Description: Shell medium for the genus (up to 100.5 mm), thin but solid. Shape slender, spire high. Sculpture consisting of prominent spiral sculpture with deep, narrow interspaces.
Type locality: "Japan, off Miyake Island". The shell figured by Okutani was from: 34° 03.7' N, 140° 06.7' E,off Miyake Island, 1180 m. Range: The species is only known from the type material off Miyake. No additional material has been caught and there has been no opportunity for a comparative study.
Comparison: Neptunea acutispiralis has a characteristically "acute" spiral sculpture, as indicated by the name, with narrow interspaces.
Neptunea jagudinae differs in the spiral cords, which are higher in number and have a flattened top, by the broader shape and a more northern range.