First record of Harpellales, Orphellales (Kickxellomycotina) and Amoebidiales (Mesomycetozoea) from Bulgaria, including a new species of Glotzia Author Valle, Laia Guardia Unitat de Botanica, Dept. Biologia Animal, Biologia Vegetal i d'Ecologia. Fac. Biociences. Universitat Autonoma de Barcelona. 08193 - Bellaterra (Barcelona), Spain https://orcid.org/0000-0001-8295-1093 laia.guardia@uab.cat Author Stoianova, Desislava Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences. Sofia, Bulgaria https://orcid.org/0000-0001-8040-7158 text MycoKeys 2020 67 55 80 http://dx.doi.org/10.3897/mycokeys.67.52055 journal article http://dx.doi.org/10.3897/mycokeys.67.52055 1314-4049-67-55 CE9642BF68865BC2B7929C4F7076DCAE Genistellospora homothallica Lichtw, 1972. Figs 1 , 2 Specimens examined. Site 2: slides BUL-2-1, BUL-2-6, BUL-2-7 (zygo.), BUL-2-10; Site 3: slides BUL-3-1; site 4: slides BUL-4-10; Site 7: slides BUL-7-1, BUL-7-2, BUL-7-3; site 8: slides BUL-8-3; site 12: slide BUL-12-5. Notes. Genistellospora homothallica is a cosmopolitan species and its Simuliidae hosts are widespread and common in varied environments ( Lichtwardt et al. 2001 ), especially in fast flowing waters. This species has been previously documented from many countries in the Northern Hemisphere, including USA ( Lichtwardt 1972 ), Canada ( Moss and Lichtwardt 1976 ), United Kingdom ( Lichtwardt 1986 ), Spain ( Santamaria and Girbal 1998 ), France ( Valle 2004 ), Italy ( Valle et al. 2013 ) and Portugal ( Valle 2013a ). The species has also been recorded from Southern tropical regions, including Costa Rica ( Lichtwardt 1997 ), Puerto Rico ( White et al. 2000 ), Argentina ( Lopez-Lastra et al. 2005 ), Dominican Republic ( Valle and Cafaro 2010 ), Chile ( Lichtwardt and Arenas 1996 ) and Colombia ( Baron and Valle 2018 ). Trichospores of G. homothallica are typically ovate-elongated, slightly asymmetrical, measuring 34-40 x 10.5-12 μm in our collections. Young zygospores were observed in one Bulgarian specimen (BUL-2-7) with the characteristic zygosporophore of the species, bearing a straight or reflexed thumb-like terminal cell measuring 43-58 μm length. Often, G. homothallica thalli were covered with thalli of the epithallic Simuliomyces microsporus Lichtw., as seen in Fig. 2 (arrows). Figures 1, 2. Genistellospora homothallica and Simuliomyces microsporus from Simuliidae larvae. 1 Fertile branches of G. homothallica with terminal trichospores 2 fertile branches and trichospores of G. homothallica with an attached thallus of S. microsporus showing a trichospore (arrow) and conjugation tubes (arrowhead). Scale bars: 25 μm in all figures.