Abstract
The data presented in this article are related to the research article entitled " Diversity of helminth parasites of freshwater fish in the headwaters of the Coatzacoalcos river, in Oaxaca, Mexico " published in International Journal for Parasitolology: Parasites and Wildlife. This dataset document the diversity of helminth parasites found in 25 fish species from 8 families from rivers in the headwaters of the Coatzacoalcos river basin at the border between Oaxaca and Veracruz states, Isthmus of Tehuantepec zone, southeastern Mexico, in the northernmost end of Central America. We record here 48 species, 44 genera and 29 helminth families. Most of the helminth species recorded in this area has also been collected from Central American bodies of freshwater south of Mexico. The material in this Data in Brief paper comprised the raw data on the abundance distribution of each helminth taxa recorded in each of the host and location; i. e. the number of helminth individuals of each helminth taxa found in each one individual fish from each species from each of the localities sampled. The data set is contained in one text-table matrix per fish-host, date of collection and locality of helminth taxa (lines) per fish host species (columns).