Chaline À Cheminées Roses

Overview

Haliclona viscosa is a marine sponge characterized by its variable growth form, often appearing as a spreading cushion or a massive, lobose structure. It is most easily recognized by its distinctive, volcano-like oscular chimneys, which are frequently arranged in irregular rows or ridges across its surface.

Distribution & habitat

This species is found in the Northeast Atlantic, the English Channel, and the Mediterranean. It typically inhabits rocky substrates, favoring vertical rock faces in areas with significant water movement and low turbidity. While most common in the infralittoral zone, it can be found from the shore down to depths of approximately 50 meters.

Appearance

The sponge is generally firm yet friable and is notably slimy to the touch, especially when handled or damaged. Its surface is smooth and punctate, marked by numerous small inhalant pores. While typically purple, individuals can also appear pink, brown, or greyish-purple, with the color often intensifying on the oscular chimneys. Large specimens can reach up to 30–40 cm in width and 5 cm in height.

Biology & behavior

Like other sponges, Haliclona viscosa is a sessile filter feeder. It draws in water through its surface pores and expels it through its prominent oscules, capturing microparticles such as bacteria, unicellular algae, and organic debris. The water flow is maintained by specialized ciliated cells known as choanocytes. The species is known to contain various chemical compounds, including 3-alkyl pyridine alkaloids, which may play a role in its ecological interactions.