Craspedodidymum hunanense L.L. Liu & Q.R. Li, 2024

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 : 48-49

Craspedodidymum hunanense L.L. Liu & Q.R. Li sp. nov. ( Fig. 2 )

Mycobank number: MB 855778

Etymology: Referring to the location “ Hunan Province, China ” where the fungus was collected.

Typus: CHINA, Hunan Province, Zhangjiajie City, Sangzhi County, Badagong Mountain National Nature Reserve , 105°5′5.68′′E, 29°48′27.06′′N, altitude: 1288 m, on a decaying twig, 26 August 2023, L.L. Liu, 2023BD22 (GMB5302, holotype; KUN-HKAS 136275, isotype; GMBC5302 ex-type culture) .

Saprobic on decaying twigs. Sexual morph: Undetermined. Asexual morph: Colonies on natural substratum effuse, brown to black, hairy. Mycelium partly immersed, irregular, achaetous, hyphopodia absent. Conidiophores 250–400 μm (x̅ = 325.5 μm, n = 20) long, 10.5–14.5 μm (x̅ = 13.9 μm, n = 20) wide near the base, 5.5–8 μm wide (x̅ = 6.7 μm, n = 20) at the narrow part, macronematous, mononematous, solitary, unbranched or sporadically branched at the apex, scattered, erect, straight or slightly flexuous, smooth, septate, thick-walled, brown to dark brown, paler towards the apex, slightly swollen at the base. Conidiogenous cells 25–38 μm (x̅ = 29.4 μm, n = 20) long, 12–15.5 μm (x̅ = 13.4 μm, n = 20) wide, integrated, terminal, monophialidic, sub-hyaline or pale brown, extending percurrently, subcylindrical, swollen at the subapical region, with a collarette at the apex. Collarette funnel-shaped, 7.5–9 μm (x̅ = 8.4 μm, n = 20) high, 10.5–12 μm (x̅ = 11.2 μm, n = 20) wide. Conidia 11–19.5 (x̅ = 17.4 μm, n = 30) long, 9.5–13.5 μm (x̅ = 11.3 μm, n = 30) wide, ellipsoidal, oblong, aseptate, dark-brown, thick-walled, without appendages, smooth, sometimes slightly tapering towards the base.

Culture characteristics: Conidia germinated on water agar within 12h. Colonies growing on PDA at 25℃, reached 10–20 mm diam. after 3 weeks, convex, margin undulate, velvety, mucoid towards the margin, white with paler zones of sparse growth, zonate, reverse pale ochre.

Additional specimen: China, Hunan Province, Zhangjiajie City, Sangzhi County, Badagong Mountain National Nature Reserve , 105°5′5.08′′E, 29°48′27.67′′N, altitude: 1292 m, on a decaying twig, 26 August 2023, L.L. Liu, 2023GS23 (GMB5303; GMBC5303) .

Notes: Craspedodidymum is characterized by macronematous, mononematous simple, or branched conidiophores with integrated, terminal, enteroblastic, cylindrical conidiogenous cells show apical swelling. Additionally, possessing a large and distinctive funnel-shaped terminal collarette. ( Holubová-Jechová 1972, Ellis 1976, Yanna et al. 2000, Réblová & Nekvindová 2023). Craspedodidymum hunanense is mostly similar to C. fujianense ( Ma et al. 2011) , which was found on dead branches of Acacia confusa Merr. ( Mimosaceae ) from Fujian Province, China. In the phylogenetic tree ( Fig. 1 ), C. hunanense forms an independent branch and sister to C. elatum . However, C. elatum differs from C. hunanense by its dichotomously multiply branched ( Holubová-Jechová 1972).

Figures

FIGURE 1. Phylogram generated from maximum likelihood analysis based on combined ITS, LSU, TEF1-α sequence data. Ellisembia aurea (CBS 144403) and E. folliculate (CBS 147152) were used as the Outgroup taxa. Bootstrap values equal to or greater than 75% and Bayesian posterior probabilities equal to or greater than 0.95 are given next to the nodes.The type strains were indicated in bold, and newly generated sequences were indicated in red.

FIGURE 2. Craspedodidymum hunanense (GMB5302, holotype) a–c Colony on wood. d–f Conidiophores and conidia. g, h Conidiogenous cells with conidia. i–l Conidia. m Germinated conidium. n, o Surface and reverse view of culture on PDA. Scale bars: a = 0.3 mm, b,c = 0.1 mm, d, e, m = 50 μm, f–l = 10 μm.