Fissuroma bambucicola Y. Feng, S.N. Zhang & Z.Y. Liu, 2022

Feng, Yao, Zhang, Sheng-Nan, Chen, Ya-Ya & Liu, Zuo-Yi, 2022, Fissuroma bambucicola sp. nov. (Aigialaceae, Pleosporales) from Bamboo in Guizhou, China, Phytotaxa 543 (1), pp. 64-72 : 68

Fissuroma bambucicola Y. Feng, S.N. Zhang & Z.Y. Liu , sp. nov.

Index Fungorum number: IF559418; Facesoffungi number: FoF 10587;

FIGURE 2 .

Holotype:— HKAS 122239 .

Etymology:—The epithet refers to the bamboo substrate on which the new fungus was collected.

Saprobic on the dead stem of bamboo, forming a layer of black particles visible to the naked eye on the host surface. Sexual morph: Ascomata 282–344 μm high, 568–607 μm wide (x = 304 × 587 μm, n = 10), erumpent to superficial, solitary to gregarious, black, hemispherical, base flattened, with a slit on its surface, slit-like ostioles with periphyses, unilocular. Peridium is uneven thickness, thin at the base and thicker on both sides towards the tip, consisting of several layers of dark brown to black pseudoparenchyma. Pseudoparaphyses hyaline, trabeculate, anastomosing, embedded in a gelatinous matrix. Asci 170–202 × 21–27 μm (x = 189 × 24 μm, n = 20), 8-spored, bitunicate, fissitunicate, cylindric-clavate or obclavate, wide in the middle, tapering to the edges, apically obtusely rounded with a small ocular chamber, base with a short pedicel. Ascospores 50–64 × 8–11 μm (x = 57 × 10 μm, n = 30), overlapping 1–2 seriate, fusiform, hyaline, smooth-walled, tapering to pointed apices, 1-septate (rarely 3-septate), slightly constricted at the septum, guttulate, surrounded by a thin mucilaginous sheath. Asexual morph: Undetermined.

Culture characteristics:—Ascospores germinated in WA medium within 24 h, and the germ tube extended out from one end of the ascospore. Colonies on PDA reaching 1 cm after seven days incubated at 25˚C. Colonies have entire, rounded, smooth, leathery edges with grayish-white upper layers and gray lower layers. Reverse grayish brown with grayish-white edges.

Material examined:— CHINA, Guizhou, Anshun city. On decaying bamboo stems, 1 May 2019, Yao Feng, AS 4 ( HKAS 122239 , holotype ; GZAAS 21−0185 , isotype) ; ex-type living culture CGMCC3.20678 = GZCC 21−0699 . Ibid., Xingyi city. On decaying bamboo stems, 7 August 2019, Yao Feng, XY 19-7 ( GZAAS 21−0186 , paratype); living culture GZCC 21−0700 .

Notes:— Fissuroma bambucicola morphologically lines well with Fissuroma by having carbonaceous ascomata with slit-like ostioles and fusiform, hyaline ascospores. Multi-gene phylogenetic analyses showed that it has a close relationship with F. aggregatum (KT 984). However, Fissuroma aggregatum (= Astrosphaeriella aggregata ≡ Melanopsamma aggregate ) was represented by more than one specimen, two of which have available molecular data (KT 984 = HHUF 28233, KT 767 = HHUF 28232) ( Tanaka & Harada 2005; Tanaka et al. 2009; Liu et al. 2011; Phookamsak et al. 2015). In this study, F. aggregatum (KT 767) formed an independent lineage within Fissuroma , while F. aggregatum (KT 984) formed a sister branch with F. bambucicola . A comparison of the 936 nucleotides across the TEF gene region of F. bambucicola and F. aggregatum (KT 984) showed 36 bp (900/936 bp) differences. Morphologically, Fissuroma bambucicola is easily distinguished from F. aggregatum and the three species in Fissuroma for which no molecular data are available [ F. fissuristoma (J. Fröhl., K.D. Hyde & Aptroot) Phookamsak & K.D. Hyde , F. kavachabeejae M. Niranjan & V.V. Sarma , and F. microsporum M. Niranjan & V.V. Sarma ] ( TABLE 2 .), because of its larger asci and ascospores. In addition, the two ends of F. bambucicola ‘s mucilaginous sheath do not protrude, so the distinct morphology of F. bambucicola provides strong evidence to be a new species in Fissuroma .

Figures

FIGURE 2. Fissuroma bambucicola (HKAS 122239, holotype) (A, B) Appearance of ascomata on host. (C) Vertical section of ascomata. (D) Periphyses. (E) Germinating ascospore. (F) Pseudoparaphyses. (G, H) Culture (G above, H reverse). (I−K) Asci. (L−N) Ascospores. Scale bars: C = 200 μm. E = 30 μm. F = 10 μm. I−K = 50 μm. L−N = 20 μm.