Mésophylle Lichenoïde

Overview

Mesophyllum lichenoides is a small, calcified red alga characterized by its thin, brittle, and leafy appearance. It is commonly found in temperate Atlantic waters and parts of the Mediterranean, where it often grows on rocky substrates or as an epiphyte on other marine algae.

Appearance

This species forms flattened, semi-circular lobes that are typically less than 1 mm thick and measure 2–3 cm in diameter. The thallus is often concentrically banded and displays colors ranging from pale pink to dark purple, frequently featuring distinct white margins. When exposed to direct sunlight, the surface may bleach to a yellowish hue. Small, wart-like structures known as conceptacles are often visible on the surface of the lobes, particularly during reproductive periods.

Distribution & habitat

It is widely distributed across the Northeast Atlantic, ranging from the British Isles down to Mauritania, and is also present in the Mediterranean. It typically inhabits sheltered, shaded environments such as rock overhangs and tide pools. While it is often found attached to rocks, in the British Isles, it is frequently observed growing epiphytically on other algae like Corallina officinalis.

Reproduction

Reproduction occurs primarily during the winter and spring months. During this time, the species develops small, hemispherical conceptacles on the surface of its fronds to house reproductive cells. Once spores are released, these structures may leave behind small, persistent ring-like markings on the thallus.