Polybranchia
Polybranchia is a genus of sacoglossan sea slugs, also known as “sap-sucking slugs”, in the family Plakobranchidae. These marine gastropods are characterized by their unique feeding habits, which involve siphoning the chloroplasts from algae and utilizing them for photosynthesis. This process, known as kleptoplasty, allows Polybranchia species to obtain energy from sunlight, supplementing their diet of algae.
Common Names
Polybranchia species are commonly known as "solar-powered slugs" or "kleptoplastic sea slugs" due to their ability to perform photosynthesis.
Characteristics
Polybranchia sea slugs are typically small, ranging in size from a few millimeters to a few centimeters. They possess a flattened body with a distinctive, often colorful pattern. The body is covered in cerata, finger-like projections that serve as respiratory organs and may also contain stinging nematocysts acquired from their prey.
Polybranchia species have a pair of rhinophores, sensory organs used to detect food and navigate their surroundings. Their digestive system is adapted for consuming algae and extracting chloroplasts, which are then incorporated into their own cells. This allows them to thrive in environments with limited food resources.
Environments
Polybranchia sea slugs are found in tropical and subtropical regions worldwide. They inhabit shallow coastal waters, often associated with seaweed beds, seagrass meadows, and coral reefs. These slugs prefer habitats with abundant algae, their primary food source.