Acrogenospora guangxiensis Y.X. Shu & W. Dong, sp. nov.
Index Fungorum Number: IF 903081; MycoBank Number: MB 903081; Facesoffungi Number: FoF 17021;
Etymology – Name refers to “Guangxi Zhuang Autonomous Region” where the holotype was collected.
Holotype – MHZU 24–0828.
Saprobic on submerged decaying wood. Sexual morph: Undetermined. Asexual morph: hyphomycetes. Colonies on the natural substratum sparse, effuse, dark black, glistening, hairy. Mycelium superficial and partially immersed, composed of septate, dark brown, smooth hyphae. Conpaler towards the apex. Conidiogenous cells monoblastic, cylindrical, initially inderterminate, later becoming intercalary, pale brown, smooth, percurrent proliferation. Conidia 23–29 μm, diameter (x = 26.5 μm, n = 15), acropleurogenous, solitary, spherical, truncate at base, aseptate, initially olive-green, later brown to dark brown, guttules, smooth.
Culture characteristics – Conidia germinating on PDA within 12 h; Colonies growing on PDA, reaching 12 mm in 15 days at 25 °C, circular, rough, dry, raised, edge entire, with dense, velvety, white to pale gray mycelium, in reverse dark brown in the middle and white in the periphery.
Material examined – CHINA, Guangxi Zhuang Autonomous Region, Qinzhou city, on decaying wood from freshwater habitat, 1 June 2023, GX8.1 and GX8.2 (MHZU 24–0828, holotype; ZHKUCC 24–0794, ex-type).
GenBank – ZHKUCC 24–0794: PP693395 (LSU), PP693396 (SSU), PP695182 (tef1), PP695182(rpb2).
Notes – In the phylogenetic analysis (Fig. 2), Acrogenospora guangxiensis ZHKUCC 24–0794 shares a sister relationship to A. terricola PS3610. Morphologically, A. guangxiensis ZHKUCC 24–0794 is most similar to A. terricola PS3610 with spherical conidium. But they can be distinguished by length of conidiophores and color of conidia. Acrogenospora guangxiensis ZHKUCC 24–0794 produces olive-green to dark brown spores on the conidiophores and conidiophores length up to 475 μm, the microscopic morphology of the colony could not be obtained, while the morphology of A. terricola PS3610 from pine needles in MEA medium and produce dark brown to black pores throughout the conidiophores, and the conidiophores length is up to 900 μm (Harrington et al. 2022). Regarding DNA sequence data comparison, there is a discrepancy of 1.97% (16 out of 813) and 0.30% (3 out of 1006) in nucleotide variations within the LSU and SSU sequence, respectively, between A. guangxiensis ZHKUCC 24–0794 and A. terricola PS3610. Unfortunately, A. terricola does not have a publicly available protein sequence and cannot be compared.
Fig. 1 Acrogenospora guangxiensis (MHZU 24–0828, holotype). a, b Colonies on wood. c, d Conidiophores and conidia. e Conidia growth
location. f–l Conidia. m, n Colonies on PDA from above and reverse. Scale bars: c
=
100 μm, d, e
=
40 μm, f–l
=
20 μm
Figure 2