The leafhopper genus Thaia Ghauri, 1962 and two related genera, Parathaia Kuoh, 1982 and Pseudothaia Kuoh, 1982, are revised. Nlunga Dworakowska, 1974, previously treated as a subgenus of Thaia, is elevated to the genus level, and Parathaia Kuoh, 1982, previously treated as a synonym of Thaia, is reinstated to valid status. The Oriental species lacking foveae on the pronotum are excluded from Nlunga and transferred to a new genus, Etmaria gen. n. Two species, Pseudothaia caudata Song Li, 2013 and Thaia (Nlunga) leishanensis (Song Li, 2007), are treated as Incertae sedis within Erythroneurini. Moreover, nine additional new species are described and illustrated: Nlunga parareeneni, Etmaria brevis, E. chaiyaphumica, E. dentata, E. indonesica, E. magna, E. triquetra, E. ulterior and Pseudothaia forcipis spp. nov.