The Pacific electric ray (Torpedo californica) is a
species of electric ray in the family Torpedinidae, endemic to the coastal
waters of the northeastern Pacific Ocean from Baja
California to British
Columbia . The electric ray, also called torpedo,
torpedo fish, numbfish, or crampfish, any of the rays of the families
Torpedinidae, Narkidae, Narcinidae, and Hypnidae, named for their ability to
produce electrical shocks. It generally inhabits sandy flats, rocky reefs, and kelp
forests from the surface to a depth of 200 m (660 ft), but has also been known
to make forays into the open ocean.
Measuring up to 1.4 m (4.6 ft) long, the Pacific
electric ray has smooth-rimmed spiracles (paired respiratory openings behind
the eyes) and a dark gray, slate, or brown dorsal coloration, sometimes with
dark spots. Its body form is typical of the genus, with a rounded pectoral fin
disc wider than long and a thick tail bearing two dorsal fins of unequal size
and a well-developed caudal fin.
These large flattened rays often lie partially buried
on sandy seafloors, where they use a specialized sensory system to detect the
electrical stimuli of potential prey and then attack them by ambush. The
predator wraps its body around a halibut or mackerel and uses special
kidney-shaped organs to produce a stunning electric charge of up to 50 volts.
The only electric ray found off western North America,
the Pacific electric ray occurs as far south as Sebastian Vizcaino Bay in Baja
California, and as far north as the Dixon Entrance in northern British
Columbia. It is most common south of Point
Conception , California ,
with the rays north of the Point perhaps representing one or more separate
populations.
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