Pseudomicrothecium Y. Marin , Stchigel, Guarro, Cano, gen. nov.

Marin-Felix, Yasmina, Guarro, Josep, ano-Lira, Jose F., Garcia, Dania, iller, Andrew N. & Stchigel, Alberto M., 2018, Melanospora (Sordariomycetes, Ascomycota) and its relatives, MycoKeys 44, pp. 81-122 : 81

Pseudomicrothecium Y. Marin, Stchigel, Guarro, Cano, gen. nov.

Type species.

Pseudomicrothecium subterraneum (L. Fan, C.L. Hou, P.F. Cannon & Yong Li) Y. Marín, Stchigel, Guarro & Cano. Holotype and ex-isotype strain: BJTC FAN1001, K[M] 172128.

Description.

Ascomata non-ostiolate, globose, translucent, pale brown to brown, appearing dark brown when the ascospores are mature, glabrous or setose; ascomatal wall membranaceous, of textura angularis. Asci 2-spored, clavate, short-stipitate, without apical structures, evanescent. Ascospores one-celled, at first hyaline, becoming dark brown to blackish when mature, ellipsoidal to citriform, umbonate and truncate at both ends, with a terminal indistinct germ pore at each end. Asexual morph absent.

Etymology.

The name refers to the morphological resemblance to Microthecium .

Notes.

The new genus Pseudomicrothecium is proposed here to accommodate Melanospora subterranea because it constitutes a separate lineage in our phylogenetic study. This genus is characterized by its non-ostiolate ascomata, similar to those of Microthecium , 2-spored asci and smooth-walled ascospores with an indistinct germ pore at each end. Asci containing two ascospores have only been observed in some species of Scopinella (i.e. Scopinella gallicola and S. sphaerophila ). However, Scopinella can be easily distinguished from Pseudomicrothecium by the production of ostiolate ascomata with long necks and cuboid-ellipsoidal ascospores with two prominent longitudinal germ slits.