Lesser electric ray

Lesser electric ray
Conservation status
Critically Endangered (IUCN 3.1) [1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Chondrichthyes
Order:	Torpediniformes
Family:	Narcinidae
Genus:	Narcine
Species:	N. bancroftii
Binomial name
Narcine bancroftii (E. Griffith & C. H. Smith, 1834)

The lesser electric ray (Narcine bancroftii), also known as the Brazilian electric ray, small electric ray, spotted torpedo ray, torpedofish or trembler,^[2] is a species of numbfish in the family Narcinidae.^[2]

Description

This species of ray has a near-circular^[3] body and a short tail. It grows to approximately 45 centimeters (18 in) long, and 20 cm (8 in) wide,^[3] with colouration ranging from dark brown to reddish orange. It has irregular rings, sometimes oval in shape. The ventral surface ranges from white to greenish. It has tooth rows that vary in number from 17 to 34 in each jaw. This depends on the size of the specimen.^[2]

It has two electric organs, elongate in shape, that run from the front of the eyes, down to the rear end of the disc. These organs can generate a peak voltage of about 14 to 37 volts, which they use to stun prey, and to defend themselves.^[2]

Distribution

This species is found in the Gulf of Mexico, and in the coastal waters of the western Atlantic Ocean from northeastern Brazil to North Carolina. It is also common in the Caribbean Sea and the West Indies.^[3]

Habitat

The lesser electric ray is most commonly found under sand or mud, in intertidal shallow waters, but has been found at depths of up to 180 feet (55 m).^[2]

Behavior

This specis is nocturnal. It remains motionless during the daytime, and forages for food in the substrate at night.^[3]

Diet

Lesser electric rays feed mainly on polychaete annelids. They also eat juvenile snake eels, sea anemones, small bony fish and various crustaceans.^[2]

References

1. ^ "Narcine bancroftii". IUCN Red List of Threatened Species. Version 3.1. International Union for Conservation of Nature. 2007. http://www.iucnredlist.org/apps/redlist/details/63142. Retrieved April 13, 2011. 
2. ^ ^{a b c d e f} Michelle Press. "Lesser electric ray". Florida Museum of Natural History. http://www.flmnh.ufl.edu/fish/gallery/descript/lesserelectricray/lesserelectricray.html. Retrieved February 16, 2011. 
3. ^ ^{a b c d} "Lesser electric ray". Elasmo Field Guide. elasmodiver.com. http://www.elasmodiver.com/lesser_electric_ray.htm. Retrieved February 16, 2011. 

External links

• Range map
• Image showing teeth