Aquadictyospora clematidis Phukhams., D.J. Bhat & K.D. Hyde

Liu, Lili, Zhang, Qinfang, Ren, Yulin, Yang, Qing, Li, Qirui, Lin, Chuangen, Cheewangkoon, Ratchadawan, Liu, Hongmei & Samarakoon, Milan C., 2024, Craspedodidymum hunanense sp. nov. (Chaetosphaeriaceae, Chaetosphaeriales) and a new record of Aquadictyospora clematidis (Dictyosporiaceae, Pleosporales), from Hunan Province, China, Phytotaxa 675 (1), pp. 43-58 : 52

Aquadictyospora clematidis Phukhams., D.J. Bhat & K.D. Hyde , Fungal Diversity 102: 17 (2020)

Mycobank number: MB 557125

Saprobic on decaying twigs of an unknown plant. Sexual morph: Undetermined. Asexual morph: Hyphomycetous. Conidiomata on natural substrate forming sporodochial conidiomata, 150–390 × 230–450 μm (x̅ = 200 × 340 μm, n=15), superfcial, compact, scattered, subglobose to oval, dark brown to black, velvety. Mycelium immersed, consisting of branched septate hyphae, 2–3 μm wide, smooth, thin-walled, hyaline. Conidiophores micronematous, reduced, hyaline to pale brown, smooth. Conidiogenous cells 8.8–11.5 × 3.5–4.7 μm (x̅ = 9.8 × 4 μm, n = 20), holoblastic, monoblastic, discrete, solitary, determinate. Conidia 34.5–39.8 × 18.7–22.4 μm (x̅ = 36.5 × 20.7 μm, n = 30), dictyosporous, appearing broadly rounded in upper half compactly depressed, obovoid, composed of uniformly medium brown heavily pigmented at the upper half, smooth with hyaline mammiform basal cell 12.5–20.5 × 11.3–12.7 μm (x̅ =17.1 × 11.7 μm, n = 20) not complanate, secession schizolytic, conidial appendages absent.

Culture characteristics: Conidia germinated on WA medium within 12 hours. Colonies on PDA medium reached a diameter of 20–25 mm after 3 weeks at 28℃ in darkness. These colonies appeared subcircular and convex, producing a yellow pigment, with a wrinkled surface and velvety yellowish-white mycelium. The reverse side exhibited a dark brown to dark yellow coloration with a smooth margin.

Material examined: CHINA, Hunan Province, Zhangjiajie City, Sangzhi County, Badagong Mountain National Nature Reserve , 105°5′5.79′′E, 29°48′26.56′′N, altitude: 1278 m, on a rotting branch, 26 August 2023, L.L. Liu, 2023BDGS14 (GMB5301; GMBC5301) (New geographical record in China) .

Notes: Aquadictyospora was introduced to accommodate A. lignicola ( Li et al. 2017) . The genus is characterized by its superficial sporodochial conidiomata, which are circular or oval in shape. It possesses micronematous conidiophores with monoblastic conidiogenesis cells and uniformly medium brown dictyosporous conidia featuring a subglobose, hyaline cell at the basal end ( Li et al. 2017, Phukhamsakda et al. 2020). The morphological features observed in our specimen ( Fig. 4 ) closely align with A. clematidis . Moreover, the molecular data indicated consistency with A. clematidis ( Phukhamsakda et al. 2020) . A BLASTn search against GenBank revealed that the ITS, LSU, and SSU sequences matched the ex-type of A. clematidis with 100% similarity, while the TEF1-α sequence exhibited 98% similarity. Therefore, we concluded that our new collection belongs to A. clematidis . Originally, Aquadictyospora clematidis was reported from Thailand (Nan Province) ( Phukhamsakda et al. 2020). It is considered a newly recorded species in China.

Figures

FIGURE 4. Aquadictyospora clematidis (GMB5301) a–c Colony on wood. d–f Conidiophores with conidia.g Germinated conidium.h–k Conidia. l, m Surface and reverse view of culture on PDA. Scale bars: a = 0.5 mm, b,c = 0.1 mm, d,e = 50 μm, f = 20 μm, g–k = 10 μm.