Spotted Berthella

Berthella ocellata

Berthella ocellata is a sea slug characterized by its oval shape when moving and circular form when stationary. This species can reach an adult length of about 7 cm. It features a pair of small black eyes and a mouth located underneath, with a buccal veil on either side. The slug has tubular rhinophores positioned in front of the eyes and a yellow, bipinnate gill located on the right side at the back. Its body displays two distinct color forms: brown or whitish, both adorned with translucent tubercles surrounded by white rims. This species inhabits the eastern Atlantic Ocean and the Mediterranean Sea, typically found on rocks in the shallow sublittoral zone at depths less than 20 m, although it can occasionally be found as deep as 120 m. Being nocturnal, Berthella ocellata spends daylight hours hidden under stones, in crevices, or caves. Its diet consists mainly of sponges, which it feeds on using a muscular radula to scrape off fragments. Berthella ocellata is hermaphroditic, with genital pores located on the right side in front of the gill. During mating, two slugs align themselves head to tail and exchange sperm. Fertilization occurs internally, and it is likely that eggs are laid in a gelatinous spiral, similar to other species in its genus. Encounters with this species during dives may involve observing them in their natural habitat, often camouflaged among rocks and sponges.