A depth-generalist coral species, Montastraea cavernosa, was sampled across a shallow to mesophotic gradient at 10, 15, 25, and 35 m at Alacranes and Bajos del Norte reefs on Campeche Bank, Mexico. Both 2bRAD and ITS2 sequencing were used to quantify genetic differentiation of the coral hosts and community structure of their algal endosymbionts (Family Symbiodiniaceae) across depth zones and between these reefs.