ascolichen
Ascolichen is a term used to describe lichens that belong to the Ascomycetes fungal division. This division represents the largest phylum of the Fungi kingdom, and a significant majority of lichen-forming fungi fall within this group. Ascolichens are characterized by the presence of an ascocarp, which is the fruiting body of the ascomycete fungus, where ascospores are produced. These ascocarps can take various forms, such as apothecia (cup-shaped or disc-shaped) or perithecia (flask-shaped). The fungal partner in a lichen is called the mycobiont, and in the case of ascolichens, this mycobiont is an ascomycete. The other partner is usually a photosynthetic organism, the photobiont, which is typically an alga or a cyanobacterium. Together, the mycobiont and photobiont form the lichen thallus, the vegetative body of the lichen. The diversity of ascolichens is vast, encompassing a wide range of growth forms, from crusty to leafy to shrubby, and they inhabit a multitude of environments globally, from polar regions to deserts and tropical rainforests. Their ecological roles are important, contributing to soil formation, nutrient cycling, and providing habitat for other organisms. The classification of lichens is primarily based on the characteristics of the fungal partner, making the distinction of ascolichens significant in lichenology.