The Black-tipped Spiny Dorid, scientifically known as Acanthodoris rhodoceras, is a fascinating species of sea slug belonging to the family Onchidorididae. This small, vibrant nudibranch is easily recognizable by its distinctive black-tipped cerata (finger-like projections) and its characteristic bright orange or red body.
Description & Characteristics
The Black-tipped Spiny Dorid, Acanthodoris rhodoceras, is a relatively small nudibranch, reaching a maximum size of about 25 mm. Its body is typically a vibrant orange or red color, often with white or yellow markings. The most prominent feature of this species is its black-tipped cerata, which are numerous and extend from the dorsal surface of the body. These cerata are believed to play a role in respiration and defense. The Acanthodoris rhodoceras also possesses a pair of rhinophores, sensory organs used to detect food and other stimuli, located on the top of its head.
Habitat and Occurrence
The Black-tipped Spiny Dorid, Acanthodoris rhodoceras, is found in a variety of marine environments, primarily in shallow, rocky areas. It is a common inhabitant of the intertidal zone, where it can be found clinging to rocks, seaweed, and other submerged surfaces. This species is also known to occur in subtidal habitats, particularly in areas with a good supply of its preferred food source. While it’s not specified, we can assume that the Acanthodoris rhodoceras can be found in both the neritic and oceanic zones, as its habitat is predominantly in coastal regions and shallow waters.
Taxonomy
The species Acanthodoris rhodoceras is a member of the Class: Gastropoda, Order: Nudibranchia, and Family: Onchidorididae. This family, Onchidorididae, encompasses a diverse array of sea slugs characterized by their generally small size, squat body shape, and the presence of cerata. The Nudibranchia, commonly known as sea slugs, are an order within the Gastropoda that lack shells and are notable for their often brilliant colors and diverse forms.
Feeding
The Black-tipped Spiny Dorid, Acanthodoris rhodoceras, is a carnivore and a specialist feeder, primarily feeding on bryozoans, also known as sea mats. Bryozoans are colonial animals that form intricate, often delicate, structures in a variety of marine habitats. The Acanthodoris rhodoceras uses its radula, a chitinous ribbon of teeth, to scrape and ingest these bryozoan colonies. The species’ preference for bryozoans is reflected in its distribution and abundance, as its populations tend to be concentrated in areas with high densities of bryozoans.
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