Leptospora macarangae Tennakoon, C.H. Kuo & K.D.Hyde.
Index Fungorum number: IF555317; Facesoffungi number: FoF 09323, Fig. 1
Etymology: Name reflects the host, Macaranga tanarius.
Holotype: MFLU 18-0075
Saprobic on dead leaf petiole of Macaranga tanarius.Sexual morph: Ascomata 200–250 × 100–120 μm ( ̄x=226 × 110 μm, n = 20), solitary or aggregated, immersed to semi-immersed, erumpent, globose to subglobose, coriaceous, ostiolate. Ostiole central, papillate, cylindrical, truncate at the apex, dark brown to light brown, ostiloar canal filled with periphyses, and produces a reddish-purple discoloration in host tissue around ostiole. Peridium 12–15 μm wide, thin-walled, of equal thickness, composed of several layers of small, flattened, brown to dark brown pseudoparenchymatous cells, cells towards the inside hyaline, arranged in a textura angularis, fusing and indistinguishable from the host tissues. Hamathecium comprising numerous, 1.5–3 μm wide, filamentous, cellular pseudoparaphyses, anastomosing above and between the asci. Asci 65–78 × 8–9 μm ( ̄x = 71 × 8.5 μm, n = 20), 8-spored, bitunicate, cylindrical to cylindrical-clavate, with short pedicel, apically rounded to truncate with a minute ocular chamber. Ascospores 63–75 × 3–3.8 μm ( ̄x = 68.5 × 3.5 μm, n = 30), fasciculate, tritomultiseriate, scolecosporous, filiform, tapering towards the ends, minute guttules in each cell, hyaline when young, become pale brown at maturation, normally 13-septate, not constricted at the septa, minute guttule in each cell, straight or slightly curved, with polar appendages. Asexual morph: Undetermined.

Culture characteristics: Colonies on PDA, 30–40 mm diam. after 3 weeks, colonies from above: medium dense, irregular, flat, slightly raised, surface smooth, irregular, undulate or wavy margin, light brown at the margin, cream to white in the centre; reverse: light brown at the margin, dark brown in the centre.

Material examined: Taiwan, Chiayi, Ali Shan Mountain, Fanlu Township area, Dahu forest, dead leaf petiole of Macaranga tanarius (Euphorbiaceae), 05 June 2019, D. S. Tennakoon, M009A (MFLU 18-0075, holotype); ex-type living culture, MFLUCC 18-0553, ibid., 10 June 2019, M009B (NCYU 19-0345, paratype); ex-paratype living culture, NCYUCC 19-0228.

GenBank numbers: MFLUCC 18-0553: LSU: MW063232; SSU: MW079354; ITS: MW063171. NCYUCC 19-0228: LSU: MW063233; SSU: MW079355; ITS: MW063172.

Notes: The morphology of our collection tallies with that described for Leptospora in having large, flask-shaped ascomata with long cylindrical asci and thin, filiform, multiseptate ascospores (Hyde et al. 2016; Zhang et al. 2019a; Mapook et al. 2020). In the phylogenetic tree, Leptospora macarangae clusters with L. hydei (GZCC 19-0004) with 100% ML, 1.00 BYPP statistical support (Fig. 2). Leptospora macarangae can be distinguished from L. hydei in having smaller asci (65–78 × 8–9 μm) and ascospores (63–75 × 3–3.8 μm) with polar appendages, whereas L. hydei has larger asci (147–165 × 13–17 μm) and ascospores (124–138× 4–4.8 μm), lacking appendages (Zhang et al. 2019a). Other morphological differences are listed in Table 1.

Fig. 1 Leptospora macarangae (MFLU 18-0075, holotype): a Dead leaf of Macaranga tanarius. b Appearance of ascomata on host. c Section
of an ascoma. d Section of peridium. e Ostiolar canal filled with periphyses. f Pseudoparaphyses. g–i Asci. j–l Ascospores. m, n Club-shaped
appendages. o A germinating ascospore. p Colonies from above (on PDA). q Colonies from below (on PDA). Scale bars: c = 50 μm, d = 10 μm,
e = 20 μm, f–i = 20 μm, j–l = 15 μm, m, n = 3 μm, o = 15 μm

Fig. 2 The best scoring RAxML tree with a final likelihood value of – 6194.954042 for combined dataset of LSU, SSU, ITS and TEF1-α sequence data. The topology and clade stability of the combined gene analyses was compared to the single gene analyses. The tree is rooted with Phaeosphaeria musae (MFLUCC 17-2648) and P. oryzae (CBS 110110). The matrix had 194 distinct alignment patterns with 13.63% undetermined characters and gaps. Estimated base frequencies were as follows; A = 0.248447, C = 0.229902, G = 0.264077, T = 0.257574; substitution rates AC = 0.993589, AG = 2.533063, AT = 3.978019, CG = 0.387735,CT = 10.624462, GT = 1.000000; gamma distribution shape parameter α = 2.632698. Ex-type strains are in bold and newly generated sequences are in red. Bootstrap support values for ML equal to or greater than 60% and BYPP equal to or greater than 0.90 are given above the nodes.

Table 1. Synopsis of Leptospora species with similar morphology features discussed in this study