We characterized 10 new microsatellite markers in each of two species of hydromedusae, Maeotias
marginata and Moerisia sp. Genetic diversity was estimated using 20–41 individuals collected from Suisun Marsh within the San Francisco Estuary, CA. Allelic richness ranged from 5–9 in M.
marginata and 2–10 in Moerisia sp. with average expected heterozygosities of 0.71 and 0.57 respectively. One locus in M.
marginata and two in Moerisia sp. deviated from Hardy–Weinberg equilibrium expectations, likely due to null alleles.