Lobaria lichen. Close-up of the lichen Lobaria virens growing on the bark of a sycamore tree. There are several brown cup-shaped apothecia visible on the body of the lichen. Lichens are a distinct type of organism composed of both fungal and algal cells in a symbiotic association. The brown apothecia, or fruiting bodies (spore producing structures) are formed by fungi. These spores can form into new fungal components. Lobaria sp. lichen are susceptible to air pollution, and thus are commonly found only in rural areas. They are, however, very resistant to extremes of heat and cold, and can survive in droughts. Magnification: x0.3 at 35mm size.