This species is endemic to Terre-de-Bas and Terre-de-Haut which make up the Îles de Saintes, part of Guadeloupe. Terre-de-Bas and Terre-de-Haut are very small islands with a total area of approximately 16 km².
Hedges, S.B., Mayer, G.C. & Powell, R. 2010. Alsophis sanctonum. In: IUCN 2010 . IUCN Red List of Threatened Species. Version 2010.4 . <www.iucnredlist.org>