Amblyraja

Amblyraja is a genus of skates in the family Rajidae. They are found in the northeastern Atlantic Ocean and the northwestern Pacific Ocean. Members of the genus are commonly called smooth skates.

Starry ray – Amblyraja radiata

Southern thorny skate – Amblyraja doellojuradoi

Description

Amblyraja skates are characterized by their smooth, scaleless skin, a long, slender snout, and relatively large pectoral fins that extend beyond the head. They have a distinctive pattern of dark spots or blotches on their dorsal surface. The pelvic fins are small and rounded. Their tails are slender and whip-like, with a single dorsal fin and a pair of small, widely separated ventral fins.

Habitat and Distribution

Amblyraja skates inhabit a variety of marine environments, from shallow coastal waters to deep sea bottoms. They are commonly found on sandy or muddy substrates, and can tolerate a wide range of temperatures and salinities. The genus is distributed throughout the northeastern Atlantic Ocean, including the North Sea, the Baltic Sea, and the Mediterranean Sea. They are also found in the northwestern Pacific Ocean, from Japan to Alaska.

Diet and Ecology

Amblyraja skates are opportunistic feeders, preying on a variety of small invertebrates, including crustaceans, mollusks, and worms. They also feed on small fish, such as herring and cod. They locate their prey using their keen sense of smell and touch, and capture it with their sharp, pointed teeth.

Reproduction

Amblyraja skates are ovoviviparous, meaning that the embryos develop inside eggs that are retained within the mother's body. The embryos are nourished by a yolk sac, and are born live. Females can produce multiple litters of young per year, with the number of pups ranging from one to eight depending on the species.

Species

The following species are recognized in the genus Amblyraja:

  • Amblyraja badia
  • Amblyraja georgiana
  • Amblyraja hyperborea
  • Amblyraja jenseni
  • Amblyraja kvitkiana
  • Amblyraja radiata
  • Amblyraja rostrata
  • Amblyraja stephanus
  • Amblyraja sublaevis

Conservation Status

Several species of Amblyraja are considered to be threatened or endangered, due to factors such as overfishing, habitat degradation, and climate change.

References

  • Compagno, L. J. V. (2001). Sharks of the world. An annotated and illustrated catalogue of shark species known to date. 2. Bullhead, mackerel, and carpet sharks (Heterodontiformes, Lamniformes and Orectolobiformes). FAO Species Catalogue for Fishery Purposes, 1, 1–269.
  • Froese, R. and Pauly, D. (Eds.). (2023). FishBase. World Wide Web electronic publication. Available at: https://www.fishbase.org (accessed 2023-03-18).
  • IUCN Red List of Threatened Species. Available at: https://www.iucnredlist.org (accessed 2023-03-18).