Six-Gill Sawsharks

About

Six-gill sawsharks belong to the genus Pliotrema and are distinguished by having six pairs of gill slits, unlike most other sharks that have five. Initially, only one species, Pliotrema warreni, was recognized, but in 2020, two new species, Pliotrema kajae and Pliotrema annae, were discovered off the coasts of Madagascar and Zanzibar. These sharks are part of the family Pristiophoridae and are known for their saw-like snouts used to hunt prey. Six-gill sawsharks are found in warm-temperate and subtropical waters, typically at depths of 37 to 500 meters. They are ovoviviparous, giving birth to litters of five to seven pups annually. Their diet includes small fish, crustaceans, and squid. Despite not being targeted commercially, they are often caught as bycatch. The discovery of new species highlights the richness of marine biodiversity and the need for better conservation efforts to protect these and other shark species.