corticolous

Corticolous describes organisms that dwell on the bark of trees. The term derives from Latin cortex meaning bark and the suffix -colous meaning dwelling on. In biology and ecology, corticolous is used especially for lichens and bryophytes, though other organisms that live on bark can be described as corticolous.

Many corticolous organisms occupy the surface of tree bark, including crustose, foliose, and fruticose lichens as well as mosses and liverworts. They may colonize living trees as well as dead standing trees (snags) and can show preferences for particular tree species, bark textures, or chemical characteristics such as pH and secondary metabolites. Bark roughness, moisture availability, light exposure, and microclimate on the trunk influence colonization and community composition. Corticolous lichens are often more abundant and diverse in humid, shaded forests, whereas bark characteristics in drier, exposed environments favor a different assemblage.

Ecologically, corticolous communities contribute to nutrient cycling, provide microhabitats for invertebrates, and can be indicators of air quality and forest health. They are frequently used in ecological and biogeographical studies and in biomonitoring.

Related terms include saxicolous (growing on rocks) and lignicolous (on wood). Etymology: cortex “bark,” -colous “dwelling on.”