Aleurodiscus pinicola Sheng H. Wu

Wu, Sheng-Hua, Wei, Chia-Ling, Lin, Yu-Ting, Chang, Chiung-Chih & He, Shuang-Hui, 2019, Four new East Asian species of Aleurodiscus with echinulate basidiospores, MycoKeys 52, pp. 71-87 : 71

Aleurodiscus pinicola Sheng H. Wu sp. nov. Figs 2B, 4

Typification.

CHINA. YUNNAN PROVINCE: Lichiang, High Mountain Workstation of Kunning Botanical Garden, 27°00'N, 100°11'E, 3250 m, on branch of Pinus densata , 30 Aug 2013, S.H. Wu, Wu 1308-54 (holotype TNM F27182). GenBank: ITS = MF043525, 28S = MF043530, TEF1 = LC269191.

Etymology.

pinicola (L.), dwelling on Pinus , in reference to the substrate.

Diagnosis.

Aleurodiscus pinicola and Acanthobasidium penicillatus Burt share the features of moniliform gloeocystidia, acanthophyses with apical spines, dendrohyphidia, basidia with lateral protuberances, and aculeate basidiospores; the latter, however, has clamped hyphae and narrower basidiospores 18-27 × 12-14 (-17) μm. Aleurodiscus pinicola also resembles A. oakesii (Berk. & M.A. Curtis) Pat., however, the latter occurs on deciduous trees and has smaller basidiospores (15-20 × 13-17 μm).

Basidiomes discoid, each one up to 3.5 × 3 mm, adnate, membranaceous-subceraceous, 180-400 μm thick in section. Hymenial surface Buff or Pale Luteous, smooth, occasionally cracked; margin whitish, incurved, filamentous.

Hyphal system monomitic; most hyphae simple-septate, a few hyphal septa in junction of hymenium and subiculum with clamp connections. Subiculum uniform, with fairly dense dense texture, 60-160 μm thick; hyphae more or less vertical at resupinate parts, ± horizontal at marginal curved parts, moderately ramified, more or less interwoven, colorless, 2.5-6 μm diam, slightly thick-walled or containing thick walls up to 2 μm thick, sometimes with small oily drops, anastomoses occasional, some basal hyphae brownish yellow, with thicker walls than those elsewhere. Hymenial layer thickening, subhymenium more or less differentiated from subiculum, with dense texture, 100-270 μm thick; hyphae more or less vertical, colorless, sometimes with a short branch, usually containing minute oily drops, 2.5-5.5 μm diam, thin-walled. Crystal masses scattered throughout hymenial layer. Gloeocystidia numerous, mostly immersed or slightly projecting, cylindrical, usually strongly moniliform toward apices, usually forked, with numerous minute oily drops, colorless, 65-200 × 8.2-15.5 μm, thin- to slightly thick-walled, SA–. Acanthophyses numerous, clavate to broadly clavate, fusiform, stalked, colorless, apical parts with numerous protuberances, 50-100 × 5-30 μm, up to 1.2 μm thick walls, aculei 1-7 × 1-2 μm. Dendrohyphidia numerous, 37-90 × 3-4.8 μm. Hyphidia numerous, 35-80 × 2.4-4.2 μm. Basidia clavate, middle parts usually with several protuberances, 65-130 × 20-32 μm, up to 1.2 μm thick walls, 4-sterigmate. Basidiospores broadly ellipsoid to subglobose, adaxially flattened, aculeate, thin- to thick-walled, up to 3 μm thick walls, with a distinct apiculus, homogenous or with several oil-drops, amyloid, CB–, mostly 22.5-27.5 × 19-24 μm. (22.5 –)23.5–27.2(– 29) × (18.2 –)19.2–22.8(– 24) μm, L = 25.4 ± 1.3 μm, W = 20.7 ± 1.6 μm, Q = 1.23 (n = 30) (holotype, Wu 1308-54); (22.2 –)23–26.5(– 28) × (18.2 –)20–22.5(– 25.5) μm, L = 24.8 ± 1.3 μm, W = 21.2 ± 1.5 μm, Q = 1.17 (n = 30) (Wu 1106-14).

Ecology and distribution.

On Pinus branches at high elevations, China and Taiwan, Jun to Aug.

Additional specimens examined.

TAIWAN. Taichung, Siaosyueshan, Tienchih, 24°17'N, 121°01'E, 2580 m, on branch of Pinus armandii , 8 Jun 2011, S.H. Wu, Wu 1106-14 (TNM F25532); ibid. Wu 1106-16 (TNMF25534).