Trechispora tongdaoensis P. Zhang & P.T. Deng, 2023

Deng, Peng-Tao, Yan, Jun, Liu, Xiang-Fen, He, Zheng-Mi, Lin, Yuan, Lu, Ming-Xin & Zhang, Ping, 2023, Three coralloid species of the genus Trechispora (Trechisporales, Basidiomycota) in China: two newly discovered taxa and one reported for the first time, MycoKeys 99, pp. 153-170 : 153

Trechispora tongdaoensis P. Zhang & P.T. Deng sp. nov.

Figs 8 , 9 , 10

Diagnosis.

Differs from Trechispora termitophila by the white fruiting body and 4-spored basidia.

Type.

China, Hunan Province, Tongdao County, WanFo Mountain Nature Reserve , 26°32′54″N, 109°86′95″E, 523 m asl., 6 July 2022, leg. P. Zhang (holotype MHHNU11083) .

Etymology.

Trechispora tongdaoensis (Latin), referring to the currently known distribution of the species in Tongdao County, Hunan Province, China.

Basidiomata.

Clavarioid, gregarious to caespitose clusters, 60-90 mm tall, 30-45 mm broad, white (1A1), with pale yellow (1A3). Stipe single, 20-40 mm long, white (1A1), no change in color when dried. Branches dense, branching from the base, repeatedly dichotomous towards apices, divided 3-5 times, branches slender, 2-3 mm wide, internodes becoming gradually longer, terminal branches long and not flat, sometimes split at the tips, acute, axils V-shaped, terminal branches short, tips acute. Context pale yellow. Taste and odor not recorded.

Micromorphology.

Context hyphae compact, 3-5.5 μm wide, subparallel arranged, cylindric; generative hyphae with clamp connections but not at every septum, thin-walled, smooth, hyaline, no calcium oxalate crystals; ampullate septa present in the hyphae of the stipe, 7-8 µm wide. Basidia: approximately 18-28 × 6-8 µm with four sterigmata 3-5 µm long, hyaline, subclavate to cylindrical, with clamp connection in base. Cystidia absent. Basidiospores [40/3/2] 4-6(6.5) × 3-5.5 μm [Q = 1.25-1.57(1.83), Qm = 1.50 ± 0.11] ellipsoid, slightly angular, tuberculate or coarsely echinulate, spines 0.5-1 μm long, blunt; hilar appendage ambiguous by spore ornamentation, sometimes contents uniguttulate, inamyloid.

Habit and distribution.

Caespitose or gregarious on the soil of broadleaf forests; basidiomata generally occur in summer. Known only from the type locality in China.

Notes.

The fruiting body of T. tongdaoensis has a long stalk, 20-40 × 4-6 mm, the terminal branches are long, bifurcate, the tips are white, and the branches are not flattened in a plane. Trechispora foetida differs from T. tongdaoensis by having reddish brown to deep brown basidiomata, and flattened branches and stipe. Trechispora caulocystidiata has cystidia in the stipitipellis as caulocystidial hairs. This feature is obvious under a microscope, but we failed to observe this structure in T. tongdaoensis . In addition, the T. caulocystidiata stipe is relatively shorter (10-20 × 3-5 mm vs. 20-40 × 4-6 mm in T. tongdaoensis ). Trechispora copiosa differs from T. tongdaoensis in having acute or flattened branch tips and T. tongdaoensis has relatively smaller spores (4-6 (-6.5) × 3-5.5 μm vs. (5-) 5.5-6.5 (-7) × (3-) 3.5-4 (-4.5) μm in T. copiosa ). Trechispora dealbata was classified in Ramariopsis (Donk) Corner based on the gelatinous context by Petersen (1984, 1988), whereas T. tongdaoensis lacks a gelatinous context and differs in having relatively smaller spores (4.0-4.5 × 2.5-3.5 µm vs. 4-6(6.5) × 3-5.5 μm in T. tongdaoensis ). In the field, T. gelatinosa has a fleshy or gelatinous consistency, translucent when fresh, small basidia (12-26 × 5-6.5 μm), and small basidiospores (3-) 3.2-4.5 (-5) × (2-) 2.5-3.5 (-4) μm, which distinguishes the species from T. tongdaoensis . In the present phylogenetic analyses, T. tongdaoensis clustered with pigmented species.

Figures

Figure 8. Basidiomata of Trechispora tongdaoensis (MHHNU 11083). Scale bars: 1 cm.

Figure 9. Microscopic features of Trechispora tongdaoensis (MHHNU 11083) a Basidiospores b Basidia.

Figure 10. Scanning electron micrograph of basidiospores of Trechispora tongdaoensis (MHHNU 11083).