The numbray or spottail sleeper ray (''Narke dipterygia'') is a
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of
electric ray
The electric rays are a group of rays, flattened cartilaginous fish with enlarged pectoral fins, composing the order Torpediniformes . They are known for being capable of producing an electric discharge, ranging from 8 to 220 volts, depending ...
in the
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
Narkidae. It may be found in shallow muddy estuaries or offshore depths. It is a weak swimmer that lies on the bottom, commonly buried. It eats small marine invertebrates and fish. It pounces on its prey and wraps its body around its prey, killing or stunning it with electrical shocks.
It has been observed that Numbrays are not as common as other types of rays in the area around the Indian Ocean. This can be attributed to the relatively large doubling time for a population, reaching up to 18 years.
References
Momeninejad, Ali & Keivany, Yazdan & Sultan-Mohammadi, Vahid. (2014). First record of the numbray, Narke dipterygia (Bloch & Schneider, 1801) from Iran (Elasmobranchii: Narkidae). Iranian Journal of Ichthyology. 1. 298-301
Narkidae
Marine fauna of East Asia
Marine fauna of South Asia
Marine fish of Southeast Asia
Fish described in 1801
Strongly electric fish
{{chondrichthyes-stub