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Page number:147 
Remarks (internal):Nag Raj (1977b) revised Acanthotheciella Höhn. and its conidial states, Ypsilonia. Four species were accepted in Ypsilonia, Y. mirabilis (Speg.) Nag Raj, Y. tropicalis Nag Raj (= Psalidosperma mirabile Syd.), Y. cuspidata Lév., and the Ypsilonia state of A. barbata (Pat.) Höhn. Unfortunately revision of the Acanthotheciella species did not take account of Setella xyphopaga Viégas (1944) and Gilmania pulchra Batista & Cavalcanti apud Batista et al. (1962), so there is still a need for a reassessment of nomenclature following the excellent taxonomic account by Nag Raj (1977b). 
Description type:Non-original description 
Description:YPSILONIA Lév., Ann. Sci. nat., ser. 5, 3: 284 (1846).
Acanthothecium Speg., Boln. Acad. Nac. Cienc. Cordoba 11: 228 (1889).
Psalidosperma Syd., Annls mycol. 12: 571 (1914).
Sp. typ.: T. cuspidata Lév.
Illustrations: Nag Raj (1977b).
Mycelium superficial, dark brown, septate, radiating often in adpressed strands from the centre. Conidiomata superficial, amphigenous, separate, rarely aggregated, dark brown, sessile, at first globose and closed, later opening to become cupulate, situated on a flat, effuse stroma composed of dark brown, thick-walled textura angularis; periclinal wall composed of textura angularis towards the inside and textura intricata eventually extending into setae on the outside. Ostiole absent. Setae restricted to periclinal wall, incurved over the conidiogenous region, later becoming divergent, acuminate, apex obtuse or acute, septate, thick-walled, dark brown. Conidiophores pale brown, branched at the base, septate, smooth, cylindrical, formed mainly from the base. Conidiogenous cells holoblastic, integrated or discrete, pale brown, smooth, cylindrical. Conidia formed singly from the apex of each conidiogenous cell, smooth, pale brown, consisting of 4 arms, the two upper ones tapered, divergent and 2-septate, the two lower ones parallel, one of which is longer, tapered and 3-4 septate, the other 2-3 septate, shorter, cylindrical with the truncate base indicating the point of secession from the conidiogenous cells.

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