Roussoellopsis macrospora (I. Hino & Katum.) I. Hino & Katum., J. Jap. Bot.

Liu, Jian-Kui, Phookamsak, Rungtiwa, Dai, Dong-Qin, Tanaka, Kazuaki, Jones, Gareth, Xu, Jian-Chu, Chukeatirote, Ekachai & Hyde, Kevin D., 2014, Roussoellaceae, a new pleosporalean family to accommodate the genera Neoroussoella gen. nov., Roussoella and Roussoellopsis, Phytotaxa 181 (1), pp. 1-33 : 25

Roussoellopsis macrospora (I. Hino & Katum.) I. Hino & Katum., J. Jap. Bot. 40(3): 87. 1965. FIG. 16

Saprobic on decaying bamboo culms. Ascostromata 0.3–0.6 mm high, 1.2–2.3 mm diam., immersed under a clypeus, raised, visible as black, dome-shaped areas on host surface, solitary to gregarious. Locules 210–280 µm high, 540–720 µm diam, depressed globose with a flattened base, single to grouped, with a central ostiole. Peridium 7–18 µm thick at sides, composed of small compressed cells, surrounded by wedge-shaped stromatic region. Hamathecium comprising 1–2 µm wide, numerous, anastomosing, hyphae-like cellular pseudoparaphyses, branching at the apex, wall rough, and embedded in a gelatinous matrix. Asci 165–220 × (17‒) 20.5–25 µm (x = 192 × 22.5 µm, n = 30), 8‒spored, bitunicate, clavate, rarely cylindrical, short to long pedicellate, apically rounded with an ocular chamber. Ascospores (27–)30–35 × 10.5–14 µm (x = 32.2 × 12.2 µm, n = 30), uni-biseriate, broadly fusiform, 2-celled, with a submedian septum, strongly constricted at the septum, brown, surrounded by mucilaginous sheath. Asexual morphs produced in culture, a “ Melanconiopsis ” or “Neomelanconium”-like conidial state is produced. Conidiomata (individual locules) 225–385 µm high, 300–430 µm diam, depressed globose, single or gregarious, immersed to erumpent, papillate at the apex. Peridium 35–70 µm thick at sides, composed of dark brown cells. Conidiophores septate, unbranched. Conidiogenous cells 13–30 × 3–6 µm, doliform to cylindrical, annellidic. Conidia 19–24.5 ×19–23 µm (x = 22.5 × 21.5 µm, n = 30), globose to subglobose, slightly truncate at the base, hyaline when immature, becoming black to dark brown when mature, thick-walled, smooth-walled.

Specimen examined THAILAND, Chiang Rai Province, Muang District, Khun Korn Waterfall , on living stem of bamboo, 21 June 2011, R . Phookamsak, RP 0126, MFLU 11–0244 , living culture MFLUCC 12–0005 .

Notes: The above material matches the original description of Didymosphaeria macrospora (Hino and Katumoto 1955) .