Neokalmusia brevispora(Nagas. & Y. Otani) Kaz. Tanaka, Ariyawansa& K. D. Hyde, in Ariyawansa, Tanaka, Thambugala, Phookamsak, Tian & Campo, Fungal Diversity 68: 92 (2014)

Basionym: Phaeosphaeria arundinacea var. brevispora Nagas. & Y. Otani, Rep. Tottori Mycol. Inst. 15: 38 (1977).

Index Fungorum number: IF 550701; MycoBank number: MB 550701; Facesoffungi number: FoF 00051

Saprobic on culms of Sasa spp. Sexual state: Ascomata 200–370(–400) × 190–330(–440) μm immersed under black clypeus-like structure composed of host epidermis and fungal mycelium, scattered to grouped, subglobose to oblong on host surface, 1–3.5 mm long, 0.4–0.7 mm wide. Ostiole absent or short papillate, 50–75(-110) μm long, with hyaline periphyses. Peridium 15–20 μm diam., composed of 2- layers, outer layer composed of 2–4 layers, light brown to dark brown pseudoparenchymatous cells of textura angularis, inner wall consists of 1–2 layers, hyaline cells of textura angularis. Hamathecium of 1.5–2.5 μm dense thick, cellular, hyaline, septate pseudoparaphyses. Asci 80–118 × 10.5–15 μm (= 100.2 × 13.4 μm, n = 32), 4–8-spored, cylindrical to clavate, bitunicate, fissitunicate, with a 10–25(–30) μm (= 19.8 μm, n = 30) a short pedicel. Ascospores 18–24(-26.5) × 4–7 μm (= 20.1 × 5.2 μm, n = 76), uniseriate or partially overlapping, fusiform, 3-septate, with a mostly submedian (0.48–0.56; = 0.52, n = 46) primary septum, reddish-brown, thick-walled, verrucose, with 2–5 μm thick sheath. Asexual state: unknown.

Material examined – JAPAN, Fukushima, Minamiaizu, Ose pond, on dead twigs of Sasa sp. (Poaceae), 30 Aug. 2003, N. Asama, (KT 1466 = HHUF 28229), living culture CBS 120248 = JCM 13543 = MAFF 239276; Hokkaido, Isl. Rishiri, Afutoromanai river, on dead twigs of Sasa kurilensis, 29 July 2007, K. Tanaka & G. Sato, (KT 2313 = HHUF 30016), living culture = NBRC 106240.

Fig. 1 Neokalmusia brevispora (KT 1466). a–b Ascomata on host surface. c–d Vertical section through ascomata. e Section through peridium. f Pseudoparaphyses. g–h Asci. i Ocular chamber. j Germinating ascospore. k–o Ascospores. Scale bars: a–b = 1 mm, c–d = 100 µm, e–o = 10 µm.

Notes – A new genus Neokalmusia is established to accommodate two bambusicolous taxa, N. brevispora and N. scabrispora. These species have been previously placed in Kalmusia(Tanaka et al. 2005; Zhang et al. 2009), but subsequent molecular studies (Hyde et al. 2013) as well as in the present study (Fig. 1), do not support this placement. Morphological studies of Kalmusia based on the holotype of K. ebuli (type of this genus) indicated that the genus is characterized by solitary sphaeroid ascomata, a peridium of small pseudoparenchymatous cells, clavate basal asci with very long pedicels, very thin pseudoparaphyses and distoseptate, smooth-walled ascospores (Zhang et al. 2012, this study). The two Neokalmusia species on bamboo have subglobose to oblong ascomata including several perithecia in a row, clypeus-like structure composed of thin-walled cells and verrucose ascospores.