48. * Diderma gracile Aramb., Bol. Soc. Argent. Bot. 15(2-3): 179 (1973)

Specimens examined. PERU. Ancash: Recuay, route AN-110, km 25, 42 km southeast of Chavín, 4060 m, 9º42′29”S, 77º17′48”W, 22 May 2014, leaves of Calamagrostis sp., Lado 23765 (MA-Fungi 95417, USM), Lado 23766 (MA-Fungi 95418, USM). Arequipa: Arequipa, Chiguata, route PE-34C, 31 km east of Chiguata, 4075 m, 16º23′18.1”S, 71º18′59.9”W, 10 Oct 2012, branch and leaves of Polylepis rugulosa, Lado 22330 (MA-Fungi 94859). Chiguata, route PE-34C, 31 km east of Chiguata, 4053 m, 16º23′35.6”S, 71º19′07.2”W, 10 Oct 2012, branch of Senecio sp., Lado 22336 (MA-Fungi 91218), Lado 22337 (MA-Fungi 94864), branches, leaves and bark of Polylepis rugulosa, Lado 22339a (MA-Fungi 94866). Chiguata, El Symbral, 4259 m, 16°23′26”S, 71°19′03”W, 15 May 2017, on leaf litter of Baccharis tricuneata (prostrate stem), Treviño Myx 73 (MA-Fungi 97921, HSP). Ayacucho: Huamanga, Acocro, route PE-3S, km 452, towards Sachamamba Km 204, 4062 m, 13º25′25”S, 74º02′27”W, 21 Apr 2017, leaves of Festuca orthophylla, puna vegetation, Lado 24946 (MA-Fungi 96143). Chiara, route PE-3S, km 424, Abra Toccto, 4171 m, 13º20′59”S, 74º11′03”W, 21 Apr 2017, leaves of Festuca sp., Lado 24955 (MA-Fungi 96152), Lado 24956 (MA-Fungi 96153). Huancavelica: Angaraes, Lircay, route PE-26B, km 60, Lircay, 4001 m, 12º57′45”S, 74º44′22”W, 24 Apr 2017, leaves of grasses, Lado 25156 (MA-Fungi 96344). Junin: Concepción, San José de Quero, route PE-24, km 212, Abra Negro Bueno, 4620 m, 12º08′36”S, 75º37′05”W, 28 Apr 2017, leaves of grasses, Lado 25475 (MA-Fungi 96628). Yauli, Santa Bárbara de Carhuacayan, near the junction to Chuqui, route PE-20A, km 183, 4418 m, 11º08′49”S, 76º25′55”W, 21 May 2018, grasses (Festuca sp.), Lado 27157 (MA-Fungi 97905), Lado 27158 (MA-Fungi 97906).

Notes. Similar to Diderma subasteroides M.L. Farr, but in this species, the peridium layers remain attached after dehiscence while the layers are separated even before the spore release in D. gracile (Arambarri 1973). It also may be confused with Diderma stellulum M.L. Farr, but the latter has a flattened columella. These records considerably enlarge the known distribution of the species in the southern hemisphere, previously only reported from Austral Argentina (Wrigley de Basanta et al. 2010).