Cladosporium chusqueae P. P. Costa, A.W.C. Rosado & O.L. Pereira

Costa, Pricila P., Rosado, André W. C. & Pereira, Olinto L., 2022, Six new species of Cladosporium associated with decayed leaves of native bamboo (Bambusoideae) in a fragment of Brazilian Atlantic Forest, Phytotaxa 560 (1), pp. 1-29 : 21

Cladosporium chusqueae P. P. Costa, A.W.C. Rosado & O.L. Pereira sp. nov. ( Figure 6 )

MycoBank: MB824724

Systematic position: Fungi, Ascomycota, Pezizomycotina, Dothideomycetes, Dothideomycetidae, Cladosporiales, Cladosporiaceae

Etymology:—Name refers to the genus Chusquea , from which the species was isolated.

Colonies on PDA attaining 52 mm diam, smoke grey, furrowed, submerged mycelium at the margin, velvety, sparse woolly mycelium central; reverse greenish grey, dull green at the margin. Colonies on MEA attaining 49 mm diam, grey olivaceous, velvety, sparse feathery mycelium central; reverse dull green. Colonies on OA attaining 53 mm diam, greenish-grey to glaucous grey, greenish glaucous at the border, fluffy, woolly on center, sector formation grey olivaceous, velvety; reverse dull green, with a light citrine to pure yellow, diffusible pigment. Colonies on SNA attaining 34 mm diam, greenish glaucous to olivaceous buff, flat and scares; reverse similar to surface. Mycelium loosely branched, 2.06–4.10 µm wide, septate, subhyaline to light brown, sometimes slightly swollen and darker brown near the origin of conidiophores, irregularly rough-walled. Conidiophores macronematous, solitary, 22.98–140.70 × 2.58–4.39 µm, arising terminal and laterally from hyphae, erect, flexuous, or bent, once dichotomously branched immediately before a septum at 90° angle, frequently cylindrical oblong, sometimes cylindrical attenuated towards the apex, some loci formed on the lateral shoulder or slight geniculate, sometimes slightly head-like, unilaterally swollen at the apex, brown or pale brown, unbranched, 0–7 septate, conspicuous at the base clearing towards the apex, more or less rough-walled, sometimes micronematous, lateral, 7.61–19.46 × 2.40–2.83 µm pale brown to brown, rarely subhyaline, narrower, 1–3 loci, 0–2 septate. Conidiogenous cells integrated, mainly terminal, sometimes geniculate towards the apex, rarely with loci formed on the minute lateral shoulder, 8.61–21.92 × 2.39–4.01µm, pale brown to brown, with 1–5 loci at apex, rarely 8, non-protuberant or only slightly so, somewhat thickened and darkened. Ramoconidia absent. Secondary ramoconidia ellipsoid to subcylindrical, 2–4 distal hila, 5.5–12.04 × 2.01–3.51 µm, aseptate, pale brown to brown, sometimes very similar to conidium, just a little bigger. Conidia numerous, catenate, acrogenous, fusiform, ellipsoid to narrowly ellipsoid-ovoid, aseptate, subhyaline to pale brown, intercalary conidia 3.81–7.34 × 1.81–2.53 µm, 1–2 distal hila, terminal conidia oblong-ellipsoid, 2.84–5.53 × 1.80–2.45 µm. Microcyclic conidiogenesis occurs.

Type:— Brazil. Minas Gerais: Araponga, at “ Parque Estadual Serra do Brigadeiro ”, isolated from decayed leaf of Chusquea urelytra (Poaceae) , March 15, 2016 (holotype VIC 44239 , ex-type culture COAD 2258) .

GenBank: MT373122 (ACT), MT680201 (TEF1-α), MZ 318430 (rDNA-ITS)

Additional specimens examined:— BRAZIL. Minas Gerais:Araponga, at “Parque Estadual da Serra do Brigadeiro”, isolated from decayed leaves of Chusquea urelytra (Poaceae) , 15 March 2016, (living culture COAD 2261 and COAD 2262).

Notes: — Cladosporium chusqueae is phylogenetically close to C. angulosum and C. xantochromaticum and has common features with both species. Similar to C. angulosum , C. chusqueae branches dichotomically near the base of the conidiophore, forming an angle of 90º. This branching occurs immediately before the septum, similar to the branches of the C. xantochromaticum . The unusual diffusible yellowish pigmentation in the culture medium was also observed in C. chusqueae as well as in C. xantochromaticum . However, this pigment was observed only in OA, whereas C. xantochromaticum was found only in the PDA medium. Unlike the two related species, ramoconidium was not observed for C. chusqueae .

Figures

FIGURE 6. Cladosporium chusqueae (VIC 44239, holotype). A–D. Colonies on A. Potato dextrose agar; B. Malt extract agar; C. Oatmeal agar; D. Synthetic nutrient-poor agar, after 14 days at 25 ºC, under near-ultraviolet light, respectively.E–K. Macronematous conidiophores and conidia. G. Terminal conidiophore. H. Short peg-like prolongation. I. Bent conidiophore; J–K. Conidiophore branched near the base at a 90º angle. L. Micronematous conidiophores. M. Microcyclic conidiogenesis. Scale bars: E = 50 µM; F–M = 20 µM.