Family: LAMNIDAE, Mackerel Sharks, Mako Sharks
conical snout
FAMILY LAMNIDAE
MACKEREL SHARKS, MAKO SHARKS
Lamnids are generally large (to 6 m), powerful sharks distinguished by a spindle-shaped body; pointed snout; teeth few, sharp, dagger-like or triangular and serrated, with 1 point; five long gill slits, all in front of pectoral fin; two dorsal fins, 1st well in front of pelvic fins; second dorsal and anal fins very small; tail base slender, strongly depressed, with large keels that extend well onto tail fin; tail fin lunate, almost symmetrical.
Mackerel sharks are partly warm-blooded, and have a circulatory system that enables them to retain a body temperature that is warmer than the surrounding sea. Development of the young is internal, without a yolk-sac placenta. They exhibit a remarkable phenomenon known as oophagy in which developing fetuses feed on fertilized eggs and possibly smaller siblings within the uterus. These rapid swimmers are capable of spectacular leaps when chasing their prey. They feed on a variety of fishes, other sharks, rays, sea birds, turtles, marine mammals, squids, and benthic crustaceans. They are aggressive, dangerous sharks that are sometimes responsible for fatal attacks on swimmers and surfers. The great white shark (Carcharodon carcharias) ranges into the northern and southernmost portions of our region, although its main distribution lies in cooler seas.
This family is distributed in all temperate and tropical seas. It contains three genera and five species, including the notorious Great White Shark. Two genera and 3 species occur in the tropical eastern Pacific.