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Page number:135 
Remarks (internal):Cladosporium pseudiridis closely resembles C. iridis, a common and widespread species causing leaf spots on numerous Iris spp. and a few additional hosts of the host family Iridaceae, but the latter species is easily distinguishable by having longer and narrower, more frequently septate conidia, (18-)30-75(-87) x (7-)10-16(-18) μm, (0-)2-6(-7)-septate.
It is unlikely that C. pseudiridis is of New Zealand origin since the genus Iris is not indigenous to New Zealand. All Iris species that are found in this country have been introduced, mainly for horticultural purposes. The species is, therefore, probably more common than indicated above. However, within the course of the recent monographic studies in the genus Cladosporium numerous herbarium specimens, mainly of European origin, have been examined and proved to be correctly identified agreeing with the species concept of C. iridis. Additional collections and cultures are necessary to determine its distribution.
Description type:Original description 
Description:Cladosporium pseudiridis K. Schub., C.F. Hill, Crous & U. Braun, sp. nov. MycoBank MB504576. Figs 29-30
Mycelium sparingly branched, 2-7 μm wide, septate, not constricted at the septa, subhyaline to pale brown, smooth or almost so, walls somewhat thickened, guttulate or protoplasm appearing granular, sometimes enveloped by a slime coat. Conidiophores arising mostly terminally from ascending hyphae, sometimes also laterally from plagiotropous hyphae, erect, more or less straight, broadly cylindrical-oblong, once or several times slightly to distinctly geniculate-sinuous, forming more or less pronounced lateral shoulders, nodulose, unbranched, 100-320(-500) x 7-11 μm, swellings 10-14 μm wide, becoming narrower and paler towards the apex, septate, not constricted at the septa, septa mainly basal, apical cell often very long, pale to medium olivaceous-brown, subhyaline at the apex, smooth or almost so, sometimes minutely verruculose, walls usually distinctly thickened, sometimes even two-layered, up to 1(-2) μm thick, protoplasm granular, often clearly contrasting from the outer wall. Conidiogenous cells integrated, terminal and intercalary, cylindrical-oblong, slightly to distinctly geniculate-sinuous, nodulose with conidiogenous loci confined to swellings or lateral shoulders, 30-110 μm long, proliferation percurrent to sympodial, with a single or three, sometimes up to five geniculations per cell, usually only a single locus per swelling, protuberant, very prominent, short cylindrical, peg-like, clearly composed of a dome and surrounding rim, dome often higher than the periclinal rim, broad, somewhat paler than rim, conically narrowed, (2-)2.5-4 μm wide, up to 2 μm high, thickened and darkened-refractive.
Conidia solitary, sometimes in short unbranched chains of two or three, straight to slightly curved, young conidia small, 0-1-septate, broadly ovoid to pyriform, 15-26 x (9-)11-16(-18) μm [av. ± SD, 19.2 (± 4.3) x 14.2 (± 3) μm], first septum somewhat in the upper half, the upper cell is much smaller but gradually extending as the conidium matures, mature conidia 1-3-septate, broadly pyriform,
cylindrical-oblong or soleiform, usually with a distinctly bulbous base, 30-55 x 12-19(-21) μm [av. ± SD, 41.5 (± 6.8) x 17.1 (± 2.1) μm], broadest part of conidia usually at the bulbous base, mostly attenuated towards the basal septum, septa becoming sinuous with age, pale to medium olivaceous-brown or brown, usually echinulate, sometimes coarsely verrucose, walls distinctly thickened, up to 2 μm thick, often appearing layered with a large lumen in the centre of the cell, broadly rounded to flattened at apex and base, hila often very prominent, often peg-like elongated, up to 3 μm long, with age becoming less prominent, visible as a thickened flat plate just below the outer echinulate wall layer, slightly raised towards the middle, 2-3.5 μm diam, thickened and darkened-refractive; microcyclic conidiogenesis not observed.
Cultural characteristics: Colonies on PDA attaining 6 mm diam after 14 d at 25 °C, whitish, smoke-grey to pale olivaceous-grey due to abundant aerial mycelium, olivaceous-black reverse, margin narrow, white, more or less crenate, aerial mycelium zonate, fluffy, covering most of the colony, mainly in the colony centre, growth convex to raised, deep into the agar, with age few large prominent exudates formed, sparingly sporulating. Colonies on MEA attaining 7 mm diam after 14 d at 25 °C, olivaceous-grey, pale olivaceous-grey to pale rosy-buff due to abundant aerial mycelium covering almost the whole colony, iron-grey reverse, margin colourless or white, broad, regular, more or less glabrous, aerial mycelium fluffy, dense, high, growth convex to umbonate, sometimes with elevated colony centre, prominent exudates lacking, sporulation sparse. Colonies on OA attaining 8 mm diam after 14 d at 25 °C, white, pale buff to pale olivaceous-grey in the centre, margin grey-olivaceous, olivaceous- to iron-grey reverse, margin entire edge or somewhat undulate, somewhat feathery, growth raised with a somewhat depressed centre forming an elevated outer rim, without prominent exudates, sporulation more abundant.
Specimen examined: New Zealand, Auckland, Mt. Albert, Carrington Road, Unitec Campus, isolated from large leaf lesions on Iris sp. (Iridaceae), 15 Aug. 2004, C.F. Hill, CBS-H 19861, holotype, culture ex-type CBS 116463 = LYN 1065 = ICMP 15579.
Substrate and distribution: On living leaves of Iris sp.; New Zealand.

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