Lindgomyces okinawaensis Tak. Takah. & Kaz. Tanaka, sp. nov.
MycoBank number: MB 815296; Facesoffungi number: FoF 02022, Fig. 1
Etymology: In reference to the locality, Okinawa where the new species was collected.
Holotype: HHUF 30498

Saprobic on submerged dead wood. Sexual morph Ascomata 260 – 290 μm high, 310 – 340 μm diam., globose to subglobose, black, scattered to grouped, immersed to erumpent. Neck 50 – 60 μm long, 50 – 75 μm wide, short papillate, central. Peridium 35 – 41 μm thick, composed of an inner layer of polygonal to subglobose, hyaline to pale brown, thin-walled, 8 – 12 × 6 – 7.5 μm cells, and an outer layer of brown – walled cells. Hamathecium comprising numerous, 1.5 – 3 μm wide, anastomosed, branched, cellular pseudoparaphyses. Asci 134.5 – 183 (–208) × (18.5–) 23 – 31 (–40.5) μm (x̄ = 160.9 × 26.5 μm, n = 12), 8 – spored, fissitunicate, clavate, rounded at the apex,with an apical chamber. Ascospores (38–) 40 – 48 (–51) × (10–) 12 – 19 μm (x̄ = 44.9 × 14.9 μm, n = 50), L/W 2.2–4.3 (x̄ = 3.1, n = 50), overlapping biseriate to triseriate, hyaline, pale brown with age, clavate with acute ends, straight or slightly curved, with the primary septum almost submedian 0.46 – 0.58 (x̄ = 0.52, n = 50), filled with small lipid roplets, slightly constricted at the primary septum, with a broad upper cell, smooth-walled, becoming 3-septate with age. Asexual morph Undetermined.

Material examined: JAPAN, Okinawa, Kunigami, Aha, Tanagakumui, small river, on submerged dead twigs of woody plant, 19 May 2015, collector K. Tanaka et al., KT 3531 (HHUF 30498, holotype); ex-type living culture, MAFF 245410.

Notes: Lindgomyces okinawaensis has relatively wide ascospores. The morphological features of ascospores are similar to those of L. cinctosporus (Hirayama et al. 2010). However, the ascospores of L. okinawaensis do not have an entire gelatinous sheath. The identities of ribosomal ITS sequences between L. okinawaensis and L. cinctosporus were low [GenBank JF419905; Identities = 408/432 (94.4 %), Gaps=2/432 (0.5 %)].

Fig. 1 Lindgomyces okinawaensis a, b Appearance of ascomata on host surface c, d Ascomata formed in culture e Ascoma in longitudinal section f Peridium in longitudinal section g Pseudoparaphyses h – j Asci k – n Ascospores a, b, e, g, i from HHUF 30498 (holotype); c, d, f, h, j – n from MAFF 245410 (ex-holotype). Scale bars: a, c = 1 mm, b, d = 200 μm, e = 50 μm, f – n = 20 μm.