''Tetronarce'' is a
genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
of
rays, commonly known as electric rays. They are slow-moving
bottom-dwellers capable of generating
electricity
Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwel ...
as a defense and feeding mechanism. ''Tetronarce''
species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
tend to attain a much larger
size
Size in general is the Magnitude (mathematics), magnitude or dimensions of a thing. More specifically, ''geometrical size'' (or ''spatial size'') can refer to three geometrical measures: length, area, or volume. Length can be generalized ...
(up to 180 cm
TL) than ''
Torpedo
A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, such ...
'' species, which are usually small to moderate sized (range from 25 to 80 cm
TL) electric rays.
[
]
Species
There are currently nine recognized species in this genus:[Carvalho, M.R. de. (2015): Torpedinidae. In : Heemstra, P.C., Heemstra, E. & Ebert, D.A. (Eds.), Coastal Fishes of the Western Indian Ocean. ''Vol. 1. South African Institute for Aquatic Biodiversity, Grahamstown, South Africa. In press.'']
References
Fish of Argentina
Fish of Japan
Fish of Taiwan
Ray genera
Taxa named by Theodore Gill
{{Rajiformes-stub