Dineth A. Danushka

Lankascincus fallax is an endemic, but widespread species of skink distributed throughout Sri Lanka, including all bioclimatic zones (elevations from 0 to 1,200 m a.s.l.). After thoroughly comparing morphology and morphometry between populations in different bioclimatic zones, we recognize it as a single morphospecies. We revise the systematics of Lankascincus fallax based on molecular and morphological data providing a comprehensive re-description of the adult syntype collected from either Ratnapura or Trinkomalee (sic), Sri Lanka. We provide the first-ever constructed phylogeny of Lankascincus representing five species (out of nine) based on GenBank data. In addition, we examined all the type specimens of the two synonymized species, Sphenomorphus rufogulus and Lankascincus deraniyagalae. We also provide a comprehensive discussion on the distribution of L. fallax.

Lankascincus dorsicatenatus is an endemic species of litter-skink distributed throughout the wet zone of Sri Lanka (elevations from 15 to 800 m a.s.l.). The recent resurrection of Lygosoma megalops by the recent description of its neotype designated by Batuwita (2019), presently lost, destabilized the taxonomic status of Lankascincus dorsicatenatus. Amarasinghe et al. (2022) synonymized Lygosoma megalops with Lankascincus fallax, and accepted Lankascincus dorsicatenatus as a valid taxon. Deraniyagala (1953) described Sphenomorphus dorsicatenatus based on a holotype and three paratypes. All the types are lost except one paratype at the National Museum of Sri Lanka, Colombo, Sri Lanka (NMSL), but it is in bad condition. Therefore, with a comparative discussion on the status of ‘Lankascincus megalops‘, here we designate a neotype for Lankascincus dorsicatenatus for clarification of the taxonomic status and stabilize the nomen. A discussion on the distribution and conservation of Lankascincus dorsicatenatus is also provided.