Massaria De Not., G. bot. ital. 1(1): 333 (1844).
Saprobic on host. Sexual morph: Ascomata (pseudothecia) large, globose, subglobose, pyriform to strongly depressed; immersed in bark and sometimes the outermost wood layer, scattered or grouped and typically firmly embedded in pseudostromatic tissues intermixed with substrate cells, forming pallid areas around ascomata, often surrounded by blackened marginal zones, and often also covered by a dark clypeus. Ostioles central or excentric, short or long, solitary or converging in groups, projecting through the bark, greyish, whitish, rosy or yellow in median vertical section. Apex erumpent, stout papillate, rounded with rounded pore, at times surmounted by peaks of stromatic tissues that form coarsely sulcate tips above the bark surface. Pseudothecial wall wide, firm, opaque, composed of numerous rows of thin-walled, inhomogeneously pigmented, compressed angular cells up to 25 μm long, darkly pigmented externally, paler toward interior; surface smooth. Hamathecium of numerous persistent, indistinctly septate, branching and anastomosing trabeculae. Asci bitunicate, fissitunicate, basal and peripheral, oblong, cylindrical or fusoid, less commonly saccate, with thin ecto- and thick endotunica, apically with wide ocular chamber and refractive ring, containing four, six or eight uni-, bi- or triseriate ascospores. Ascospores large, oblong, cylindrical, ellipsoidal or fusoid, rounded or tapered to subacute ends, hyaline, light to dark brown, after ejection always brown, straight or slightly inequilateral, symmetric, biconoid and symmetrically 1-euseptate in early stages, not or slightly constricted, secondary septa usually closer to primary septum than to ends of ascospore; wall thick, smooth, surrounded by gel coating; lumina rhomboid or lenticular in mid cells, conoid in end cells. Asexual morph: Unknown (Adapted from Voglmayr & Jaklitsch, 2011).
Type species: Massaria inquinans (Tode) De Not.
Notes: Massaria was introduced by De Notaris (1844) based on Sphaeria inquinans Tode (1791). Massaria is characterized by large, globose, subglobose ascomata, central or excentric ostioles, pseudothecial wall comprising compressed angular cells, cylindrical or fusoid asci and large, oblong, cylindrical, ellipsoidal or fusoid ascospores. Shoemaker and LeClair (1975) and Barr (1979) transferred and described several Massaria species with brown, septate ascospores surrounded by a gelatinous sheath making the genus morphologically heterogeneous. Shoemaker and LeClair (1975) accepted only few species in Massaria characterized by large, symmetric, four-celled ascospores surrounded by a massive gelatinous sheath. The study of Shoemaker and LeClair (1975) gave rise to detailed morphological descriptions of Massaria from authentic and type collections but they did not provide a key for identification. Barr (1979, 1990) discussed the separation of Aglaospora from Massaria based on grouped pseudothecia surrounded by stromatic tissues and ascospores characters while Petrak (1921) could not differentiate between these genera. The study of Barr (1979, 1990) resulted in some inconsistencies between her descriptions and original species concepts as she studied only North American specimens and did not examine the types of European species. The species concepts of Barr (1979) were followed by consequent authors (Treigienė & Rukšėnienė, 2005). Barr (1990) accommodated Massaria in Massariaceae based on morphology mainly large, brown, septate ascospores together with some other genera which was previously in Melanommatales (Barr, 1990) or Pyrenulales (Eriksson, 1981). Schoch et al. (2006) incorporated only Massaria platani in his phylogenetic analysis but the latter was not congeneric with the generic type Massaria inquinans and was transferred to Splanchnonema as Splanchnonema platani. Zhang et al. (2009) used M. inquinans and M. anomia in their multi-gene analyses and reported that two species were not congeneric as they formed different clades within the Pleosporales and re-introduced Aglaospora for M. anomia. Voglmayr and Jaklitsch (2011) carried a taxonomic revision of Massaria and introduced 17 new Massaria species based on morphology and multi-gene phylogeny based on LSU, SSU, RPB2 and TEF1. Voglmayr and Jaklitsch (2011) formally added Massarina macra in Massaria. The authors synonymized Aglaospora with Massaria and lecto- and epitypified the generic type Massaria inquinans They also showed Massaria vomitoria, M. gigaspora and M. pyri, previously considered as conspecific with M. inquinans, to be distinct species and introduced the new name M. gigaspora. Massaria has two different modes of ascospores germination in culture which is hyphal and form hyphal colonies or by ejection of a naked protoplast which forms meristematically growing colonies. Massaria is morphologically and phylogenetically a distinct genus in Massariaceae.