Raja polystigma, commonly known as the Polka-dot skate, is a species of skate belonging to the family Rajidae. It is characterized by its distinctive spotted pattern and its relatively small size.
Description and Characteristics
Raja polystigma typically reaches a maximum size of 60.0 cm. Its body is flattened and disc-shaped, with a pointed snout and large pectoral fins that extend to the sides of its head. Its dorsal surface is covered in numerous dark spots or “polka dots” against a lighter background, giving it its common name. These spots are arranged in a scattered pattern and contribute to its camouflage in its preferred habitat.
Habitat and Occurrence
Raja polystigma is a deep-water species that prefers depths ranging from 100.0 to 400.0 meters. It is commonly found in the bathyal zone, which is characterized by its dim light and a lack of photosynthetic activity. The Polka-dot skate is typically found in the eastern North Atlantic Ocean, with a range extending from the Bay of Biscay to the Norwegian Sea. This distribution places it within the northeastern Atlantic marine ecoregion, where it contributes to the diverse marine life of the region.
Taxonomy
Raja polystigma belongs to the Class: Elasmobranchii, Order: Rajiformes, and Family: Rajidae. Elasmobranchii comprises cartilaginous fish, which includes sharks, rays, and skates. Rajiformes encompasses the order of skates and rays, characterized by their flattened bodies and broad pectoral fins. The Rajidae family, which includes the Raja polystigma, comprises a large and diverse group of skates that are found in oceans worldwide.
Feeding
Raja polystigma is a carnivorous fish, feeding primarily on benthic invertebrates such as crustaceans, worms, and molluscs. It uses its flattened body and sharp teeth to locate and capture prey on the seabed. Its diet plays an important role in maintaining the balance of the deep-sea ecosystem.
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