Éponge Nid D’abeille

Overview

Phorbas fictitius is an encrusting marine sponge that typically grows as a thin sheet or cushion, reaching up to 15 mm in thickness and forming irregular patches that can span 30 cm across. It is a common inhabitant of rocky substrates, often found in areas with significant water movement or currents.

Appearance

This sponge is characterized by a smooth, slippery surface featuring distinct circular depressions that contain inhalant pore sieves. Its coloration is highly variable, ranging from grey and pale pink to vibrant orange or deep red, often depending on local light levels and water clarity. The oscules (exhalant openings) are generally inconspicuous but feature slightly raised, translucent rims. When disturbed or removed from the water, the sponge is notably compressible and its surface structures may contract.

Distribution & habitat

Phorbas fictitius is widely distributed throughout the Northeast Atlantic, ranging from the British Isles and France down to the Canary Islands, and is also found throughout the Mediterranean Sea. It is primarily an infralittoral species, frequently recorded on vertical rock faces, under stones, or in tide-swept gullies.

Biology & behavior

As a member of the family Hymedesmiidae, this species is believed to reproduce by releasing brooded larvae into the surrounding water column. It is a filter feeder, utilizing its specialized pore sieves to draw in water and extract nutrients. The intensity of its pigmentation often correlates with its environment; for instance, individuals in clearer, well-lit waters tend to exhibit brighter red hues compared to those in more turbid conditions.