Acrogenospora olivaceospora D.F. Bao, Z.L. Luo, K.D. Hyde & H.Y. Su
Index Fungorum number: IF 557598; Facesoffungi number: FoF 07983
Holotype: MFLU 20–0290
Etymology: Referring to the conidia which are olive-green.
Saprobic on submerged decaying wood. Sexual morph: Undetermined. Asexual morph: Colonies effuse on natural substrate, hairy, dark brown. Mycelium mostly immersed, composed of grayish brown, septate, branched, smooth hyphae. Conidiophores 100–175 × 6–9 μm (x̄ = 137 × 7.4 μm, n = 20), mononematous, macronematous, solitary, erect, straight or slightly flexuous, cylindrical, indeterminate, unbranched, dark brown to olive, paler toward apex, septate, smooth. Conidiogenous cells holoblastic, monoblastic, integrated, initially terminal, later becoming intercalary, cylindrical, smooth, pale brown, proliferating percurrently. Conidia 32–37 × 28–33 μm (x̄ = 34.5 × 30.5 μm n = 30), acropleurogenous, solitary, subprolate to broadly ellipsoidal, base truncate, olive to black, aseptate, thick-walled, lacking guttules, smooth. (Desriptions from Bao et al. 2020)
Material examined: CHINA, Yunnan Province, Dali, Cangshan Mountain, on decaying wood submerged in a stream, March 2016, H.W. Shen, S-715 (MFLU 20–0290, holotype), ex-type culture, MFLUCC 20–0096.
Notes: In the phylogenetic analyses, Acrogenospora olivaceospora clustered with A. sphaerocephala (MFLU 18-1130 and MFLUCC 16-0179). However, A. olivaceospora differs from A. sphaerocephala by the shape, color and size of conidia. Acrogenospora olivaceospora has olive to black, subprolate to broadly ellipsoidal conidia, lacking guttules, while conidia of A. sphaerocephala are olive-green to brown, spherical or subspherical and guttulate. Acrogenospora olivaceospora is most similar to A. subprolata in having subprolate to broadly ellipsoidal, olive to black, aseptate, thick-walled conidia. However, A. olivaceospora has solitary conidiophores whereas those of A. subprolata are sometimes in small groups. In addition, the conidiophores of A. olivaceospora are shorter (102–172 × 5.8–9 vs. 150–300 × 9–12 μm) and the conidia are smaller (32–36.9 × 28–32.8 vs. 39–46 × 30–39 μm). (Notes from Bao et al. 2020)
Bao DF, McKenzie EHC, Bhat DJ, et al (2020) Acrogenospora (Acrogenosporaceae, Minutisphaerales) appears to be a very diverse genus. Front Microbiol 1606. https://doi.org/10.3389/fmicb.2020.01606
Fig 1. Acrogenospora olivaceospora (MFLU 20–0290, holotype). a,b. Colonies on wood. d,e. Conidiophores, conidiogenous cells, and conidia. f,g. Conidiogenous cells with conidia. Scale bars: a = 200 μm, b = 100 μm, c,d = 50 μm, e–g = 30 μm, h–j = 20 μm.
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