The Rabbit Sapsucking Slug, scientifically known as Costasiella usagi, is a species of sea slug belonging to the family Costasiellidae. This charming creature, often described as “bunny-like”, is a fascinating example of marine biodiversity.
Description & Characteristics
Costasiella usagi is a small, vibrant sea slug, reaching a maximum size of only 5 mm. Its most striking feature is its distinctive “rabbit” appearance. The slug’s bright green body is adorned with two long, pointed “ears” that resemble the ears of a rabbit. These “ears” are actually cerata, finger-like projections that contain the slug’s digestive and respiratory systems.
Habitat and Occurrence
The Rabbit Sapsucking Slug is predominantly found in the intertidal zone of the Indo-Pacific region. This marine zone experiences fluctuations in water levels, marking the transition between land and sea. The species’ presence in this zone indicates its ability to adapt to changes in salinity and water flow. It’s often encountered in shallow, rocky areas, where it can forage for its primary food source.
Taxonomy
The species Costasiella usagi belongs to the Class: Gastropoda, Family: Costasiellidae. Within the Class Gastropoda, the sea slug is a member of the highly diverse group of molluscs that includes snails and slugs. The Family Costasiellidae is a family of sea slugs, which are specifically known for their bright colors and feeding habits.
Feeding
The Rabbit Sapsucking Slug is a specialist feeder, primarily relying on a specific type of algae known as Vaucheria for sustenance. This unique dietary preference is reflected in the slug’s bright green color, which is derived from chlorophyll, a pigment found in Vaucheria. The sea slug utilizes its radula, a tongue-like structure, to scrape algae off rocks and ingest it.
Image References