|Torpediniformes (Greek torpere-, 'be stiffed or paralyzed')
Taxonomy: Superclass: Gnathostomata- jawed fishes
Class: Chondrichtyes- cartilaginous fishes
Subclass: Elasmobranchii- rays, sharks and relatives
Superorder: Batoidea- rays and skates
Order: Torpediniformes- electric rays
Torpedinidae: electric rays
Hypnidae- coffin rays
Narkidae- sleeper rays Torpedo panthera
11 Genera: 69 species
They are characterized by their flattened enlarged pectoral fins and inflexible circular body with a distinct caudal fin. Their Jaws are extremely slender, no labial cartilages, rostrum is absent or reduced. The disc truncate or emarginate anteriorly. Other characteristics includes 0 to 2 dorsal fins, eyes are small (or in some obsolete in four species), skin are smooth that devoid of any apparent scales. Their large shaped-like electric organs located in the disc on each side of head is composed of columns of modified muscle; this allows them to send powerful shocks (up to 200 volts) that can stun their prey and discourage predator.
Bottom dwellers of ocean floor and bury under sand during the day and come out at night to feed.
Marine; temperate and tropical waters over a considerable depth range from intertidal waters to deep waters.
Ecology and life history:
Spend most of their time bury in sand and feed on many small invertebrates that includes mollusks, worms, and crustaceans. Like all rays, they have an ovoviviparous mode of reproduction, in which the female retain the developing egg internally and nourished by yolk. Very little is known about their life history.
The mediterranean species were used by the ancient Greeks and Romans as a form of electrotherapy to afflictions such as arthritis, headache and gout. They are not commercially important to humans as a food source, though occasionally they are encountered in their natural habitat by scuba divers. Because of their ability to generate electricity it can knock a human down; so precautions are needed to avoid being shock. Fossil records has showed that they first appeared in early tertiary age. Also, due to their immobility of burying in the sand most of the time, they are susceptible to trawl fisheries. The feeding behavior and kinematics of Narcine brasilensis, a lesser electric ray was studied because of their extreme and unique method of prey capture. Unlike other rays, they are a benthic suction feeder with a highly protrusible jaws (Dean and Philip 2004).
Dean, Mason N., and Philip J. Motta. "Feeding Behavior and Kinematics of the Lesser Electric Ray, Narcine Brasiliensis (Elasmobranchii: Batoidea)." Zoology 107.3 (2004): 171-89. Print.
Bond, Carl E. Biology of Fishes. Fort Worth: Saunders College Pub., 1996. Print.
"Family Details for Torpedinidae - Electric Rays." N.p., n.d. Web. 03 Feb. 2013. .
Bond, Carl E. Biology of Fishes. Philadelphia: W.B. Saunders, 1979. Print.