). Additionally, C. occidentalis differs from C. cinereofuscus by its fimbriated lamellae edge, wider cheilocystidia and a cutis pileipellis composed of long, straight and slender hyphae ( Hesler and Smith 1965, Krisai-Greilhuber et al. 2002). C. autochthonus can be distinguished by its gelatinised pileipellis and cream-white, light yellow to silvery-grey pileus, which is lighter in colour than that of C. cinereofuscus ( Consiglio and Setti 2008, Ge 2017). Amongst the remaining five species, C. cinereofuscus can be readily differentiated not only by its distinct pileus colouration, but also by its microscopic characteristics. Microscopically, C. wasseri and C. lamellomaculatus possess narrowly lageniform cheilocystidia with ventricose middle part, whereas C. tortus and C. trichocraspedotus exibit irregularly strangulated, vine-shaped cheilocystidia ( Ge and Bau 2020, Kapitonov VI 2021, Kumar et al. 2022, Han et al. 2024). The pileipellis of C. wasseri and C. trichocraspedotus are a trichoderm, C. lamellomaculatus is a tomentum, C. tortus is a cutis, while C. cinereofuscus is a rectocutis pileipellis ( Ge and Bau 2020, Kapitonov VI 2021, Kumar et al. 2022, Han et al. 2024). In addition, C. novae-zealandiae has a gelatinised pileus and a fimbriated lamellae edge, whereas C. cinereofuscus lacks gelatinisation and possesses a smooth lamellae edge ( Horak 2018). Phylogenetically, C. cinereofuscus is closely related to C. iqbalii A. Izhar, Usman & Khalid and C. subfulviceps (Murrill) Aime, Vila & P. - A. Moreau. However , both C. iqbalii and C. subfulviceps can be clearly distinguished by their distinct stipe and yellow coloured pileus, contrasting with the sessile, silver-grey to pale brownish-grey pileus of C. cinereofuscus .

The specimen FFAAS 0367, collected from Shandong Province, differs from those collected in the Inner Mongolia Autonomous Region by its basidiospores dimensions. The basidiospores of FFAAS 0367 are (6.7) 6.9–7.7 – 8.5 (8.8) × (4.7) 4.8–5.3 – 6.1 (6.2) μm, Q = (1.33) 1.36–1.55 (1.58), Q m = 1.45 ± 0.065, narrower than the Inner Mongolia Autonomous Region specimens. Nevertheless, based on the phylogenetic analyses and morphological characteristics, we consider the specimens from Shandong Province and Inner Mongolia Autonomous Region to represent the same species. Given the comparatively more humid climate of Shandong Province and the observation that the Shandong specimen appeared to be at an earlier developmental stage, we hypothesise that climatic conditions and developmental stages may influence basidiospore dimensions. Further, more specimens from diverse regions are required to substantiate this hypothesis.

Figures

Figure 1. Fresh basidiomata of Crepidotus cinereofuscus sp. nov. Bars: a – c = 10 mm. Photos by Tiezhi Liu.

Figure 2. Microscopic features of Crepidotus cinereofuscus (CFSZ 24821, Holotype). a – f Lateral view of basidiospores; g, h Basidia; i – r Cheilocystidia; s Lamellae trama; t Pileipellis. Bars: a – f = 5 μm; g – h = 10 μm; i – r = 20 μm; s – t = 50 μm. Structures on a – f were rehydrated in 5 % KOH aqueous solution and g – t were stained in 1 % Congo red aqueous solution. Anatomical examination by Menghui Han.

Figure 3. Morphological features of Crepidotus cinereofuscus (CFSZ 24821, Holotype). a Basidiomata; b Basidiospores; c Basidia; d, e Cheilocystidia; f Pileipellis. Bars: a = 10 mm; b = 5 μm; c – e = 10 μm; f = 20 μm. Drawing by Menghui Han.