The name of Odostomia seminuda refers to the fact that it looses some, but
not all of its sculpture on the later whorls. The early whorls have both
strong spiral ridges and strong axial sculpture, giving a reticulated
appearance. The later whorls of a mature specimen lack the axial sculpture
and have reduced spiral sculpture. So, they are partially denuded of
sculpture - hence seminuda.
Paul M.