Metaxia duplicarinata is a species of marine gastropod mollusc in the family Triphoridae.

[1] It was first described by Baden Powell in 1940, under the name Mendax duplicarinata.

Metaxia duplicarinata has a uniformly glossy white conical shell.

[2] The nuclear whorls are slightly angular.

[4] It differs from Metaxia maoria by having four instead of five spirals per whorl.