Between May 2014 and September 2014, 50 Northern Studfish, Fundulus catenatus, were collected from sites in the interior highlands of the Ouachita Mountains (n  =  25) and Ozark Mountains (n  =  25) of Arkansas and examined for helminths. Twenty-three (46%) of the northern studfish, including 7 (28%) from the Ouachitas and 23 (92%) from the Ozarks were infected with helminths. These included 8 (16%) with Neascus-type metacercariae (black grub), 4 (8%) with metacercaria of Clinostomum marginatum, 8 (16%) with Creptotrema sp., 1 (2%) with Posthodiplostomum minimum, 3 (6%) with immature Proteocephalus sp., 9 (18%) with larval Eustrongylides sp., 1 (2%) with Rhabdochona cascadilla, 2 (4%) with larval Spinitectus sp., and 17 (34%) with acanthocephalan cystacanths. In addition, 6 of 8 individuals (75%) from one site in the Ouachitas harbored the monogenean, Salsuginus fundulus. We document new host records for most of these helminths and new distributional records for Creptotrema sp., Eustrongylides sp., and S. fundulus.