Acanthostigmina multiseptatum (Promp. & A.N. Mill.) Boonmee & K.D. Hyde

Yang, Yan-Yan, Thiyagaraja, Vinodhini, Wanasinghe, Dhanushka N., Ar, Gomes De Farias & Zhao, Qi, 2024, Phylogenetic and taxonomic appraisal of Neomanoharachariella xizangensis sp. nov. and the first asexual report of Acanthostigmina (Tubeufiaceae, Tubeufiales) from Xizang Autonomous Region, China, Phytotaxa 642 (2), pp. 127-140 : 134

Acanthostigmina multiseptatum (Promp. & A.N. Mill.) Boonmee & K.D. Hyde

Index Fungorum number: IF 550681, Facesoffungi number: FoF 15235

Basionym: Acanthostigma multiseptatum Promp. & A.N. Mill., Mycologia 102(3): 577 (2010)

Saprobic on the dead wood of an unidentified plant. Sexual morph: unidentified. Asexual morph: Hyphomycetous helicosporous. Colonies on the substratum superficial, effuse, gregarious, pale pink. Mycelium partly superficial, partly immersed, hyaline, septate, branched hyphae, with crowded masses. Conidiophores 137–166 µm × 2.4–3.7 µm (x̄ = 152 × 3 µm, n = 5), 1–2 µm wide at the apex, macronematous, mononematous, erect, straight, cylindrical, hyaline, unbranched, septate, smooth-walled. Conidiogenous cells 8–12 µm long, 3–4.3 µm wide (x̄ = 9.5 × 3.6 µm, n = 6), holoblastic, monoblastic, integrated, cylindrical, arising laterally from the conidiophores, smooth-walled. Conidia 166–219 µm × 5.7–8.9 µm in the broadest part (x̄ = 203 × 7 µm, n = 25), solitary, pleurogenous, helicoid, 30–40- septate, slightly constricted at the septa, tightly coiled 2 to 3 times, not becoming loose in water, rounded at the tip, 34–43 µm diam, tapering to 1.3–3.2 µm wide near the apex, 2.7–4 µm wide at the base, hyaline, shiny, guttulate, smooth-walled.

Culture characteristics: Conidia germinating on PDA and germ tubes produced from conidia within 8 h. Colonies growing on PDA, oval, edge irregular, raised, slightly sparse, reaching 5 mm in 1 week at 18 ℃, yellowish-brown in PDA medium, mycelium superficial and partially immersed, reverse yellowish-brown.

Material examined: China, Xizang Autonomous Region, Shigatse City, Nyalam County, 85.982237 N, 28.155186 E, on an unidentified dead wood. 6 July 2022, Yanyan Yang, YYY394 (HKAS 131155), living culture KUNCC 23- 15803.

Notes: In the combined phylogenetic analyses (LSU, ITS, tef 1-α, and rpb2), our isolate clustered with Acanthostigmina multiseptatum (ANM 665) with 91 ML/0.97 PP statistical support. Acanthostigmina multiseptatum was originally introduced as A. multiseptatum based on phylogenetic analyses along with unique morphological features, such as having longer asci and longer ascospores with more septa ( Promputtha et al. 2010). Based on morpho-molecular studies, Boonmee et al. (2014) transferred this species to Acanthostigmina . The base pair comparison between our new isolate and A. multiseptatum (ANM 665) revealed 0.99 % (526/529bp) differences in the ITS. Phylogenetic analyses coupled with morphological data, we reported our new isolate as the sexual morph of A. multiseptatum and the first asexual report of the genus. Acanthostigmina multiseptatum was also identified as the first geographical report from China.