Nigrograna camelliae Y. H. Lu, H. Z. Du & Jian K. Liu 2024, sp. nov.
Creators: name: Du, Hong-Zhi
name: Lu, Yu-Hang
name: Cheewangkoon, Ratchadawan
name: Liu, Jian-Kui
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Fungi
Ascomycota
Dothideomycetes
Pleosporales
Nigrogranaceae
Nigrograna
Nigrograna camelliae

description: Nigrograna camelliae Y. H. Lu, H. Z. Du & Jian K. Liu sp. nov.
Fig. 5
Etymology.
The epithet ‘ camelliae ’ refers to the host genus Camelliae from which the fungus was originally isolated.
Holotype.
HKAS 131310
Description.
Saprobic on dead branches of Camellia sinensis (Theaceae). Sexual morph: Ascomata 137–270 μm wide, 208–324 μm high (x ̅ = 212 × 265 μm, n = 20), solitary, scattered, immersed, black spots on the host substrate, globose to subglobose, sometimes obpyriform, ostiolate, hairs of ascomata 2–3 μm wide, slightly brown, septate. Ostioles 65–138 μm long, 32–60 μm wide (x ̅ = 100 × 45 μm, n = 20) mostly central, some eccentric, with a crest-like apex. Peridium 19–30 μm (x ̅ = 23 μm, n = 20) wide, composed of 2–3 layers, comprising reddish brown to dark brown pigmented cells. Hamathecium 2–3 μm (x ̅ = 2.5 μm, n = 20) wide, composed of numerous, filiform, hyaline, aseptate or separate, filamentous, smooth-walled pseudoparaphyses. Asci 70–108 × 9–11 μm (x ̅ = 80 × 10 μm, n = 30), 8 - spored, bitunicate, fissitunicate, clavate to cylindric-clavate, short stalked, some with a swollen base, apically rounded, with a small ocular chamber. Ascospores 13–16 × 4–6 μm (x ̅ = 15 × 5 μm, n = 50), overlapping uni- to bi-seriately arranged, fusoid to ellipsoid, tapering towards the blunt ends, or blunt at both ends, straight or slightly curved, 1 - septate, constricted, with obviously guttulate, hyaline to slightly brown when immature, pale brown to brown when mature, without appendages. Asexual morph: Undetermined.
Culture characteristics.
Ascospores germinated on PDA within 24 h, and germ tubes produced from basal cell. Colonies growing on PDA reached 35–36 mm in diameter after three weeks at 25 ° C in dark, white in the whole colony and slightly bright yellow in the center from above, circular, edge entire, margin well-defined; in reverse, yellowish brown in the center, slightly brown at the margin and presented an outer ring, no pigmentation on PDA.
Material examined.
China • Sichuan Province, Yaan City, Mingshan County, Mengding Mountain. 30°4'32"N, 103°2'23"E, elevation 1,200 m, on dead branches of medicinal plant Camellia sinensis (L.) O. Ktze. (Theaceae), 16 July 2023, Y. H. Lu & X. D. Liang, MD 03 A (HKAS 131310, holotype; HUEST 23.0197, isotype); ex-holotype living culture CGMCC 3.25625; ex-isotype living culture UESTCC 23.0197.
Notes.
Nigrograna camelliae is phylogenetically close to N. coffeae and represents as a distinct lineage (Fig. 1). Additionally, the nucleotide base pair comparison between N. camelliae (ex-type strain, CGMCC 3.25625) and N. coffeae (ex-type strain, ZHKUCC 22-0210) revealed 15 / 514 bp (2.9 %, 1 gap) of ITS, 11 / 698 bp (1.6 %, without gaps) of LSU, 74 / 739 bp (10.0 % without gaps) of rpb 2 and 28 / 914 bp (3.1 %, without gaps) of tef 1 - α differences. Furthermore, N. camelliae morphologically resembles N. coffeae in having immersed ascomata, clavate and short pedicellate asci, pale brown to brown and septate ascospores with obviously guttulate (Lu et al. 2022). However, N. camelliae differs from N. coffeae in having ascomata with hairs and ostioles, solitary or scattered in the substrate. Additionally, they can be distinguished in having larger ascomata (208–324 × 137–270 µm vs. 140–200 × 90–140 µm) and asci (70–108 × 9–11 µm vs. 50–70 × 7–11 µm). Therefore, N. camelliae is introduced as a new species with the justification of phylogenetic and morphological evidence.
description: Published as part of Du, Hong-Zhi, Lu, Yu-Hang, Cheewangkoon, Ratchadawan & Liu, Jian-Kui, 2024, Morpho-phylogenetic evidence reveals novel species and new records of Nigrograna (Nigrogranaceae) associated with medicinal plants in Southwestern China, pp. 1-33 in MycoKeys 110 on pages 1-33, DOI: 10.3897/mycokeys.110.132628