Mediterranean Bath Sponge Spongia officinalis adriatica
The Mediterranean bath sponge, as its name suggests, is collected and processed for use as a bath sponge. It grows as rounded cushions and mounds, and is usually dull gray to black outside but yellowish white inside. It can be used as a sponge because it has no sharp skeletal spicules, just a network of tough fibers made from an elastic material called spongin. Huge numbers were once harvested, but today they are rare.
- Class Demospongiae
- Width Up to 14 in (35 cm)
- Depth 3–165 ft (1–50 m)
- Habitat Rocks
- Distribution Mediterranean, especially the eastern part