Dictyosporium phellodendri S. P. Zou, Y. P. Xiao & Y. Z. Lu 2026, sp. nov.

Dictyosporium phellodendri S. P. Zou, Y. P. Xiao & Y. Z. Lu sp. nov. Fig. 5 Etymology. The specific epithet “ phellodendri ” refers to the host genus name “ Phellodendron ” from which the fungus was isolated. Holotype. HKAS 149888. Description. Saprobic on dead wood of Phellodendron amurense. Sexual morph Undetermined. Asexual morph Hyphomycetous. Colonies on natural substrate forming sporodochial conidiomata, superficial, punctiform, scattered, black, glistening. Mycelium immersed, pale to brown. Conidiophores 3–5 μm wide, micronematous, simple, aseptate, cylindrical, hyaline to pale brown, thin-walled. Conidiogenous cells 5–8 × 3–6 μm (x ̄ = 6.3 × 4.7 μm, n = 10), holoblastic, hyaline or pale brown, cylindrical. Conidia 17–44 × 15–27 μm (x ̄ = 30 × 21 μm, n = 30), acrogenous, cheiroid, complanate, smooth-walled, pale brown or pale yellow, mostly consisting of four closely adpressed rows of cells, rarely with three or five rows, 33–38 × 4–6 μm (x ̄ = 35.5 × 5.5 μm, n = 30), 4–10 - euseptate in each row, with hyaline, tubular, elongated apical appendages arising from two outer rows, 13–58 × 3–6 μm (x ̄ = 32.9 × 4.2 μm, n = 15). Culture characteristics. Conidia produce germ tubes on PDA within 18 hours of incubation at 25 ° C. Colonies on PDA are circular, with a flat surface and entire edge, reaching a diameter about 28 mm after 39 days of incubation at 25 ° C. The colony appears white on the top view, while the reverse side with pale grey centre and yellow edge. Material examined. China • Guizhou Province, Guiyang City, Anshun City, Xixiu District, Yaowang Valley, 26°16'17"N, 106°7′0"E, on the rotting branch of Phellodendron amurense, 15 October 2024, Shi-Ping Zou, HBYWGC 13 (HKAS 149888, holotype), ex-type culture GZCC 25-0522 • Ibid., HBYWGC 25 (149889), living culture GZCC 25-0523. Notes. In the phylogenetic analysis, Dictyosporium phellodendri (GZCC 25-0522 and GZCC 25-0523) formed a sister clade to D. muriformis with 80 % ML / 0.98 PP (Fig. 2), but D. muriformis, possesses smaller conidia (20–30 × 11–14.5 μm vs. 26–32 × 15–25 μm), darker pigmentation (median brown vs. pale brown or pale yellow) and the absence of appendages (Hyde et al. 2020). Morphologically, D. phellodendri is most similar to D. alatum (ATCC 34953) in conidial shape. However, it is distinguished by its larger conidia (17–44 × 15–27 μm vs. 26–32 × 15–25 μm), paler colouration and 4–10 septa per row (Van Emden 1975). Furthermore, comparisons of sequences between D. phellodendri and D. alatum (ATCC 34953) revealed differences in the ITS region of 13 % (64 / 507 bp, including 11 gaps) and in the LSU region of 3 % (18 / 573 bp, with 4 gaps). We, therefore, designated our collections as a new species, based on morphological and phylogenetic evidence.