Clavariadelphus ligula (Schaeff.) Donk, Rev. Niederl. Homob. Aphyll. 2: 73, 1933

Huang, Hong-Yan, Zhao, Jie, Zhang, Ping, Ge, Zai-Wei, Li, Xian & Tang, Li-Ping, 2020, The genus Clavariadelphus (Clavariadelphaceae, Gomphales) in China, MycoKeys 70, pp. 89-121 : 89

7. Clavariadelphus ligula (Schaeff.) Donk, Rev. Niederl. Homob. Aphyll. 2: 73, 1933 Figs 3g , 12a, b

Note.

The following taxonomic description is drawn from Methven (1990) and our observations.

Description.

Basidiomes up to 10 cm high, 0.2-0.8 cm diam. basally, slightly enlarged upwards, simple, narrowly clavate to clavate; hymenium longitudinally rugose in age, light yellow, brownish-orange to light brown at maturity; apex subacute to obtuse or broadly rounded, surface slightly rugulose, concolorous with the hymenium; surface slowly staining brownish-orange to brownish-grey where cut or bruised; base terete, initially pale yellow to light yellow, then brownish-orange to light brown to brown; mycelial hyphae white to pallid; flesh initially solid, becoming soft and spongy upwards as the apex enlarges in age, white to pallid. Odour not distinctive. Taste not distinctive or slightly sweet. Spore deposit yellowish-white to light buff in mass.

Hymenium extending over the apex of basidiomata, composed of basidia and leptocystidia. Basidia 45-85 × 8-11 μm, clavate, hyaline, thin-walled, 4-spored, sterigmata 9-10 μm in length. Basidiospores 11.0-14.0 × 4.0-5.5 μm, Q = 2.4-3.1, Q m = 2.7, narrowly ellipsoid, with a small apiculus, inamyloid, thin-walled, hyaline in KOH, smooth. Leptocystidia 40-80 × 2.5-5 μm, scattered amongst and scarcely projecting beyond the basidia, cylindrical to narrowly clavate, thin-walled, smooth, hyaline, non-pigmented, clamped, inflated apically at maturity, at times with apical or subapical branches. Mycelial hyphae 2-4 μm diam., interwoven or aggregated into rhizomorphic strands, branched, clamped. Insufficient material to perform SEM.

Chemical reactions.

(dried basidiomes): KOH = positive, lemon-chiffon; NH4OH = positive, orange; ethanol, FeCl3, FeSO4, Melzer’s reagent and phenol = negative.

Known distribution and ecology.

Widespread in the Northern Hemisphere, including in North America, Bulgaria, NE China, England, Estonia, Finland, Germany, India, Italy, Sweden and Switzerland ( Methven 1990). Scattered to gregarious habit on the ground in mixed woods ( Abies , Picea , Pinus , Thuja and Tsuga ).

Materials examined.

China. Heilongjiang Province: Linkou Prefecture, 19 August 1972, X.L. Mao, s. n. (HKAS 35954); same location, Q.X. Wu, s. n. (HMAS 51688). Czech: 2 September 1960, M. Geesteranus 13290 (HMAS 41146).

Comments.

Clavariadelphus ligula was originally described from Germany, but was also reported in China ( Mao 2009). Our study confirms that this species is mainly found in N China, whereas our data do not support the previous report of the distribution in SW China ( Mao et al. 1993; Mao 2009). The basidiospores of Chinese collections (11.0-14.0 × 4.0-5.5 μm, Q = 2.4-3.1, Q m = 2.7) are smaller and broader than the neotype of C. ligula from Germany (12.0-16.5 × 3.5-4.5 μm, Q = 2.9-4.6, Q m = 3.7; Methven 1990).

Morphologically, C. ligula and C. sachalinensis are similar in the field. However, C. sachalinensis has more elongated, narrower basidiospores (21-24 × 4-6 μm, Q = 3.5-5.0, Q m = 4.2). Additionally, C. ligula lacks any reaction with FeCl3, whereas C. sachalinensis turns green-yellow in FeCl3. Clavariadelphus yunnanensis is likely to be confused with C. ligula when young. However, C. yunnanensis differs in that it has larger basidiomes (up to 20 cm high), smaller and broader basidiospores (9.0-11.0 × 4.6-6.4 μm, Q = 1.32-1.72, Q m = 1.56) and a positive reaction with phenol.

The phylogenetic analyses show that C. ligula is allied with the sequence of C. americanus from GenBank with strong support (Fig. 1 ).

Figures

Figure 1. Phylogenetic tree of Clavariadelphus based on ITS sequence data. RAxML BP values (≥ 50 %) are shown above branches, Bayesian posterior probabilities (≥ 0.90) are shown above branches; new taxa are marked in red.

Figure 3. Basidiospores of Clavariadelphus under light microscope. a C. alpinus (HKAS 57396, holotype) b C. amplus (HKAS 54876, holotype) c C. elongatus (HKAS 76589) d C. gansuensis (HKAS 76487, holotype) e C. himalayensis (HKAS 58811) f C. khinganensis (MHHNU 7789, holotype) g C. ligula (HKAS 35954) h C. sachalinensis (MHHNU 7816) i C. yunnanensis (HKAS 57659).

Figure 12. Microscopic features of Clavariadelphus ligula (HMAS 35954). a Leptocystidia and immature basidia b Basidia.