Neopalmiascoma macadamiae X. Zhang, K. D. Hyde, Tibpromma & Karunarathna 2024, sp. nov.
Creators: name: Zhang, Xian
name: Karunarathna, Samantha C.
name: Tibpromma, Saowaluck
name: Du, Tian-Ye
name: Elgorban, Abdallah M.
name: Lumyong, Saisamorn
name: Dai, Dong-Qin
name: Hyde, Kevin D.
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Fungi
Ascomycota
Dothideomycetes
Pleosporales
Bambusicolaceae
Neopalmiascoma
Neopalmiascoma macadamiae

description: Neopalmiascoma macadamiae X. Zhang, K.D. Hyde, Tibpromma & Karunarathna, sp. nov.
Index Fungorum IF901496, Facesoffungi FoF 15279; FIGURE 2.
Etymology: Named after the host genus, Macadamia.
Holotype: ZHKU 23-0096
Saprobic on a dead branch of Macadamia integrifolia. Sexual morph: Ascomata 70–190 μm × 100–160 μm (x̄ = 102 × 128 μm, n = 10), solitary, semi-immersed, dark brown to black, unilocular, subglobose to ampulliform, ostiolate, papillate. Ostioles centric or eccentric, periphysate, carbonaceous. Peridium 10–25 μm wide (x̄ = 19.5 μm, n = 20), thick-walled, outer cells merging with the host epidermal cells, tending to be smaller, brown to dark brown cells of textura angularis, thin-walled towards the outside, and inner cells composed thick-walled, light-brown of textura angularis cells. Hamathecium comprising 1–5 μm wide (x̄ = 2.3 μm, n = 30), branched, dense, cellular pseudoparaphyses, longer than asci. Asci 40–90 × 7–15 μm (x̄ = 54 × 11 μm, n = 30), 6–8-spored, cylindric-clavate, fissitunicate, bitunicate, pedicellate, slightly curved, rounded at the apex. Ascospores 8–13 × 3–6 μm (x̄ = 11.1 × 5 μm, n = 40), overlapping, didymosporous, fusiform with obtuse ends, broadly fusiform to ellipsoid, constricted at the septum, 1-septate, hyaline to yellowish-brown when immature, brown to dark-brown when mature, slightly wider upper cell, tapering towards the slightly rounded ends, straight or slightly curved, with 2–3 guttules, with mucilaginous sheath, echinulate, rough-walled. Asexual morph: Undetermined.
Culture characteristics: Ascospores germinated on PDA within 24 h. Above: pure colonies on PDA after one month is flossy, irregular, umbonate, undulate edge, white to pale brown in above, forming tufts on surface, wrinkled. Reverse: white to grey from the edge to the center, accompanied by cracks in the middle, white to grey at the margin, a brown ring in the middle to separate it.
Material examined: China, Yunnan Province, Baoshan City, 24°55′17″ N, 98°50′37″ E, 958 m elevation, on a dead branch of Macadamia integrifolia, 29 July 2022, X. Zhang, MBL72 (holotype, ZHKU 23-0096); ex-type culture, ZHKUCC 23-0746, ZHKUCC 23-0747.
Notes: The NCBI BLASTn search of our new collection matched with Palmiascoma gregariascomum (MFLUCC 11-0175) by giving 96.78% percent identity in ITS sequences; the LSU sequences matched with Bambusicola loculata (MFLUCC 13-0856) with 98.75% similarity; the TEF1-α matched with Palmiascoma qujingense (KUMCC 19-0201) with 91.75% similarity; the RPB2 matched with Bambusicola pustulata (MFLUCC 15-0190) with 78.54% similarity; and the SSU sequences of our new collection matched with Palmiascoma qujingense (KUMCC 19-0201) with 99.30% similarity.
Neopalmiascoma macadamiae (ZHKU 23-0096) can be distinguished from Palmiascoma gregariascomum (MFLUCC 11-0175) and P. qujingense (KUMCC 19-0201) by having solitary, semi-immersed ascomata, 6–8-spored asci, constricted at the septum ascospores with echinulate, rough-walled, the culture on PDA is flossy, irregular, umbonate, undulate edge, white to pale brown in above, wrinkled, reverse accompanied by cracks in the middle, white to grey at the margin; P. gregariascomum has gregarious, scattered to clustered, semi-immersed to erumpent ascomata, 8-spored and well-developed ocular chamber asci, ascospores not constricted at the septa, the culture on PDA is greenish-grey to grey, slightly radiating, circular, reverse brown to dark brown at the margin (Liu et al. 2015); while P. qujingense has clustered or scattered and glabrous ascomata, 8-spored asci, and ascospores lacking a mucilaginous sheath, the culture on PDA is white to creamy, reverse creamy (Monkai et al. 2021). Therefore, based on morphology and molecular data, we introduce the new genus Neopalmiascoma, to accommodate N. macadamiae.
description: Published as part of Zhang, Xian, Karunarathna, Samantha C., Tibpromma, Saowaluck, Du, Tian-Ye, Elgorban, Abdallah M., Lumyong, Saisamorn, Dai, Dong-Qin & Hyde, Kevin D., 2024, Morphology and phylogenetic analyses reveal Neopalmiascoma gen. nov. (Bambusicolaceae, Pleosporales) on Macadamia integrifolia in Yunnan Province, China, pp. 230-240 in Phytotaxa 633 (3) on pages 235-236, DOI: 10.11646/phytotaxa.633.3.3, http://zenodo.org/record/13879100