Costularia is a plant genus in the family Cyperaceae.

[2][3][4][5] It includes 15 species native to southeastern Africa, ranging from South Africa (KwaZulu-Natal and Northern Provinces) through Eswatini, Mozambique, Zimbabwe, and Malawi, and to the islands Madagascar, Réunion, and the Seychelles in the Western Indian Ocean.

[1][6] The genus was formerly circumscribed to include 25 species.

A molecular phylogenetic study found that circumscription to include four distinct lineages: In 2019, the genus was revised to include 15 species, generally corresponding to Costularia s.s. and including a few previously undescribed species.

This Cyperaceae article is a stub.