Yellow Umbrella Slug

Tylodina perversa

This species, known as the Yellow Umbrella Slug, has a distinctive limpet-like shell primarily composed of protein rather than calcium carbonate. Its coloration is typically yellow, which helps divers identify it among other similar species. The Yellow Umbrella Slug can be found in the northeastern Atlantic, particularly around the British Isles and the Mediterranean Sea, inhabiting shallow waters. It is often located in depths shallower than 40 meters, with most sightings occurring under 20 meters. This species thrives in environments rich in sponges, which serve as its primary food source, specifically the sponge Aplysina aerophoba. The Yellow Umbrella Slug is known to be a hermaphrodite, allowing it to reproduce with any other individual it encounters. This reproductive strategy is common among members of the order Notaspidea, enhancing their chances of successful mating in their natural habitat. Divers may encounter this slug while exploring rocky reefs or sponge gardens, where it may be seen grazing on sponges or resting on the substrate. In terms of conservation status, the Yellow Umbrella Slug has not been evaluated by the IUCN. However, it is generally considered harmless to humans and does not have significant threats from human activities. Observing this species can be a unique experience for divers, as they often blend into their surroundings, making them an interesting find during dives.