Squalus is a
genus of
dogfish sharks in the
familySqualidae. Commonly known as spurdogs, these
sharks are characterized by smooth
dorsal fin spines, teeth in upper and lower
jaws similar in size,
caudal peduncle with lateral keels; upper precaudal pit usually present, and
caudal fin without subterminal notch. In spurdogs, the hyomandibula (the bone connecting the braincase to the jaws) is oriented at a right angle to the
neurocranium, while in other sharks, the hyomandibula runs more parallel to the body. This led some to think that the upper jaw of Squalus would not be as protractile as the jaws of other sharks. However, a study that compared different jaw suspension types in sharks showed that this is not the case and that Squalus is quite capable of protruding its upper jaw during feeding.[5]
The name comes from squalus, the
Latin for shark; this word is the root for numerous words related to sharks such as squaline and
scientific names for sharks, such as the order
Squaliformes.
Species
Currently, 32 recognized species are placed in this genus:
^Wilga, C.D., Motta, P.J. & Sanford, C.P. (2007): Evolution and ecology of feeding in elasmobranchs. Integrative and Comparative Biology, 47 (1): 55-69.
^
abcdeViana, S.T.d.F., Carvalho, M.R.d. & Gomes, U.L. (2016): Taxonomy and morphology of species of the genus Squalus Linnaeus, 1758 from the Southwestern Atlantic Ocean (Chondrichthyes: Squaliformes: Squalidae). Zootaxa, 4133 (1): 1-89.