Tremella zhejiangensis F. Wu, L.F. Fan & Y.C. Dai, 2021

Fan, Long Fei, Pu, Jin Bao, Wu, Fang & Dai, Yu Cheng, 2021, A new species of Tremella s. s. (Tremellaceae, Basidiomycota) from southeastern China, Phytotaxa 502 (2), pp. 208-216 : 211

Tremella zhejiangensis F. Wu, L.F. Fan & Y.C. Dai , sp. nov. Figs. 2 , 3

MycoBank number: MB838848

Diagnosis:—Differs from other similar species ( T. cerebriformis and T. salmonea ) by the yellowish brown to brownish orange basidioma and smaller basidiospores, 15.0–19.0 × 14.0–17.5 μm.

Holotype:— CHINA. Zhejiang, Jinhua, Panan , on rotten trunk of Liquidambar formosana , 24 April 2020, F. Wu 346 ( BJFC033064 ).

Etymology:—Refers to the distribution of the species in Zhejiang, China.

Description:— Basidioma sessile, soft gelatinous when fresh, yellowish brown to brownish orange, irregularly cerebriform, small undulate lobes (not hollow), up to 2.8 cm long, 1.5 cm broad and 1.2 cm high from base, firmly gelatinous and brownish orange when dry, broadly attached to substrate.

Micromorphology: — Hyphae smooth, hyaline or covered by gold amorphous matter, thin-walled, 1.5–3.9 µm in diam, branched, interwoven, with abundant clamp connections; hyphidia occasionally present, unbranched, non septate, smooth, hyaline, thin-walled, 2.0–3.3 µm diam; swollen cells, haustoria and vesicles not seen; probasidia mostly globose to ovoid; mature basidia globose to subglobose or broadly ellipsoid, thin-walled, with a basal clamp connection, 27.0–38.0 × 24.0–34.0 µm, usually longitudinally septate or cruciate septate, 2–4-celled, with obvious oil drops, sterigmata up to 45.0 μm long and 4.0–6.0 μm in diam, not protuberant at apex; basidiospores hyaline, thin-walled, globose to subglobose, apiculate, with obvious oil drops, 15.0–19.0(–19.5) × 14.0–17.5(–18.0) μm, L = 17.2 µm, W = 16.06 µm, Q = 1.07–1.11 (n = 60/2), occasionally germinating by germ tubes; conidia uncertain, some cylindrical or ovoid cells (conidia-like cells) may function as conidia.

Notes:— Tremella zhejiangensis is characterized by soft gelatinous, yellowish brown to brownish orange, cerebriform basidioma when fresh, larger basidia and basidiospores than most species in Tremella s.s., and growing on rotten wood of Liquidambar formosana . Two new specimens form an independent lineage in the phylogeny ( Fig. 1 ). Additional specimen examined (isotype):— CHINA. Zhejiang, Jinhua, Panan, on rotten trunk of Liquidambar formosana , 24 April 2020, F. Wu 391 (BJFC033388).

Figures

FIGURE 1 Phylogeny of Tremella s.s. by BI analysis based on ITS (ITS1, 5.8S, ITS2) and nLSU rDNA sequences. Branches are labeled with parsimony bootstrap proportions and maximum likelihood bootstrap> 70%, and Bayesian posterior probabilities> 0.95, respectively.

FIGURE 2 A basidioma of Tremella zhejiangensis (Wu 346). Scale bar = 1.0 cm. Photo by: Jin-Bao Pu.

FIGURE 3 Microscopic structures of Tremella zhejiangensis (Wu 346). A. Basidiospores; B. Germination tubes of basidiospores; C. Conidia like cells function as conidia; D–E. Basidia at different stages; F. Hyphae with clamp connections. Scale bars = 10 µm. Photos by: Long-Fei Fan.