Sharks and their relatives, including skates, rays, and chimaeras, are collectively termed chondrichthyan fishes (class Chondrichthyes). The skates and rays are known as batoids (superorder Batoidea) while the batoids and sharks together comprise the elasmobranchs (subclass Elasmobranchii).
The chondrichthyans are a relatively small (~1,150 described species), evolutionarily conservative group that has functioned successfully in diverse marine and aquatic ecosystems for over 400 million years. Despite their evolutionary success, many species are increasingly threatened with overexploitation as a result of their life history traits and the activities of humans.
|Place of Publication||Vancouver, Canada|
|Publisher||IUCN Species Survival Commission Shark Specialist Group|
|Number of pages||148|
|Publication status||Published - 2012|