Dynamine postverta, the Mylitta greenwing or four-spot sailor, is a butterfly in the family Nymphalidae.

It is found throughout most tropical and subtropical areas of Central and South America, from Mexico south to Argentina and Paraguay.

[2] The habitat includes primary rainforests, humid deciduous woodlands, scrubby grassland and farmland at altitudes up to about 900 metres.

The larvae feed on Dalechampia species.

This article related to members of the butterfly subfamily Biblidinae is a stub.