Characteristic features are a long filiform tail, reduced eyes, and a low number of pectoral-fin radials.

Their prey includes worms, crustaceans, mollusks, and small bottom fish (such as small catfish). 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. Previously misidentified, or unidentified, specimens were then found in other museums.

This fish seldomly appears in the aquarium trade.

References

• Ricardo S. Rosa; Hugo P. Castello; Thomas B. Thorson (1987). "Plesiotrygon iwamae, a New Genus and Species of Neotropical Freshwater Stingray (Chondrichthyes: Potamotrygonidae)". Copeia 447–458.