Sampling localities used in this study. Colors correspond to taxonomic status assigned at time of collection. Red, Glyphis gangeticus; green, G. sp. 1; blue, G. siamensis; white, G. fowlerae; pink, G. sp. 2; black, G. glyphis; yellow, G. garricki. Solid symbol outlines indicate samples with detailed locality information. Dashed outlines indicate samples for which detailed locality information is not available.