Morpho-phylogenetic evidence reveals new species in Rhytismataceae (Rhytismatales, Leotiomycetes, Ascomycota) from Guizhou Province, China Author Zhang, Jin-Feng https://orcid.org/0000-0003-0765-2485 Institute of Tea Research, Guizhou Academy of Agricultural Sciences, Guiyang 550006, China & Guizhou Key Laboratory of Agriculture Biotechnology, Guizhou Academy of Agricultural Sciences, Guiyang 550006, China & Center of Excellence in Fungal Research and School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand Author Liu, Jian-Kui https://orcid.org/0000-0002-9232-228X Guizhou Key Laboratory of Agriculture Biotechnology, Guizhou Academy of Agricultural Sciences, Guiyang 550006, China & School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 611731, China Author Hyde, Kevin D. Center of Excellence in Fungal Research and School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand & Innovative Institute of Plant Health, Zhongkai University of Agriculture and Engineering, Haizhu District, Guangzhou 510225, China & Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China Author Ekanayaka, Anusha H. Center of Excellence in Fungal Research and School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand & Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China Author Liu, Zuo-Yi Guizhou Key Laboratory of Agriculture Biotechnology, Guizhou Academy of Agricultural Sciences, Guiyang 550006, China gzliuzuoyi@163.com text MycoKeys 2020 2020-12-31 76 81 106 http://dx.doi.org/10.3897/mycokeys.76.58465 journal article http://dx.doi.org/10.3897/mycokeys.76.58465 1314-4049-76-81 521CFDA6D9F95A25AB0EF6B1F5742E80 Terriera sigmoideospora J.F. Zhang & K.D. Hyde sp. nov. Figure 5 Holotype. MFLU 18-2297. Etymology. Refers to its sigmoidal ascospores. Description. Apothecia developing on fallen leaves, scattered, dark brown to black, matt, elliptical, sometimes 3-lobed or triangular, straight or slightly curved, ends rounded to subacute, strongly raising the surface of the substrate at maturity, opening by a single longitudinal split that extends almost the whole length of the apothecium (Fig. 5a, b ). Immature apothecia appearing as a single dark brown protrusion, circular to slightly elongated. In median vertical section (Fig. 5d ), apothecia 185-220 μm deep. Covering stroma (Fig. 5c ) 20-25 μm thick near the centre of the apothecium, consisting of an outer layer of host cuticle, remains of epidermal and hypodermal cells filled with thick-walled, angular fungal cells and an inner layer of textura angularis to textura globulosa with 4-7 μm diam., dark brown, thick-walled cells, slightly thinner towards the edges, extending to the basal stroma, but conspicuously thicker towards the apothecial opening, with a 15-27 μm thick extension comprising highly melanised tissue with no obvious cellular structure. Excipulum moderately developed, closely adhering to the covering stroma and the extension, arising from the marginal paraphyses, becoming thinner towards the base. Basal stroma concave, 12-15 μm thick, composed of dark brown, thick-walled, angular cells. A triangular space between the covering stroma and basal stroma is composed of thin-walled, colourless cells that are vertically arranged in rows. Subhymenium 6-9 μm thick, flat, consisting of hyaline cells of textura intricata . Paraphyses filiform, hyaline, septate, gradually or suddenly swollen to 2.5 μm near the apex, covered by a thin gelatinous sheath, forming a 4-8 μm thick epithecium. Asci (93.5-)102-121 x 5-6 μm ( x ¯ = 108.5 x 5.5 µm , n = 20), 8-spored, unitunicate, cylindrical, apex tapering to round, thin-walled, J-, without circumapical thickening. Ascospores 79-95 x 1.5-2 μm ( x ¯ = 89.5 x 1.9 µm , n = 30), fascicle, filiform, sigmoid, tapering slightly towards the ends, hyaline, aseptate, guttulate, gelatinous sheath not observed. Asexual morph : Not observed. Figure 5. Terriera sigmoideospora a, b apothecia observed under the dissecting microscope c section of covering stroma d median vertical section through an apothecium e immature ascus f paraphyses and asci in various states of maturity g, h ascospores. Note: c-h mounted in water. Scale bar: 1 mm ( a ), 500 µm ( b ), 100 µm ( c ), 20 µm ( d-h ). Material examined. CHINA, Guizhou Province, Guiyang, dead leaves of unidentified host, 5 October 2016, J.F. Zhang, GZ-28 (MFLU 18-2297, holotype ); ibid . (GZAAS 19-1729, isotype ). Notes. In the present phylogenetic analysis (Fig. 1 ), Terriera sigmoideospora is placed within Terriera and is related to T. houjiazhuangensis C.L. Hou & S.R. Hou by strong statistical support (MPBP 99% and BYPP 1.00). Terriera sigmoideospora shares similar-sized asci with T. houjiazhuangensis (102-121 x 5-6 μm vs. 103-128 x 4-6 μm ), but has larger ascospores (79-95 x 1.5-2 μm vs. 73-82 x 0.6-0.9 μm ) ( Cai et al. 2020 ). Besides, the ascospores of T. houjiazhuangensis are enveloped by an inconspicuous gelatinous sheath, while this is not observed in T. sigmoideospora . In addition, the comparison of the ITS gene region between these two taxa has been processed and showed that there are 19/815 (2.3%) bp differences. Terriera pandanicola is sister to the above two taxa; however, it is significantly distinguished from T. sigmoideospora as its obviously smaller asci (50-66 x 4-5 μm vs. 102-121 x 5-6 μm ) and ascospores (55-78 x 1-2 μm vs. 79-95 x 1.5-2 μm ) ( Tibpromma et al. 2018 ).