Floristic study of lichens in Pashmin region of Ilam province

Lichens are symbiotic organisms from the community of a fungal part and an algal part. In this research, after taking samples from Pashmin mountains area of Malekshahi city of Ilam province, using tools such as magnifying glass, gardening shears, masonry pen, saw and some other tools, the samples were prepared for the next steps. To identify lichens, in addition to using different identification keys, chemical tests, thin layer chromatography (TLC) test and histological examination have also been used. In chemical tests, K, C, KC and PD tests have been performed. To investigate the histological structure of lichens, by performing different laboratory steps and using different compounds such as FAA solution, alcohol, combining alcohol with toluene, after fixing the samples in paraffin and molding, cutting the samples using a facial microtome. and after going through some steps, the final stabilization and preparation of images using a microscope has been done. After examining the study area, conducting sampling and various laboratory steps, and also using different identification keys, 27 species from 7 lichen families have been identified and introduced, of which 5 species have been identified for the first time in Ilam province. It has been reported. In these 7 families, Physciaceae, Megasporaceae and Acarasporaceae families have the most abundance in the lichen flora of the study area.