Liopeltis calamaria, a rare non-venomous colubrid snake of South Asia, is redescribed. Its syntypes and all the available type specimens of its recognized synonyms are examined, including information about the respective populations found across India and Sri Lanka. Our literature compilation and mapping analyses reveal three distinct populations – (I) Sri Lankan (probably also present in some parts of South India as well), (II) Peninsular Indian, and (III) Himalayan / Nepalese, separated by the Palk Strait and the Indo-Gangetic plains respectively.