Coniophoropsis bambusicola S.H. He & Nakasone, 2018

Zhao, Ya-Nan, Liu, Shi-Liang, Nakasone, Karen K. & He, Shuang-Hui, 2018, Coniophoropsis bambusicola sp. nov. (Coniophoraceae, Basidiomycota) from southern Vietnam, Phytotaxa 360 (2), pp. 153-160 : 157-158

Coniophoropsis bambusicola S.H. He & Nakasone , sp. nov. ( Figs. 2–4 )

MycoBank: MB 824360

Diagnosis:—The species differs from C. obscura by having much smaller basidiospores measuring 5.5–7 × 4–5 μm.

Type:— VIETNAM. Thac Mai Preservation Park, lowland rain forest Dipterocarp, on culm of dead bamboo, 14 October 2017, He 5208 (BJFC 024726, holotype).

Etymology:— “ bambusicola ” (Lat.) refers to growing on bamboo.

Description:— Basidiocarps annual, resupinate, effused, closely adnate, inseparable from substrate, coriaceous to crustose, first as irregular small patches, later confluent up to 20 cm long, 4 cm wide, 50–180 μm thick. Hymenophore surface smooth, greyish brown [6(D–F)3], brown [6E(4–8)] to dark brown [6F(4–8)], not cracked; margin thinning, indeterminate, indistinct, concolorous or slightly darker than hymenophore surface. Hyphal system monomitic. Subiculum very thin to absent. Subhymenium thickening, yellowish brown; generative hyphae in this layer simple-septate, without verticillate clamps, hyaline to mostly yellowish brown, thin- to thick-walled, with a wide lumen, densely interwoven, agglutinated, frequently branched and septate, 2–4 μm in diam. Cystidia abundant, ventricose, slightly thick-walled, 18–25 × 8–10 μm. Dendrohyphidia numerous, hyaline, thin- to slightly thick-walled, usually torulose. Basidia subcylindrical to suburniform with a distinct median constriction, tapering toward the base, thinwalled or slightly thick-walled at the base, hyaline, with four sterigmata and a basal simple septum, 32–40 × 5–8 μm; basidioles similar to basidia but smaller. Basidiospores subfusiform to ellipsoid, with an apiculus, hyaline to pale yellow, thick-walled, verrucose, without color change in Melzer’s reagent, cyanophilous, 5.5–7 (–7.5) × 4–5 (–5.5) μm, L = 6.3 μm, W = 4.7 μm, Q = 1.3 (n = 30/1).

Additional specimen examined:— VIETNAM. Thac Mai Preservation Park, lowland rain forest Dipterocarp, on culm of dead bamboo, 14 October 2017, He 5210 (BJFC 024726).

Remarks:— Coniophoropsis bambusicola is characterized by having thin, brown resupinate basidiocarps with a smooth hymenophore, simple-septate generative hyphae, ventricose cystidia, hyaline dendrohyphida, ellipsoid, thick-walled and verrucose basidiospores, and growing on bamboo in the tropics. It is the second species in the genus. Coniophoropsis obscura , the generic type, can be easily distinguished from the C. bambusicola by having much larger basidiospores (15–18 × 7.5–9 μm), the absence of cystidia and a distribution in South America ( Hjortstam & Ryvarden 1986). In the ITS-28S phylogenetic tree of Boletales , Coniophoropsis bambusicola and the Coniophora species formed a fully supported clade ( Fig. 1 ). However, morphologically Coniophoropsis can be easily distinguished from Coniophora by having ornamented and non-dextrinoid basidiospores, and absence of verticillate or scattered clamps on the basal hyphae ( Ginns 1982, Hjortstam & Ryvarden 1986).

Figures

FIGURE 1. Phylogenetic tree inferred from maximum parsimony analysis based on the combined dataset of ITS and 28S sequences of Boletales species. Branches are labelled with maximum parsimony bootstraps ≥ 50% and Bayesian posterior probabilities ≥ 0.95.

FIGURE 2. Basidiocarps of Coniophoropsis bambusicola (He 5208, holotype). Bar: 1 cm. Photos by Shuang-Hui He.

FIGURE 3. Microscopic structures of Coniophoropsis bambusicola (from the holotype). a. Basidiospores. b. Basidia. c. Basidioles. d. Gloeocystidia. e. Dendrohyphidia. Bars: 10 μm. Drawings by Shi-Liang Liu.

FIGURE 4. Scanning electron microscope (SEM) of a basidiospore of Coniophoropsis bambusicola (from the holotype). Bar: 1 μm. Photos by Shi-Liang Liu.