Dictyote Spatulée

Overview

Dictyota spiralis is a species of brown alga found in the temperate eastern Atlantic Ocean, the Mediterranean Sea, and the Black Sea. It is typically observed from spring through autumn, often disappearing during the winter months.

Distribution & habitat

This species is found in the Mediterranean, the Black Sea, and the eastern Atlantic, ranging from the British Isles down to the Canary Islands and Mauritania. It prefers shallow, well-lit rocky substrates in calm water conditions, often growing on rocky platforms or sandy bottoms.

Appearance

This alga features an erect, membranous thallus that is yellowish-brown in color, sometimes displaying greenish, iridescent tips. It grows in clumps of flattened, ribbon-like fronds that lack a midrib. The fronds are generally 3 to 4 mm wide and can reach a maximum height of 15 cm. The branching pattern is pseudodichotomous, with relatively few divisions, and the tips are often rounded or spathulate in shape. It is anchored to the seabed by stolons.

Reproduction

Dictyota spiralis is a dioecious species, meaning male and female reproductive organs are found on separate individuals. Reproduction occurs from spring to summer. During this process, gametes are grouped into structures called sori, which appear as dark patches on the thallus before the spores are released.