Plesiotrygon iwamae is a freshwater stingray, commonly known as the Antenna Ray, they are the only member of the genus Pleisotrygon. They belong to the family Potamotrygonidae and to the class Elasmobranchii, which is what sharks belong to. They get to about 22 inches in length, this does not include the tail. Their distributionis the upper to lower Amazon River basin, from Ecuador to Belém, Brazil, in the Napo, Solimões, Amazonas and Pará rivers. Antenna rays have smaller mouths than most other rays. Because of this, they feed on black worms, or tubifex worms. When young (under 10 inches) this species has trouble eating even the smallest night crawlers so blood worms would be better. Larger specimens will eat earth worms, chopped squid or even small feeder fish. The tail of the Antenna ray is really delicate and a newly imported specimen with a damaged tail is more likely to die. If its a small injury towards the end of the tail there are good chances it will heal but if it's near the base of the tail, it rarely heals and eventually falls off; once this happens, the ray will die. The cause of the death will probably be due to a bacterial infection entering the blood stream through the broken tail.
Such injuries usually happen in transit but in the aquarium are also likely to happen. Intake tubes or powerheads are often the cause but netting the fish is also dangerous for them, since the tail can get stuck in the net.
This group is best kept in a tank without ornamentation, bulky equipment or other fish. Gravel substrates are ok for this species but young ones should be kept in bare-bottom tanks to make feeding easier.
There is a type of Antenna Ray called a "Black Tailed Antenna Ray". This type seems to be less sensitive to tail injuries than the common antenna ray. This is the only species of Freshwater Stingray that commonly rests with its disc margin elevated off the substrate when in good health. (Do not confuse with "death curl").
The reason for them to hold their disc in such ways is not known.
The Black Tailed Antenna Ray is a dwarf stingray and even when adult has trouble eating anything larger than black worms, blood worms or tubifex. If you feed live worms, before feeding stir the substrate a little bit to make sure any survivor worms are eaten before they colonize your tank.
Such injuries usually happen in transit but in the aquarium are also likely to happen. Intake tubes or powerheads are often the cause but netting the fish is also dangerous for them, since the tail can get stuck in the net.
This group is best kept in a tank without ornamentation, bulky equipment or other fish. Gravel substrates are ok for this species but young ones should be kept in bare-bottom tanks to make feeding easier.
There is a type of Antenna Ray called a "Black Tailed Antenna Ray". This type seems to be less sensitive to tail injuries than the common antenna ray. This is the only species of Freshwater Stingray that commonly rests with its disc margin elevated off the substrate when in good health. (Do not confuse with "death curl").
The reason for them to hold their disc in such ways is not known.
The Black Tailed Antenna Ray is a dwarf stingray and even when adult has trouble eating anything larger than black worms, blood worms or tubifex. If you feed live worms, before feeding stir the substrate a little bit to make sure any survivor worms are eaten before they colonize your tank.
