Didymium umbilicatum D. Wrigley, Lado & Estrada.

Didymium umbilicatum D. Wrigley, Lado & Estrada. [21, 1] Fig. 30 Loc. 2: On Prg bark, JRM252, 5 January 2009, (mc; pH = 7.2). Loc. 13: On Agl decayed, AET11694 (MA-Fungi 88114 sub Lado18841), AET11696 (MA-Fungi 88116 sub Lado18843), AET11698 (MA-Fungi 88117 sub Lado18845), AET11699 (MA-Fungi 88118 sub Lado18846), AET11700 (MA-Fungi 88119 sub Lado18847), AET11702 (MA-Fungi 88120 sub Lado18849), AET11704, AET11705, AET11708 (MA-Fungi 88121 sub Lado18855), 28 October 2007. Loc. 14: On Ags decayed, AET11745 (MA-Fungi 88138 sub Lado18892), AT11750, AET11751, AET11756 (MA-Fungi 88142 sub Lado18903), 28 October 2007. Loc. 15: On Y sp. leaves, AET11719, AET11734 (MA-Fungi 88134 sub Lado18881), 28 October 2007. Loc. 19: On Ags decayed, AET11894 (MA-Fungi 88199 sub Lado19041), 1 November 2007. Loc. 21: On Agl leaves, AET11865 (MA-Fungi 88188 sub Lado19012), AET11866 (MAFungi 88189 sub Lado19013), AET11868, AET11871 (MA-Fungi 88190 sub Lado19018), AET11878, 1 November 2007. This species is only known from Mexico, usually developed on species of Agave (Estrada-Torres et al. 2009). Unlike Didymium mexicanum, D. umbilicatum is common in the field, but not in moist chamber culture. Didymium umbilicatum has been considered a synonym of D. mexicanum (Moreno et al. 2012), but there are clear morphological differences that separate both species such as size, shape and morphology of the spores. There are no genetic or molecular studies that include both species to verify that they are of independent evolutionary lineages. A study on species delimitation is necessary to determine the taxonomic validity of Didyium umbilicatum.