[1] It lives in the main channel of the Amazon River and lower parts of its major tributaries.

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

[3] It resembles the black-tailed antenna ray (P. nana),[2] but is larger at up to 58 cm (1.90 ft) in disc width.

[3] The fish is named in honor of the zoologist Satoko Iwama (d. 1987) of the Instituto de Botânica in São Paulo (Brazil).

Although the species is sensitive and the tail is easily damaged, this fish occasionally appears in the aquarium trade and it has been bred in captivity.