Curvularia moniliformis Madrid, Cantillo, & R. Castillo sp. nov. (Fig. 5)
MycoBank number: MB 551454; Index Fungorum number: IF 551454; Facesoffungi number: FoF 10418;
Etymology: The name refers to the abundant moniliform hyphae produced by this fungus in culture.
Vegetative hyphae septate, branched, light olivaceous to mid olivaceous brown, thin- to thick-walled, smooth, mostly 1–8 µm wide, with moniliform segments composed of swollen melanized cells up to 15 µm wide, anastomosing. Sexual morph: Undetermined. Asexual morph: Conidiophores macronematous, mononematous, solitary, septate, simple, straight to flexuous, strongly geniculate at the fertile part, light olivaceous brown to dark brown, often paler at the apex, smooth to verruculose, with cell walls often thicker than those of the supporting vegetative hyphae, 70–230 × 5–8 µm. Conidiogenous cells integrated, terminal and intercalary, subcylindrical to irregularly, mono to polytretic, proliferating sympodially, 4–12 µm long. Conidia mostly subcylindrical or narrowly ellipsoid, straight, light olivaceous brown to mid golden brown, with a small pale area at each pole, verruculose, 21–32(–36) × 9–14 µm, constantly 3–distoseptate, with rounded to subtruncate poles. Hilum somewhat thick and dark.
Material examined: CHILE, Metropolitan Region, Río Clarillo National Park, isolated from unidentified species of Poaceae, 26 August 2016, H. Madrid & L. Linaje (SGO 168421, holotype), ex-type living culture HM 100.
Notes: BLAST searches of sequences from this collection showed closest match Curvularia buchloes (CBS 246.49, ex-type strain); ITS sequence [GenBank KJ909765] shows 100% similarity and GPDH sequence [GenBank KM061789] shows 99.55% similarity. This species has longer and narrower conidia (27–86 × 8–11 µm) which often appear distinctly curved and have nine distosepta (Sivanesan 1987). Another close match was Curvularia spicifera (CBS 199.31) which has 100% similarity with ITS sequence (GenBank LT631349) and 98.36% similarity with GPDH (GenBank LT715815). The conidia of this species are very similar to those of C. moniliformis, but according to Ellis (1971) and Sivanesan (1987) they are smooth-walled.
Figure 5 – Curvularia moniliformis (SGO 168421, holotype). a, b. Conidia attached to conidiogenous cells. c-h. Conidia. i. Swollen melanized cells. Scale bars: a, i = 40 µm, c-g = 10 µm, b, h = 30 µm.