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Family: PleosporaceaeGenus: Alternaria
Anamorph: conidiomata absent. Conidiophores amphigenous, 60-80 x 4.5-6 µm, cylindrical, thick-walled, dark brown, septate, unbranched or branched near the apex, the fertile region to ca 10 µm long, somewhat paler and thinner-walled, rather irregular in form, with poroid conidiogenous loci to ca 1.5 µm diam. that are usually distinctly protuberant. Conidia 29-44 x 14.7-18.5 µm, ± ellipsoidal with a basal beak to ca 13 µm in length and 4 µm diam., dark brown, very thick-walled, with 3-4 transverse septa and 1 (-2) incomplete longitudinal septa, the cells somewhat inflated; probably catenate but chains not observed in the material studied.
Teleomorph: ascostromata perithecial, epigenous, 140-190 µm diam., ± globose, strongly papillate, erumpent through the host epidermis. Peridium composed of an outer portion of 5-6 layers of angular to epidermoid cells to ca 8 µm diam., mostly occluded by rather amorphous melanized material, and an inner pale brown layer. Interascal tissue well-developed, of rather thick-walled branched and anastomosed pseudoparaphyses to ca 2.5 µm diam. Asci in a basal fascicle, 105-135 x 12-14 µm, cylindrical, fairly short-stalked, thick-walled and fissitunicate, the apex rounded with a distinct ocular chamber, 8-spored. Ascospores obliquely uniseriate to biseriately arranged, 16.5-22.5 x 7.5-9 µm, clavate-cylindrical to clavate-ellipsoidal, usually with five transverse septa and a single incomplete longutidinal septa that usually does not divide the apical cells, slightly constricted at the septa and slightly more so at the primary septum, golden to mid brown, very thick-walled, smooth, wihout a gelatinous sheath or appendages.