Rhexoacrodictys erecta (Ellis & Everh.) W.A. Baker & Morgan-Jones, Mycotaxon

Shi, Lin, Yang, Hao, Hyde, Kevin D., Wijayawardene, Nalin N., Wang, Gen-Nuo, Yu, Xian- Dong & Zhang, Huang, 2021, Freshwater Sordariomycetes: new species and new records in Pleurotheciaceae, Pleurotheciales, Phytotaxa 518 (2), pp. 143-166 : 157

Rhexoacrodictys erecta (Ellis & Everh.) W.A. Baker & Morgan-Jones, Mycotaxon 82: 99 (2002)

Basionym: Mystrosporium erectum Ellis & Everh., J. Mycol. 4(6): 53 (1888)

Index Fungorum number: IF381123

Holotype: BPI 445573

FIGURE 5

Phaeoisaria species

Description: Saprobic on submerged wood. Sexual morph: Undetermined. Asexual morph: Colonies on natural substrata effuse, superficial, scattered, dark brown to black. Mycelium partly immersed and partly superficial, composed of septate, branched hyaline hyphae. Conidiophores macronematous, mononematous, erect, unbranched, straight or slightly flexuous, thick-walled, smooth, cylindrical, dark brown at the base, paler and narrower towards the apex, 6–8-septate, 31–85 × 4–6 μm (x = 56.9 × 4.7 μm, n = 15). Conidiogenous cells monoblastic, integrated, terminal, pale brown, smooth, cylindrical, 2.5–5 × 3–5.5 μm (x = 3.7 × 3.7 μm, n = 10), with percurrent extensions. Conidia acrogenous, solitary, dry, pyriform or obovoid, 26–33 × 18–21 μm (x = 30 × 20 μm, n = 15), muriform, often with multiple transverse and longitudinal or oblique septa, slightly constricted at septa, mature conidia dark brown to black, paler near the base; basal cell protruding, cylindrical, often with a marginal frill following secession.

Material examined: CHINA. Yunnan Province, Qiubei City, a small river in Puzhehei scenic area, on dead submerged decaying wood of an unidentified plant, 23 June 2018, Hao Yang, P 45 ( IFRD 500-016 ), living culture KUMCC 20-0194 .

Notes: Xia et al. (2017) designated a reference specimen for this species and conducted phylogenetic analyses, which showed that Rhexoacrodictys was affiliated to Savoryellaceae (Savoryellales) . However, it clustered in Pleurotheciaceae , Pleurotheciales when more species were added to phylogenetic analysis ( Luo et al. 2019). In this study, we collected a specimen from submerged wood in a small river in Puzhehei, Yunnan Province, China, which matches well the type material of R. erecta in morphology. Our collection shares the identical LSU sequence with the reference specimen of R. erecta and ITS sequence of our strain KUMCC 20-0194 differs from HSAUPmyr4622 by one nucleotide. In our phylogenetic tree, Rhexoacrodictys clustered in Pleurotheciaceae (Pleurotheciales) agreeing with Luo et al. (2019).

Phaeoisaria species

Figures

FIGURE 5. Rhexoacrodictys erecta (IFRD 500-016) a, b Colonies on wood. c Conidiophore with attached conidium. d Conidiophore with conidium e Conidiophore f Conidiogenous cells with conidia.g–j Conidia.k Germinating conidium. l, m Colony on PDA from above and reverse. Scale bars: c–e, k = 20 μm, f–j = 10 μm.