Three species (1 new) of HaliotrematoidesKritsky, Yang, and Sun, 2009 (Dactylogyridae), are described from the gill lamellae of porgies, Calamus spp. (Perciformes: Sparidae), from the northern Gulf of Mexico off Florida: Haliotrematoides parvicirrus (Zhukov, 1983) Kritsky, Yang, and Sun, 2009, from littlehead porgy Calamus proridens Jordan and Gilbert and knobbed porgy Calamus nodosus Randall and Caldwell (both new host records); Haliotrematoides bostryx n. sp. from C. proridens (type host), C. nodosus, jolthead porgy Calamus bajonado (Bloch and Schneider), and grass porgy Calamus arctifrons Goode and Bean; and Haliotrematoides mediohamus (Zhukov, 1983) Kritsky, Yang, and Sun, 2009, from C. proridens, C. nodosus, and sheepshead porgy Calamus penna (Valenciennes) (all new host records). Locations from which H. parvicirrus and H. mediohamus were collected in the northern Gulf of Mexico represent new geographic records for these species.