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Page number:139 
Remarks (internal):In conidium morphology, the new taxon is close to Helminthosporium chlorophorae M.B. Ellis and Helminthosporium kakamegense Siboe et al. However, H. chlorophorae has stromata, the tips of its conidiophores are swollen. The conidia of H. kakamegense are obviously smaller. The new taxon can be separated from other species in the genus Helminthosporium by its subhyaline, black-tipped conidia. The typically thin-obclavate conidium shape is also very helpful in distinguishing it from other species in the genus with obclavate,
obpyriform or ovoid conidia.
 
Description type:Original description 
Description:Helminthosporium subhyalinum Meng Zhang & T.Y. Zhang, sp. nov.
Mycobank MB510408 figure 2
Mycelium immersed in the substratum. Stromata not formed. Conidiophores single or in fascicles, simple, subcylindrical, straight or flexuous, septate, smooth-walled, brown, paler towards the apex, 120-200 µm long, 6-8.5 µm wide above the base which is swollen to 10-12 µm wide, sometimes slightly inflated at the tip, with 1-3 well-defined, small pores at the apex and a few formed laterally beneath the upper septa. Conidia tretic, arising through pores at the apex and laterally beneath the upper septa, straight or flexuous, thinly obclavate, smooth-walled, subhyaline, 6-9 pseudoseptate, 72-125 (av. 100) µm long, 9.0-11.5 (av. 10.6) µm thick in the widest part, narrowing towards the apex to 2.5-5 µm, black at the tip, with a dark blackish-brown scar at the base.
Colonies in tap water agar + wheat straw (TWA+W) grey to brown, velvety, effuse, conidia not formed. In PDA-filter paper, sporulating freely. Mycelium subhyaline to brown, septate black, branched, smooth-walled. 1.5-6 µm thick. Conidia straight or flexuous, thinly obclavate, smooth-walled, 7-10pseudoseptate, 54-100 (av. 86) µm long, 8-10 (av. 8.6) µm thick in the widest part, narrowing towards the apex to 2.5-5 µm, black at the tip, with a dark
blackish-brown scar at the base.


 
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