As a part of an ongoing revision of Sri Lankan scincid lizards, I review the genus Lankascincus Greer on the basis of their morphology and morphometric data. I demonstrate that the long-disputed Sphenomorphus megalops (Annandale) is in fact a Lankascincus species, and a neotype is designated. Lankascincus deraniyagalae Greer and L. munindradasai Wickramasinghe, Rodrigo, Dayawansa, and Jayantha are shown to be junior subjective synonyms of L. fallax (Peters) and L. taprobanensis (Kelaart), respectively. Lankascincus deignani (Taylor) is confined to the forests around Kandy and does not extend to Nuwaraeliya and its environs. Previous records of L. deignani from Nuwaraeliya and surrounding localities are reidentified as L. sripadensis Wickramasinghe, Rodrigo, Dayawansa, and Jayantha. Three groups of Lankascincus species are identified on the basis of their morphology and breeding biology: the fallax, taprobanensis, and dorsicatenatus groups. Each group has a unique combination of characters. Lankascincus taprobanensis is restricted to high-elevational regions (≥1,500 m above mean sea level). Previous records from lower elevations (Sinharaja, Knuckles Range, and Peradeniya) are based on misidentified specimens of other Lankascincus spp. Lankascincus fallax has a wide distribution in Sri Lanka. Lankascincus deignani is restricted to Gannoruwa Forest Reserve and the Ambagamuwa area and is the most endangered skink in Sri Lanka. Ecologically, Lankascincus comprises a largely forest-dwelling species group (L. deignani, L. dorsicatenatus (Deraniyagala), L. gansi Greer, L. greeri Batuwita and Pethiyagoda, L. megalops new combination, and L. taprobanensis) and a group of species that live in altered habitats (L. sripadensis, L. fallax, and L. taylori). The present study confirms that the genus Sphenomorphus Fitzinger is not represented in Sri Lanka. Because of a lack of comprehensive genetic data to support a previously described new family, Ristellidae Hedges for Lankascincus and Ristella Gray, here I assign both genera into a new tribe, Ristellini. Phylogenetic relationships of Lankascincus and Ristella remain unresolved.