Freshwater mussels provide several ecosystem services that are critical for maintaining healthy aquatic ecosystems; however, many species are experiencing population declines. Since mussels require a host fish to complete their life cycle, their reproductive success and distribution is dependent on suitable host fishes. Prior research has primarily focused on successful metamorphosis in lab conditions to identify host species; however, lab propagation does not confirm suitability of fish as hosts in natural settings. Assessing mussel glochidia on host fishes collected in the wild can increase understanding of host fish use by freshwater mussels. This study used morphometrics to identify species of freshwater mussel larvae (glochidia) found on 15 freshwater fish species collected from lakes and rivers in four U.S states along the Atlantic Slope. Fishes were collected in late spring and summer 2023 and 2024, with gills and fins preserved in 95% ethanol. Glochidia were extracted from fish, photographed using a compound microscope and camera, and analyzed with SPOT imaging software. Measurements of shell length, height, and hinge length were taken, along with documentation of shell shape, color, and hooks. Preliminary species identification was based on visual comparisons with existing glochidia morphology studies. A Principal Components Analysis based on the three shell measurements was used to further refine these preliminary identifications. The findings can identify ecologically-relevant host fishes, particularly when metamorphosis has already been confirmed in the lab. Understanding host fish dynamics will aid managers in assessing the potential distribution and population viability of freshwater mussels.