Portal:Sharks/Did you know/10

... that the Portuguese dogfish is the deepest-living shark known, found as far down as 3,675 m (2.284 mi)?
... that the single known specimen of the Irrawaddy river shark was generally dismissed as an abnormal bull shark until 2005?
... that the green lanternshark often preys on squid and octopus much larger than itself, which it may overwhelm by attacking in packs?
... that the barbeled houndshark is the only shark with a spherical placenta?
... that the cookiecutter shark may use the absence of bioluminescence to attract prey?