Codium Étalé

Overview

Codium effusum is an encrusting green alga characterized by its dull, olive-green appearance and a texture resembling thick felt or duvet. It forms compact, boursouflé (puffed) patches that adhere strongly to rocky substrates in marine environments.

Distribution & habitat

This species is found in the Mediterranean Sea and the Northeast Atlantic, including the coasts of Portugal, Madeira, and the Canary Islands. It has also been reported in various other regions, such as parts of the Indian Ocean, Australia, and Tasmania. It typically inhabits rocky areas and the base of seagrass beds, often favoring shaded environments.

Appearance

The thallus of Codium effusum grows as an encrusting plaque, generally reaching 5 to 15 cm in width and up to 1 cm in thickness. Its surface has a characteristic soft, felt-like quality and a matte olive-green color. It is distinguished from similar species by its strong adherence to the rock and its specific growth form, which is less mounded or convoluted than other related Codium species.