Odontia sparsa Yuan Yuan, Y. C. Dai & H. S. Yuan 2018, sp. nov.
Creators: name: Yuan, Yuan
name: Wu, Fang
name: Dai, Yu-Cheng
name: Qin, Wen-Min
name: Yuan, Hai-Sheng
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Fungi
Basidiomycota
Agaricomycetes
Thelephorales
Thelephoraceae
Odontia
Odontia sparsa

description: Odontia sparsa Yuan Yuan, Y.C. Dai & H.S. Yuan, sp. nov. Figs. 5–7   
MycoBank no.: MB 823886.  
 Type:— CHINA. Liaoning Province, Kuandian County, Baishilazi Nature Reserve, on fallen angiosperm branch, 22.X.2015 Yuan 10780 (IFP, holotype).   
Etymology:— “sparsa ” (Lat.), referring to hymenophoral surface with sparsely distributed spines.  
 Diagnosis:—Differs from Odontia ferruginea by having clamp connections on generative hyphae only in spine trama and simple-septate generative hyphae in rhizomorphs.   
 Description:— Basidiocarps annual, resupinate, easily separable from the substrate, arachnoid, continuous, without odor or taste when fresh, becoming cottony upon drying, up to 0.5 mm thick. Hymenophoral surface brown (6E6–6E8) when dry, smooth or hydnoid to the naked eye; spines conical, up to 0.8 mm long and 0.15–0.2 mm wide at the base, evenly distributed, 1–2 per mm, concolorous with subiculum. Subiculum brown. Sterile margin indeterminate, byssoid, concolorous with hymenophore. Rhizomorphs present in subiculum and margins, 20–60 μm diam; rhizomorphic surface rather smooth; hyphal structure in rhizomorph dimitic, differentiated, of type C (according to Agerer 1987 –2008), compactly arranged; generative hyphae in center of rhizomorph simple-septate, slightly thick-walled, 3–4.5 μm diam, colorless in KOH; skeletal hyphae at outer part of rhizomorph thick-walled, 1.2–1.8 μm diam, grayish yellow in KOH, cyanophilous, inamyloid.   
 Hyphal structure subicular hyphae dimitic, generative hyphae with clamp connections, thin-walled, 3–5 μm diam, occasionally collapsed, rarely branched, scarcely encrusted, grayish yellow in KOH; skeletal hyphae thick-walled, 1–2 μm diam, grayish yellow in KOH, acyanophilous, inamyloid. Subhymenial hyphae with clamp connections, thin-walled, 2–5 μm diam; hyphal cells more or less uniform, grayish yellow in KOH, cyanophilous, inamyloid. Spine tramal hyphae dimitic, generative hyphae with clamp connections, 2–3.5 μm diam, thin-walled, grayish yellow in KOH; skeletal hyphae thick-walled, 1–1.5 μm diam, grayish yellow in KOH, cyanophilous, inamyloid.   
 Hymenium cystidia and cystidioles absent. Basidia 12–20 μm long and 6–10 μm diam at apex, 3–5 μm at base, with a clamp connection at base, clavate, not stalked, not sinuous, rarely with transverse septa, grayish yellow in KOH and in distilled water, 4 sterigmata; sterigmata up to 5 μm long, 0.5–1 μm diam at base. Basidiospores 6.3–8.5(–8.7) × 5.2–7.6 μm in lateral and frontal face, L = 7.38 μm, W = 6.60 μm, Q = 1.11–1.18 (n = 60/2), irregular globose frontal and ellipsoid lateral face, oildrops absent, verruculose, reddish brown in KOH, brownish yellow in distilled water, acyanophilous, inamyloid; warts usually grouped in 2 or more, bi- or trifurcate, alike in shape, 0.3–0.8 μm long. Chlamydospores absent.   
 Additional specimen (paratype) examined:— CHINA. Liaoning Province, Kuandian County, Baishilazi Nature Reserve, on fallen angiosperm branch, 22 October 2015 Yuan 10718 (IFP).
description: Published as part of Yuan, Yuan, Wu, Fang, Dai, Yu-Cheng, Qin, Wen-Min & Yuan, Hai-Sheng, 2018, Odontia aculeata and O. sparsa, two new species of tomentelloid fungi (Thelephorales, Basidiomycota) from the secondary forests of northeast China, pp. 183-192 in Phytotaxa 372 (3) on pages 189-191, DOI: 10.11646/phytotaxa.372.3.1, http://zenodo.org/record/13728698