Anthostomelloides Tibpromma & K.D. Hyde, gen. nov., Index Fungorum number: IF552117
Etymology: Anthostomelloides, resembling the genus Anthostomella
Saprobic on dead leaves of Pandanus odorifer (Forssk.) Kuntze. Sexual morph: Ascomata immersed, dark brownblack, globose, visible as conical blackened dots, ostioles present. Peridium composed of several layers, outwardly comprising brown cells of textura prismatica and inwardly comprising hyaline cells of textura prismatica. Hamathecium comprising numerous, filamentous, septate, tapering paraphyses. Asci 6–8-spored, unitunicate, cylindrical, short apedicellate, with a wedge-shaped, J+, apical ring. Ascospores uniseriate, inequilaterally oblong-ellipsoidal, initially yellowish brown, becoming dark brown at maturity, guttulate, with a conspicuous mucilaginous sheath, germ slit straight, less than the spore length. Asexual morph: Undetermined.
Type species: Anthostomelloides krabiensis Tibpromma & K.D. Hyde
Notes: We compared Anthostomelloides with Anthostomella and Brunneiperidium and found that our new genus can be differentiated by its immersed, globose ascomata and a peridium comprising cells of textura prismatica. In Anthostomella, ascomata are immersed or semiimmersed, with a periphysate ostiolar canal, sometimes with small cells or appendages at the ends of the ascospores, which have a basal, dwarf cell, sometimes surrounded by a mucilaginous sheath, with a straight or spiral germ slit or absence of germ slit. Brunneiperidium has semiimmersed ascomata with a peridium comprising cells of textura irregularis with ellipsoidal, brown ascospores and germ slit present or absent, if present straight and slightly curved at the edges with not full length (Daranagama et al., 2015). Anthostomelloides morphologically resembles the palm genera Fasciatispora K.D. Hyde and Nipicola K.D. Hyde in Xylariaceae, but Fasciatispora has ellipsoid, oval to rhomboid ascospores with a wide equatorial pallid band, while Nipicola possesses broadly cylindrical asci with an amyloid or nonamyloid subapical ring and black ascospores (Fröhlich and Hyde, 2000).