Saccothecium Fr., Fl. Scan.: 349 (1836).

Synonyms

Metasphaeria Sacc., Syll. fung. (Abellini) 2: 156 (1883)

Phaeodothiora Petr., Sydowia 2(1-6): 82 (1948)

Pleosphaerulina Pass., Atti R. Acad. Lincei, Rendiconti Cl. Sci. Fis., sér. 5 7(2): 46 (1891)

Schizostege Theiss., Annls mycol. 14(6): 415 (1917) [1916]

Parasitic or saprobic on woody branches and rarely on leaves in terrestrial habitats. Sexual state: Ascomata black, immersed to erumpent, solitary or gregarious, globose to subglobose, usually uniloculate, thick-walled, sometimes ostiolate. Peridium composed of several layers of brown to dark brown pseudoparenchymatous cells of textura angularis. Hamathecium lacking pseudoparaphyses. Asci 8-spored, bitunicate, fissitunicate, saccate to broad-clavate, becoming cylindric-clavate just before rupture, with a short bifurcate pedicel or apedicellate, apex broadly rounded with a distinct ocular chamber. Ascospores biseriate to triseriate, partially overlapping, hyaline, 3 to many septate, muriform to phragmosporous, obovoid or elliptic with broadly to narrowly rounded ends. Asexual state: aureobasidium-like; conidia hyaline or brownish, ovate, aseptate (Barr 1972).

Notes: Saccothecium was introduced by Fries (1836) and Kirschstein (1938, 1939) introduced several species which had been assigned to Metasphaeria, Sphaerulina, Leptosphaeria and Sphaeria. Kirschstein (1939, 1941) added two new species to Saccothecium, while Vassiljeva (2006) introduced Saccothecium cornicola Lar.N. Vassiljeva,. Pande (2008) placed several species in Saccothecium, which had been classified under Pringsheimia or Metasphaeria, but most are invalid (MycoBank 2014). Wehmeyer (1957) and Holm (1975) proposed to lectotypify the genus with Saccothecium sepincola. Froidevaux (1972) and Sivanesan (1984) synonymized Saccothecium sepincola under Pringsheimia sepincola and they considered P. sepincola as the type species of Pringsheimia. Saccothecium has been assigned to Dothioraceae, Dothideales (Barr 1972, 1987a and 2001; Kirk et al. 2008; Lumbsch and Huhndorf 2010) based on similar morphological characters of peridium, asci and ascospores (Barr 1972), while Pringsheimia is considered to be distinct from Saccothecium (Barr 1987a; 2001). Molecular phylogenetic analysis, Schoch et al. (2009) shows that Saccothecium sepincola (CBS 278.32) clustered within Didymellaceae and Zhang et al. (2012) included Saccothecium in Pleosporales genera incertae sedis. As there are no morphology-molecular link between the strain CBS 278.32 and S. sepincola it is difficult to show the affinities of Saccothecium in Pleosporales. However, we collected S. sepincola from Italy and directly isolated DNA from ascostromata. Our collection of S. sepincola from Italy clustered in Aureobasidiaceae in our phylogenetic analysis. Therefore, we assign Saccothecium in Aureobasidiaceae.

Type species: Saccothecium sepincola (Fr.) Fr. [as ‘saepincola’], Summa veg. Scand., Section Post. (Stockholm): 398 (1849).