The long-tailed river stingray or antenna ray (''Plesiotrygon iwamae'') 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 freshwater
stingray
Stingrays are a group of sea rays, which are cartilaginous fish related to sharks. They are classified in the suborder Myliobatoidei of the order Myliobatiformes and consist of eight families: Hexatrygonidae (sixgill stingray), Plesiobatidae ( ...
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 ...
Potamotrygonidae. It is found in the
Amazon basin
The Amazon basin is the part of South America drained by the Amazon River and its tributaries. The Amazon drainage basin covers an area of about , or about 35.5 percent of the South American continent. It is located in the countries of Bolivi ...
in South America, ranging from Ecuador to
Belém
Belém (; Portuguese for Bethlehem; initially called Nossa Senhora de Belém do Grão-Pará, in English Our Lady of Bethlehem of Great Pará) often called Belém of Pará, is a Brazilian city, capital and largest city of the state of Pará in t ...
.
It lives in the main channel of the
Amazon River
The Amazon River (, ; es, Río Amazonas, pt, Rio Amazonas) in South America is the largest river by discharge volume of water in the world, and the disputed longest river system in the world in comparison to the Nile.
The headwaters of t ...
and lower parts of its major tributaries.
Characteristic features are a very long filiform tail, reduced eyes, and a low number of pectoral-fin radials.
It resembles the
black-tailed antenna ray (''P. nana''),
[ but is larger at up to in disc width.][
Their prey includes ]worm
Worms are many different distantly related bilateral animals that typically have a long cylindrical tube-like body, no limbs, and no eyes (though not always).
Worms vary in size from microscopic to over in length for marine polychaete wor ...
s, crustacean
Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group ...
s, mollusk
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...
s, and small bottom fish (such as small catfish
Catfish (or catfishes; order Siluriformes or Nematognathi) are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the three largest species alive, ...
).[ They can detect electrical and chemical signals from prey in mud and sand.
The species was described in 1987 by Hugo P. Castello from Museu de Zoologia, ]University of São Paulo
The University of São Paulo ( pt, Universidade de São Paulo, USP) is a public university in the Brazilian state of São Paulo. It is the largest Brazilian public university and the country's most prestigious educational institution, the best ...
. Previously misidentified, or unidentified, specimens were then found in other museums.[
The fish is named in honor of the zoologist Satoko Iwama (d. 1987) of the Instituto de Botânica in São Paulo (Brazil).]
References
External links
Species Description of Plesiotrygon iwamae at www.shark-references.com
{{Taxonbar, from=Q2716251
Potamotrygonidae
Freshwater fish of Brazil
Freshwater fish of Ecuador
Fish of the Amazon basin
Taxa named by Hugo P. Castello
Fish described in 1987