Neobrevicollum biancaeae H.Z. Du, Y.H. Lu & Jian K. Liu, 2024

Lu, Yu-Hang, Zhang, Sheng-Nan, Du, Hong-Zhi, Cheewangkoon, Ratchadawan & Liu, Jian-Kui, 2024, Additions to Crassiparies and Neobrevicollum (Neohendersoniaceae, Pleosporales) associated with woody hosts in Southwest China, Phytotaxa 636 (2), pp. 126-138 : 131-132

Neobrevicollum biancaeae H.Z. Du, Y.H. Lu & Jian K. Liu , sp. nov., Fig. 2 MycoBank: MB 851140

Etymology:— The epithet ‘ biancaeae ’ refers to the host genus Biancaea on which the fungus was collected.

Holotype: — HKAS 130507

Saprobic on dead branches of Biancaea sappan . Sexual morph: Ascomata 109–145 µm high, 125–200 µm diam (x = 122 × 170 µm, n = 10), immersed, scattered, uniloculate, globose or subglobose, glabrous, dark brown to black, thin-walled, and white interior, without ostiole. Peridium 9–14 µm wide, thin, composed of several layers of brown cells of textura angularis. Hamathecium 1.7–2.5 µm wide (x = 2 µm), numerous, filamentous, cellular pseudoparaphyses, with indistinct septa. Asci 68–140 × 16–25 µm (x = 112 × 20 µm, n = 30), 8-spored, hyaline, bitunicate, fissitunicate, cylindrical to clavate with a short pedicel, apically rounded, with a small ocular chamber. Ascospores 30–35 × 9–13 µm (x = 32 × 11 µm, n = 30), 1–2-seriate, overlapping in the ascus, hyaline to pale yellowish-brown, broadly fusiform, 1-septate, constricted at the septa, obtuse at both ends, smooth-walled, surrounded by a mucilaginous sheath, guttulate. Asexual morph: Undetermined.

Culture characteristics: —Ascospores germinated within 24 hours on PDA. Colonies on PDA reaching about 34 mm after one month incubated at 25 °C, irregular, with undulate edge, dark brown to brown at the surface with white margin and brown from the centre of the colony in reverse with white margin.

Material examined: — CHINA, Yunnan Province, Xishuangbanna Dai autonomous prefecture, Xishuangbanna tropical botanical garden Chinese Academy of Sciences. 101°15′6′′E, 21°55′51′′N, 502 m elevation, on dead branches of medicinal plant Biancaea sappan (L.) Tod.9 ( Fabaceae ), 9 November 2022, H.Z. Du, S578A (HKAS 130507, holotype); ex-holotype living culture CGMCC 3.25420); ibid., HUEST 23.0142, isotype, ex-isotype living culture UESTCC 23.0142.

Notes:— Neobrevicollum biancaeae morphologically fits into the generic concept of Neobrevicollum by having immersed, uniloculate and globose ascomata, numerous and hyaline pseudoparaphyses, bitunicate, cylindrical to obclavate asci with a cylindrical pedicel, hyaline, overlapping, fusiform, 1-septate ascospores with a mucilaginous sheath ( Li et al. 2023). However, N. biancaeae differs from N. oleae in having thin-walled ascomata without ostiolate, smaller ascomata (125–200 × 109–145 μm vs. 230–270 × 200–230 μm), and asci (68–140 × 16–25 µm vs. 105–135 × 18–23 μm) ( Li et al. 2023). The results of phylogenetic analysis also indicated that N. biancaeae and N. oleae are phylogenetically distinct species and N. biancaeae (CGMCC 3.25420 and UESTCC 23.0142) formed separate clade with statistical support (100% ML/1.00 BYPP) ( Fig. 1 ). Additionally, N. biancaeae can be distinguished from N. oleae based on ITS, LSU, and TEF1-α base pair differences; ITS = 25/433 (5.77%), LSU = 8/852 (0.94%), and TEF1-α = 31/909 (3.41%).

Figures

FIGURE 1. Phylogenetic tree from ML analysis based on the combined ITS, SSU, LSU, RPB2, and TEF1-α sequences data. Bootstrap values for ML and MP ≥ 75% are placed above the branches. Branches with Bayesian posterior probabilities (BYPP) ≥ 0.95 are in bold. The tree is rooted to Cyclothyriella rubronotata (CBS 141486 and CBS 419.85). The ex-type strains were indicated in bold, and newly generated sequences were indicated in red.

FIGURE 2. Neobrevicollum biancaeae (HKAS 130507, holotype) a Substrate. b Ascomata on host surface. c Vertical section of ascomata. d–i Asci. j Hamathecium. k Peridium. l–o Ascospores. p Germinating ascospore. q Ascospore stained with India ink showing the mucilaginous sheath. Scale bars: c = 100 µm, d–i = 20 µm, j, k = 30 µm, l–q = 20 µm.