lithophilous

Lithophilous is an ecological and botanical term used to describe organisms that live on rocks or rock surfaces rather than in soil or on organic substrates. The term derives from Greek lithos, stone, and philos, loving. It is commonly applied to lichens, bryophytes, and some vascular plants that are adapted to rocky habitats.

Lithophilous communities occur on cliff faces, rock outcrops, boulder fields, and even on man-made stone structures such as walls and monuments. These organisms endure high light intensity, desiccation, and nutrient-poor conditions by occupying microhabitats in cracks and crevices where moisture can collect. In lichens, the thallus adheres to rock surfaces, often aided by rhizines; bryophytes form mats anchored by rhizoids; lithophytic plants have shallow, spreading roots that exploit crevices.

In ecology and taxonomy, lithophilous is used to describe a substrate preference. It overlaps with related terms such as saxicolous (rock-dwelling) and lithophyte (rock-dwelling plant), though lithophilous is a broader descriptor that can apply to fungi, lichens, mosses, and vascular plants.