Erythrodiplax unimaculata, also known by its common name white-tailed dragonlet is a species from the genus Erythrodiplax.

 This species has wings with brown tips, but female samples often only have basal spots on the wings. Forewings can have a yellowish shadow. For the hind wings the red-yellow color is somewhat more widespread, diffuse anteriorly and not very sharp up to the 1st antenodal transverse artery and on or a little over the transverse artery of the submedian space

Taxonomy: Erythrodiplax unimaculata was first described by Charles De Geer in 1773. Monophyly has not yet been determined

Range: Observation of Erythrodiplax unimaculata have been documented in Brazil, Colombia and Peru. Observations aggregated in the Global Biodiversity Information Facility suggest a more wide spread range in the northern have of South America.