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 Add this item to the list   805921 Original description
   
Remarks (public):Due to the formation of true synnemata, denticulate conidiogenous cells and pale pluriseptate conidia, the Vietnamese hyphomycete, collected on fallen leaves of an unidentified tree species, may easily be identified as member of Atractilina (Deighton & Pirozynski 1972, Ellis 1976, Seifert et al. 2011). Only a few species have been assigned to this genus, including some non-synnematous species which are probably not congeneric. Deighton & Pirozynski (1972) introduced the combination Atractilina asterinae (Hansf.) Deighton & Piroz. for a species hyperparasitic on sooty molds in Africa. This species is non-synnematous, i.e. it forms solitary conidiophores, and the conidia are distoseptate. Therefore, it is very doubtful if this species has been correctly assigned to Atractilina. A. hymenaeae Bat. & J.L. Bezerra (Batista et al. 1961), described from Brazil on Hymenaea sp., associated with Asterina and Asteridiella spp., is also non-synnematous and very probably not correctly placed in Atractilina. A. alinae roughly resembles A. parasitica (G. Winter) Deighton & Piroz. (Deighton & Pirozynski 1972, Ellis 1976), a hyperparasitic species widespread in tropical countries, but the latter species has quite distinct conidia which are longer, 35–50 µm, mostly 3-septate, often minutely verruculose and slightly pigmented with age, frequently with beak-like apex and a terminal small knob. The synnemata are up to 1.5 mm long and 40 µm wide. A. calycini Jana, A.K. Das & S.N. Ghosh (Jana et al. 2006), described from India on living leaves of Neurocalyx calycinus, is morphologically very close to A. parasitica and said to be distinguished by shorter synnemata, up to 900 µm, occasionally branched conidiophores wider near the apex, and smaller, always smooth conidia without terminal knob. The ecology of this species is unclear and not properly specified. In the description, A. calycini is classified to be hyperparasitic, but its mycelium is described to grow superficially on living leaves. Other fungi on the host on which this species might be developed as hyperparasite are not mentioned. A. biseptata R.F. Castañeda (Castañeda-Ruiz 1986) is a true synnematous Atractilina species, but differs from the Vietnamese fungus in having consistently 2-septate conidia. 
Description type:Original description 
Description:Conidiomata synnematous on the natural substrate, solitary, scattered, dark brown to blackish. Synnemata determinate, up to 500 µm long, composed of a firm, brown, subcylindrical stalk, 10–25 µm wide, base often somewhat wider, up to 30 µm, and a rather compact, paler head, subglobose on outline, up to 80 µm diam., individual appressed filaments of the stalk 1.5–4 µm wide, pigmented, septate throughout, wall smooth, thin to slightly thickened, filaments apically slightly to moderately splaying out, occasionally branched, free part up to 45 µm long and 2.5–5 µm wide, pale to medium brown, tips often paler; conidiogenous cells integrated, terminal, up to 35 µm long, polyblastic, with a single or several distinct denticles, proliferation sympodial; denticles subcylindrical to usually conical, 1–2 × 0.8–1.5 µm, apex truncate, thin-walled. Conidia formed singly, broadly fusiform, ellipsoid, attenuated towards base and apex, (20–)30–35(–40) × (3–)4–7 µm, (2–)4–7-septate, septa thin and rather inconspicuous, subhyaline to faintly yellowish green, thin-walled, smooth or almost so, apex subobtuse to pointed, base obconically truncate, hila 1–1.5 µm wide, neither thickened nor darkened or only slightly darkened by being refractive. 
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