Camposporium guizhouense L. L. Liu & Z. Y. Liu 2025, sp. nov.

Camposporium guizhouense L. L. Liu & Z. Y. Liu sp. nov. Fig. 5 Etymology. Refers to the location where the holotype was collected. Holotype. GZAAS 20-0375. Description. Saprobic on decaying, submerged wood in freshwater habitats. Asexual morph. Colonies on natural substrates are velvety, effuse, hairy, scattered, brown, and glistening. Mycelium partly immersed, partly superficial, hyaline to pale brown, septate, and cylindrical. Conidiophores macronematous, mononematous, irregularly cylindrical, straight to flexuous or twisted, erect, pale to mid-brown, sometimes fading slightly towards the apex, smooth-walled, unbranched, 3–9 - septate, 60–110 × 4–6.5 μm (x ̄ = 80 × 5 μm, n = 20). Conidiogenous cells were holoblastic or polyblastic, integrated into the apical region of the conidiophore, denticulate, cylindrical, pale brown, smooth-walled, and sometimes attached to the conidia following detachment. Conidia solitary, cylindrical to narrowly fusoid, elongate, brown or pale brown, 58–81.5 × 7–9 μm (x ̄ = 70 × 8 μm, n = 20), paler at both ends, verrucose, thickened walls, 8–11 - septate (mostly 10), basal cell conical with a truncate end, apical cell rounded with two independent, simple, cellular, aseptate, hyaline, smooth, straight, curved, or flexuous appendages, 24.5–47.5 × 1.5–3.5 μm (x ̄ = 35 × 2 μm, n = 20). Sexual morph. Undetermined. Cultural characteristics. Conidia germinated on WA within 24 h, and germ tubes were produced from the apex. Colonies on PDA reached approximately 25 mm diam. after 3 weeks at 25 ° C in dark, circular, grey-white, or yellowish mycelium, dense in the middle and sparse in the edge, in reverse, pale brown to brown, smooth in the margin. Material examined. China • Guizhou Province, Guiyang City, Aha Lake, near 26°32'N, 106°40'E, at 1085 m altitude, on a decaying branch submerged in the lake, 16 April, 2018, L. L. Liu, 18 A-8 (GZAAS 20-0375, holotype); • ex-type living culture, GZCC 19-0480. Taxonomic notes. Phylogenetic analyses of the combined LSU, SSU, ITS, and tef 1 - α sequence dataset showed that C. guizhouense was sister to C. ramosum (CBS 132483) and formed a distinct lineage. We compared the ITS sequences of the new taxon (GZCC 19-0480) to that of C. ramosum (CBS 132483). A difference of 7.87 % (37 / 470 bp) was observed. Additionally, comparing 812 nucleotides across the LSU gene region between GZCC 19-0480 and C. ramosum (CBS 132483) revealed 13 base pair differences (1.60 %). Morphologically (Table 3), C. guizhouense conidia resemble C. dulciaquae, C. fusisporum, C. ramosum, and C. septatum conidia in shape. However, the conidia of C. guizhouense (58–81.5 × 7–9 μm) are considerably smaller than those of C. dulciaquae, C. fusisporum, C. ramosum, and C. septatum (100–130 × 8.5–13, 98–125 × 7–11.5, 80–112 × 6.4–9.6, and 86–115 × 13.5–19 μm, respectively). Moreover, the conidia of C. guizhouense have two simple and aseptate apical appendages; those of C. dulciaquae, C. fusisporum, and C. septatum have 2–3 apical appendages, and those of C. ramosum have 1–3 simple or branched septate appendages. Therefore, we introduce our collection as a new species, C. guizhouense.