Temporal range: Upper Cretaceous–Recent 
|Spiny dogfish, Squalus acanthias|
Squalidae, also called dogfish sharks or spiny dogfishes, are a family of sharks in the order Squaliformes. They have two dorsal fins, each with smooth spines, but no anal fin, and their skin is generally rough to the touch. Unlike virtually all other shark species, dogfish sharks possess venom which coats their dorsal spines – this venom is mildly toxic to humans.
They are carnivorous, principally preying upon organisms smaller than themselves.
- Froese, Rainer, and Daniel Pauly, eds. (2011). "Squalidae" in FishBase. February 2011 version.