Rose De Mer

Overview

Pentapora foliacea, often known as the "Rose de mer," is the largest bryozoan species found in the Atlantic. It forms impressive, rigid, and brittle colonies that can reach significant sizes, often appearing as a complex, honeycomb-like mass of calcified plates.

Appearance

These colonies typically grow in a hemispherical or domed shape, characterized by wavy, convoluted sheets that branch out from an encrusting base. The structure is a deep orange or brownish-orange color, which may fade to a pale buff when the colony dies. When the tiny individual animals, or polypides, extend their feeding structures, the colony takes on a soft, velvety, or fuzzy appearance.

Distribution & habitat

This species is commonly found along the coasts of the British Isles, the English Channel, and the northeastern Atlantic. It prefers current-swept environments, typically attaching to bedrock or large boulders in areas often scoured by coarse sand or gravel.

Feeding

As a microphage filter feeder, the colony captures food particles from the water column. Each individual polypide extends a lophophore—a crown of ciliated tentacles—to trap plankton. A layer of mucus on these tentacles helps collect the particles, which are then transported to the mouth by the movement of fine cilia.