Adult, gravid female Neoergasilus japonicus Harada, 1930 are described from several species of fish from Lee County, Alabama. Samples of bluegill Lepomis macrochirus Rafinesque (n = 25), largemouth bass Micropterus salmoides Lacépéde (n = 6), redear sunfish Lepomis microlophus Gunther (n = 5), and channel catfish Ictalurus punctatus Rafinesque (n = 1) were collected between November 1993 and May 1995. Prevalence of infection was 100% in all fish collected. The dorsal fin was the site of infection containing the highest number of parasites and the anal fin showed the highest frequency of infection. Morphological comparisons are made between this report and previous descriptions, and disparities among them are indicated. New hosts for N. japonicus include largemouth bass, channel catfish, and redear sunfish. This report is the first North American record for the genus Neoergasilus.