Arecophila australis Q.R. Li, J.C. Kang & K.D. Hyde, 2022

Li, Qi Rui, Zhang, Xu, Lin, Yan, Samarakoon, Milan C., Hyde, Kevin David, Shen, Xiang Chun, Liao, Wan Qing, Karunarathna, Anuruddha, Long, Si Han, Kang, Ying Qian & Kang, Ji Chuan, 2022, Morpho-molecular characterisation of Arecophila, with A. australis and A. clypeata sp. nov. and A. miscanthi comb. nov., MycoKeys 88, pp. 123-149 : 123

Arecophila australis Q.R. Li, J.C. Kang & K.D. Hyde sp. nov.

Fig. 2

Diagnosis.

Arecophila australis differs from similar species by its dimension of ascospores (22.5-29 × 8-11 µm) covered by striations and ascomata with a disc area surrounding the ostioles.

Holotype. China, Guizhou Province, Guiyang City, Forest Park of Guiyang (26°32'55"N, 106°45'25"E), on dead culm of Phragmites australis (Cav.) Steud., 15 March 2014, Q.R. Li, GZ58 (GZUH0112, holotype, ex-type: GZUCC0112; GACP QR0152, isotype).

Additional sequences.

ACT: MT741737

Etymology.

In reference to the host, Phragmites australis (Cav.) Steud. australis

Description.

Saprobic on dead culm of gramineous host. Sexual morph: Ascomata 420-560 × 290-380 µm (x̄ = 495 × 325 µm, n = 10), immersed under a clypeus, solitary, slightly raised, blackened, dome-shaped areas, scattered or gregarious, globose to subglobose, with a central, erumpent, cone-shaped papilla in vertical section. Clypeus Clypeus black, comprising host cells and intracellular brown hyphae. Ostioles papillate, black. Peridium 15-25 µm (x̄ = 21 µm, n = 15) wide, comprising several layers, outer layer brown, thick-walled angular cells, inner layer hyaline. Paraphyses 3.3-5 μm (x̄ = 3.5 µm, n = 15) wide, hyaline, unbranched, septate. Asci 140-230 × 15.5-24 µm (x̄ = 183.5 × 19 µm, n = 30), 8-spored, unitunicate, long-cylindrical, short-pedicellate, apically rounded, with a 4-5 × 2.5-3 μm (x̄ = 4.5 × 2.7 μm, n = 20), trapezoidal, J+, apical ring. Ascospores 22.5-29 × 8-11 µm (x̄ = 25.5 × 9 µm, n = 30), overlapping uniseriate, 2-celled, light brown to brown, equilateral ellipsoidal, constricted at the septum, longitudinal with sulcate striations, along the entire spore length, surrounded by a mucilaginous sheath, lacking germ slits and appendages. Asexual morph: undetermined.

Culture characteristics.

Colonies on PDA, reached 3 cm diam. after one week at 25 °C, white, cottony, flat, low, dense, with slightly wavy margin.

Known distribution.

China

Additional material examined.

China, Guizhou Province, Guiyang City, Leigongshan National Nature Reserve (26°21'39"N, 108°9'59"E), on dead culm of an unidentified gramineous plant, 13 June 2015, Q.R. Li, GY67 (GACP QR0124, GZUH 0136; living cultures, GZUCC0124) .

Notes.

Arecophila australis resembles A. serrulata (Ellis & Martin) K.D. Hyde and A. calamicola K.D. Hyde ( Hyde 1996). However, A. serrulata has white ring surrounding ostioles of ascomata, narrower ascospores (17-26 × 7-9.5 µm vs. 22.5-29 × 8-11 µm), smaller asci and apical ring (3.2 × 2.4 µm vs. 4.5 × 2.7 μm) compared to A. australis ( Hyde 1996). Arecophila calamicola differs from A. australis in lacking clypeus, ascospores covered by verrucose ornamentation and surrounding by a mucilaginous sheath attached at the poles. Molecular phylogeny, based on combined ITS, LSU, rpb 2 and β-tubulin sequences, shows that A. australis clusters as a distinctive clade in Arecophila (Clade 1). Based on its distinct morphology and phylogeny, A. australis is introduced as a new species. Here, we need to explain the name of A. serrulata . Although Index Fungorum (02/07/2022) shows that the current name of A. serrulata is Roussoella serrulata (Ellis & G. Martin) K.D. Hyde & Aptroot, we have not found relevant literature. Hyde (1996) renamed Didymosphaeria serrulota Eltis & G. Martin and Roussoella serrulata as synonyms of A. serrulata (Ellis & G. Martin) K.D. Hyde. Arecophila serrulata was erected with the unitunicate asci with a blue-staining ring ( Hyde 1996) which is clearly inconsistent with the morphological features of Roussoella Sacc. Therefore, we still compare with the original description of A. serrulata in this article.

Figures

Figure 2. Arecophila australis (holotype) A material B ascoma on the surface of host C section of ascoma D peridium E paraphyses F, G ascus apex with a J +, apical ring (stained in Melzer's reagent) H-K asci with ascospores L-O ascospores surrounded by a wide mucilaginous sheath (O stained in India ink). Scale bars: 300 μm (B); 50 μm (C); 5 μm (D-O).