Gregarithecium Kaz. Tanaka & K. Hiray., Stud. Mycol. 82: 88 (2015).
MycoBank number: MB 811298; Index Fungorum number: IF 811298; Facesoffungi number: FoF 08213; 1 morphological species (Species Fungorum 2020), 1 species with molecular data.
Type species – Gregarithecium curvisporum Kaz. Tanaka & K. Hiray., Stud. Mycol. 82: 88 (2015).
Notes – Gregarithecium belongs to family Dictyosporiaceae, and was introduced by Tanaka et al. (2015). Members of this genus have immersed to erumpent, depressed globose to hemisphaerical ascomata with flattened base, fissitunicate 8-spored asci and hyaline broadly fusiform ascospores with a median septum, surrounded by an entire sheath. Gregarithecium is reminiscent of species in Massarina sensu lato (Aptroot 1998, Tanaka & Harada 2003d. However, Gregarithecium can be distinguished from Massarina sensu lato by stromatic tissue surrounding the ascomata.