Dataset on the diversity of helminth parasites of freshwater fish in the headwaters of the Coatzacoalcos river, in Oaxaca, Mexico.

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).

Specifications Table

Value of the Data

These data are essential for phylogenetical and ecological hypothesis planing and further biogeographical studies; will assist to examine spatial variation in community structure of helminth parasites of freshwater fishes; may also assist to compare patterns of structure of assemblage vs appropriate null models; can be useful to compare population or community characteristics i. e. richness, densities, of tropical assemblages vs temperate or other regions.

These kinds of data could be useful for general biologists, biogeographers, ecologists and parasitologits. Also for aquaculturists and veterinarians involved in aquatic organism especially fish management and production; as well as regulatory agencies and stakeholders who seek to protect the public and their goods or values by limiting the adverse environmental impacts of development.

Parasite species knowledge of fishes and other aquatic organisms can be used to constraint controlled production of aquatic organisms or exploitation of natural resources. Likewise, environmental impact processes would take in account the likelihood that any aquacultural development will affect natural populations, native species or biodiversity in general, for example by accidentally introducing exotic, undesiderable alien species of parasites to the natural populations of fishes (see [1]; Salgado-Maldonado and Rubio-Godoy, 2015, [2] for examples).

These data could be used for providing an assessment of human impacts on the environment, or to generate data utile for a public awareness of conservation objectives. For example, host parasite systems knowledge can be used to indicate changes in the status of biodiversity [3]. As well these data could support to explore characteristics of the structure of parasite assemblages as nestedness or patterns of decay of similarity with distance.

Data Description

Table 1 contains the list of the fish species and the number of individual fish examined ordered alphabetically by fish family. Common names of the fish species and locations of collection are also referred in this table.

Table 1

Fish families and species, common names, localities (RJ: Jaltepec River, EP El Platanillo River; RE Escondido River; RN Negro River; RG Grande River; RM Modelo River; RP Pánfilo River), dates (Ap, April, Ma, March 2009) and number of hosts examined from the headwaters of the Coatzacoalcos river, Mexico.

	Common names	Locality	No. hosts examined
CHARACIDAE
Astyanax aeneus (Günther, 1860) [referred as Astyanax finitimus (Bocourt, 1868) by Schmitter-Soto, 2017]	Platilla, pepesca, Banded tetra	EP/Ma	19
		RN/Ma	24
		RG/Ma	1
		RP/Ap	20
		RJ/Ap	12
CICHLIDAE
Parachromis friedrichsthalii (Heckel, 1840)	Yellowjacket cichlid	RJ/Ap	1
Paraneetroplus bulleri Regan, 1905	Mojarra, Corrientero	EP/Ma	2
		RE/Ap	16
Theraps irregularis Günther, 1862	Arroyo cichlid	RN/Ma	6
Thorichthys callolepis (Regan, 1904)	Mojarra de San Domingo	RN/Ma	30
		RJ/Ap	7
Thorichthys helleri (Steindachner, 1864)	Mojarra amarilla, Yellow cichlid	RG/Ma	3
		RM/Ma	8
Thorichthys maculipinnis (Steindachner, 1864)	Mojarra	RE/Ap	1
Trichromis salvini (Günther, 1862)	Mojarra, Yellow belly cichlid	RN/Ma	9
		RG/Ma	1
		RM/Ma	1
		RP/Ap	3
		RE/Ap	3
		RJ/Ap	9
Vieja guttulata (Günther, 1864)	Mojarra de Amatitlán, Amatitlán cichlid	EP/Ma	24
		RN/Ma	29
		RE/Ap	10
		RJ/Ap	6
Vieja regani (Miller, 1974)	Mojarra pinta, mojarra de Almoloya, Almoloya cichlid	RG/Ma	5
		RM/Ma	5
ELEOTRIDAE
Gobiomorus dormitor Lacepède, 1800	Guavina, Bigmouth sleeper	RN/Ma	6
		RM/Ma	4
		RP/Ap	4
		RE/Ap	1
		RJ/Ap	1
GOBIIDAE
Awaous banana (Valenciennes, 1837)	Gobio de río	RN/Ma	8
		RM/Ma	1
HEPTAPTERIDAE
Rhamdia guatemalensis (Günther, 1864)	Juile, Bagre, Guatemalan chulin	RG/Ma	1
		RN/Ma	4
		RP/Ap	5
Rhamdia laticauda (Kner, 1858)	Bagre, Oaxaca catfish, Filespine chulín	RE/Ap	6
MUGILIDAE
Agonostomus monticola (Bancroft, 1834)	Lisa de río, Mulet	RN/Ma	1
		RP/Ap	2
		RE/Ap	2
POECILIIDAE
Poecilia mexicana Steindachner, 1863	Shortfin molly	RE/Ap	13
Poecilia sphenops Valenciennes, 1846	Guppi, Molly	RM/Ma	2
		RN/Ma	5
		RG/Ma	5
		RJ/Ap	10
Poeciliopsis gracilis (Heckel, 1848)	Porthole livebearer	RG/Ma	4
		RN/Ma	1
		RE/Ap	1
Priapella intermedia Álvarez and Carranza, 1952	Guayacón de los Chimalapas	RG/Ma	1
Pseudoxiphophorus bimaculatus (Heckel, 1848)	Guatopote manchado, Twospot livebearer	EP/Ma	4
		RN/Ma	1
		RP/Ap	8
Xiphophorus clemenciae Álvarez, 1959	Espadita, Yellow swordtail	RG/Ma	3
		RM/Ma	2
		RN/Ma	4
		RE/Ap	9
Xiphophorus mixei Kallman, Walter, Morizot and Kazianis, 2004	Mixe swordtail	EP/Ma	5
Xiphophorus monticolus Kallman, Walter, Morizot and Kazianis, 2004	Southern mountain swordtail	EP/Ma	9
Xiphophorus helerii Heckel, 1848	Espadita, Green swordtail	RJ/Ap	2
SYNBRANCHIDAE
Ophisternon aenigmaticum Rosen and Greenwood, 1976	Falsa anguila, Fatlips swamp eel	EP/Ma	5
		RG/Ma	1
		RM/Ma	1
		RN/Ma	3
		RE/Ap	7
		RJ/Ap	3

Table 2 is a list of fish host – parasite associations, including the tissues or organs of the fish from which parasites were collected, and the localities and date of collection of helminth parasites collected from the 25 fish species examined from upper Coatzacoalcos river, Oaxaca, Mexico. Helminth parasites are ordered by Platyhelminthes (Monogenea, Trematoda, Cestoda), Acanthocephala and Nematoda (adults first, then larval forms).

Table 2

Parasite – host associations, localities (RJ: Jaltepec River, EP El Platanillo River; RE Escondido River; RN Negro River; RG Grande River; RM Modelo River; RP Pánfilo River), and date of collection (Ap, April or Ma, March 2009), of helminth parasites collected from 25 fish species from upper Coatzacoalcos river, Oaxaca, Mexico

HELMINTH FISH HOST	SITE	LOCALITY, Date
MONOGENEA
Aphanoblastella travassosi (Price, 1938)
Rhamdia guatemalensis	Gills	RN, Ma
Rhamdia laticauda	Gills	RE, Ap
Guavinella tropica Mendoza-Franco, Scholz and Cabañas-Carranza, 2003
Gobiomorus dormitor	Gills	RN, RM, Ma; RE, Ap
Gyrodactylus sp.
Poecilia mexicana	Fins	RE, Ap
Thorichthys callolepis	Fins	RN, Ma
Vieja guttulata	Gills	RN, Ma
Salsuginus sp.
Xiphophorus monticolus	Gills	EP, Ma
Sciadicleithrum sp.
Paraneetroplus bulleri	Gills	RE, Ap
Thorichthys callolepis	Gills	RN, Ma
Vieja guttulata	Gills	EP, Ma; RJ, Ap
"Urocleidoides" cf. strombicirrus (Price and Bussing, 1967)
Astyanax aeneus	Gills	EP, RN, Ma; RP, Ap
TREMATODA
Auriculostoma astyanace Scholz, Aguirre-Macedo and Choudhury, 2004
Astyanax aeneus	Intestine	RG, Ma; RJ, Ap
Crassicutis cichlasomae Manter, 1936
Parachromis friedrichsthalii	Intestine	RJ, Ap
Paraneetroplus bulleri	Intestine	RE, Ap
Thorichthys helleri	Intestine	RM, Ma
Trichromis salvini	Intestine	RM, Ma; RP, RE, RJ, Ap;
Vieja regain	Intestine	RM, Ma
Creptotrema agonostomi Salgado-Maldonado, Cabañas-Carranza and Caspeta-Mandujano, 1998
Agonostomus monticola	Intestine	RN, Ma; RP, RE, Ap
Genarchella astyanctis (Watson, 1976)
Astyanax aeneus	Intestine	RP, RJ, Ap
Genarchella isabellae (Lamothe-Argumedo, 1977)
Gobiomorus dormitor	Intestine	RM, Ma
Thorichthys helleri	Intestine	RM, Ma
Vieja guttulata	Stomach	EP, RN, Ma
Vieja regain	Stomach	RM, Ma
Magnivitellinum cf. simplex Kloss, 1966
Astyanax aeneus	Intestine	RP, Ap
Paracreptotrematoides cf. heterandriae (Salgado-Maldonado, Caspeta-Mandujano and Vázquez, 2012)
Pseudoxiphophorus bimaculatus	Intestine	RP, Ap
Saccocoelioides cf. sogandaresi Lumsden, 1963
Agonostomus montícola	Intestine	RP, Ap
Poecilia sphenops	Intestine	RG, Ma
Poeciliopsis gracilis	Intestine	RG, Ma
Xiphophorus clemenciae	Intestine	RG, Ma
Wallinia anindoi Hernández-Mena, Pinacho-Pinacho, García-Varela, Mendoza-Garfías and Pérez Ponce de León, 2019
Astyanax aeneus	Intestine and intestinal caeca	RN, Ma; RJ, RP, Ap
METACERCARIAE
Apharyngostrigea sp.
Astyanax aeneus	Mesentery, Gall bladder	RN, Ma; RJ Ap
Ascocotyle (Phagicola) diminuta (Stunkard and Haviland, 1924)
Poecilia sphenops	Gills	RG, Ma
Centrocestus formosanus (Nishigori, 1924)
Astyanax aeneus	Gills	RN, Ma
Gobiomorus dormitor	Gills	RN, Ma
Pseudoxiphophorus bimaculatus	Gills	RP, Ap
Thorichthys callolepis	Gills	RN, Ma
Xiphophorus clemenciae	Gills	RN, Ma
Cladocystis cf. trifolium (Braun, 1901)
Thorichthys helleri	Intestine	RM, Ma
Trichromis salvini	Mesentery	RG, Ma
Clinostomum sp.
Astyanax aeneus	Gills, fins, mesentery	EP, Ma
Rhamdia guatemalensis	Mesentery, fins, gill cavity, mesentery	RN, Ma; RP, Ap
Rhamdia laticauda	Fins	RE, Ap
Thorichthys callolepis	Fins, skin, mouth, mesentery	RN, Ma
Vieja guttulata	Gill cavity	RN, Ma
Crocodilicola pseudostoma (Willemoes-Suhm, 1870)
Rhamdia guatemalensis	Intestine	RP, Ap
Diplostomum sp.
Poecilia sphenops	Eyes	RJ, Ap
Thorichthys callolepis	Eyes, gills	RN; Ma; Rj, Ap
Trichromis salvini	Eyes	RN, Ma; RJ, Ap
Vieja guttulata	Eyes, brain, mesentery	RN, Ma; RJ, Ap
Posthodiplostomum sp.
Parachromis friedrichsthalii	Mesentery	RJ, Ap
Paraneetroplus bulleri	Muscle, mesentery	RE, Ap
Poecilia sphenops	Mesentery	RG, Ma; Rj, Ap
Trichromis salvini	Muscle, eyes, mesentery	RJ, Ap
Vieja guttulata	Muscle, mesentery	RN, Ma
	Muscle	RJ, Ap
Vieja regain	Gills	RG, Ma
Tylodelphys sp.
Parachromis friedrichsthalii	Mesentery	RJ, Ap
Trichromis salvini	Mesentery	RJ, Ap
Uvulifer cf. ambloplitis (Hughes, 1927)
Astyanax aeneus	Skin, fins, muscle	EP, Ma
Paraneetroplus bulleri	Muscle	EP, Ma
Priapella intermedia	Fins	RG, Ma
Xiphophorus clemenciae	Fins	RG, Ma
CESTODA
Cichlidocestus sp.
Thorichthys callolepis	Intestine	RN, Ma
Vieja guttulata	Intestine	RN, Ma
Schyzocotyle acheilognathi (Yamaguti, 1934)
Vieja guttulata	Intestine	RJ, Ap
METACESTODE
Glossocercus sp.
Poecilia sphenops	Liver	RJ, Ap
ACANTHOCEPHALA
Neoechinorhynchus chimalapasensis Salgado-Maldonado, Caspeta-Mandujano and Martínez-Ramírez, 2010
Awaous banana	Intestine	RN, Ma
NEMATODA
Atractis vidali González-Solís and Moravec, 2002
Vieja guttulata	Intestine	RN, Ma
Capillariidae gen. sp.
Astyanax aeneus	Stomach	RP, Ap
Cucullanus angeli Cabañas-Carranza and Caspeta-Mandujano, 2007
Vieja guttulata	Intestine	EP, RN, Ma
Cucullanus mexicanus Caspeta-Mandujano, Moravec and Aguilar-Aguilar, 2000
Rhamdia guatemalensis	Mesentery	RP, Ap
Cucullanus sp.
Gobiomorus dormitor	Intestine	RE, Ap
Paraneetroplus bulleri	Intestine	RE, Ap
Thorichthys helleri	Intestine	RM, Ma
Vieja guttulata	Intestine	RE, Ap
Dichelyne mexicanus Caspeta-Mandujano, Moravec and Salgado-Maldonado, 1999
Agonostomus monticola	Intestine	RP, Ap
Parcapillaria teixeirafreitasi (Caballero-Rodríguez, 1971)
Gobiomorus dormitor	Stomach	RE, Ap; RN, Ma
Philometridae gen. sp.
Ophisternon aenigmaticum	Skin	EP, RN, Ma
Paraneetroplus bulleri	Body cavity	RE, Ap
Theraps irregularis	Muscle	RN, Ma
Procamallanus (Spirocamallanus) rebecae (Andrade-Salas, Pineda-López and García-Magaña, 1994)
Thorichthys helleri	Intestine	RG, RM, Ma
Thorichthys maculipinnis	Intestine	RE, Ap
Pseudocapillaria (Icthyocapillaria) ophisterni Moravec, Salgado-Maldonado and Jiménez-García, 2000
Ophisternon aenigmaticum	Mesentery	RE, Ap
Raillietnema kritscheri Moravec, Salgado-Maldonado and Pineda-López, 1993
Paraneetroplus bulleri	Intestine	RE, Ap
Thorichthys helleri	Intestine	RM, Ma
Trichromis salvini	Intestine	RJ, Ap
Vieja guttulata	Intestine	RN, Ma; RE, Ap
Vieja regain	Intestine	RG, Ma
Rhabdochona kidderi Pearse, 1936
Paraneetroplus bulleri	Intestine	RE, Ap
Rhamdia laticauda	Intestine	RE, Ap
Vieja guttulate	Intestine	EP, Ma; RE, Ap
Vieja regain	Intestine	RM, Ma
Rhabdochona sp.
Theraps irregularis	Intestine	RN, Ma
Spinitectus mexicanus Caspeta-Mandujano, Moravec and Salgado-Maldonado, 2000
Pseudoxiphophorus bimaculatus	Intestine	RP, Ap
LARVAL NEMATODES
Acuariidae gen. sp.
Astyanax aeneus	Intestine	EP, Ma
Paraneetroplus bulleri	Mesentery	EP, Ma
Trichromis salvini	Mesentery	RG, Ma
Xiphophorus mixei	Muscle	EP, Ma
Contracaecum sp.
Astyanax aeneus	Liver	RN, Ma; RP, Ap
Awaous banana	Mesentery	RN, Ma
Gobiomorus dormitor	Intestine, liver, muscle, mesentery	RM, RN, Ma; RE, RP, Ap
Ophisternon aenigmaticum	Body cavity, Mesentery	RG, RM, RN, Ma; RJ, RP, Ap
Paraneetroplus bulleri	Liver, mesentery	RE, Ap
Rhamdia guatemalensis	Mesentery	RG, Ma; RP, Ap
Thorichthys callolepis	Liver	RJ, Ap
Thorichthys helleri	Liver	RM, Ma
Vieja guttulate	Intestine, mesentery	RE, RJ, Ap
Vieja regani	Mesentery	RG, Ma
Xiphophorus hellerii	Mesentery	RJ, Ap
Falcaustra sp.
Gobiomorus dormitor	Intestine	RN, Ma
Poecilia mexicana	Intestine	RE, Ap
Hysterothylacium cenotae (Pearse, 1936)
Vieja guttulate	Intestine	RN, Ma
Rhabdochona sp. larvae or female unidentifiable to species
Gobiomorus dormitor	Intestine	RM, Ma; RP, Ap
Ophisternon aenigmaticum	Intestine	RE, Ap
Thorichthys helleri	Intestine	RM, Ma
Vieja guttulate	Intestine	RN, Ma
Spiroxys sp.
Astyanax aeneus	Mesentery	RJ, Ap; RN, Ma
Gobiomorus dormitor	Mesentery	RN, Ma
Poecilia mexicana	Mesentery	RE, Ap
Thorichthys callolepis	Mesentery	RN, Ma
Xiphophorus clemenciae	Mesentery	RG, Ma

Table 3 list the abbreviations to the scientific names of the taxa of helminth parasites used in Supplementary Table 4.

Table 3

Abbreviations to scientific names of helminth parasite taxa referred to in Supplementary Table 4.

Aas	Auriculostoma astyanace	Gyr	Gyrodactylus sp.
Acu	Acuariidae	Hce	Hysterothylacium cenotae (larvae)
Adi	Ascocotyle (Phagicola) diminuta	Msi	Magnivitellinum cf. Simplex
Aph	Apharyngostrigea sp.	Nch	Neoechinorhynchus chimalapasensis
Atr	Aphanoblastella travassosi	Phe	Paracreptotrematoides cf. heterandriae
Avi	Actractis vidali	Phi	Phillometridae gen. sp.
Cag	Creptotrema agonostomi	Pmi	Posthodiplostomum cf. minimum
Can	Cucullanus angeli	Pop	Pseudocapillaria ophistherni
Cap	Capillaria sp.	Pos	Posthodiplostomum sp.
Cci	Crassicutis cichlasomae	Pre	Procamallanus rebecae
Cfo	Centrocestus formosanus	Pte	Paracapillaria teixeirafreitasi
Cic	Cichidocestus sp.	Rha	Rhabdochona sp.
Cli	Clinostomum sp.	Rki	Rhabdochona kidderi
Cme	Cucullanus mexicanus	Rkr	Raillietnema kritscheri
Con	Contracaecum sp.	Sac	Schyzocotyle acheilognathi
Cps	Crocodilicola pseudostoma	Sci	Sciadicleithrum sp.
Ctr	Cladocystis trifolium	Sme	Spinitectus mexicanus
Cuc	Cucullanus sp.	Spi	Spiroxys sp.
Dip	Diplostomum sp.	Sso	Saccocoelioides cf. sogandaresi
Dme	Dichelyne mexicanus	Tyl	Tylodelphis
Fal	Falcaustra sp.	Uam	Uvulifer ambloplitis
Gas	Genarchella astyanctis	Ust	Urocleidoides cf. strombicirrus
Gis	Genarchella isabellae	Wan	Walliniea anindoi
Glo	Glossocercus sp.
Gtr	Guavinella tropica

Supplementary Table 4. document the raw data on helminth parasites of 25 fish species from the Headwaters of Coatzacoalcos river, Mexico. One matrix for each fish species ordered alphabetically by fish families (see Table 1). Data include the name of the locality, coordinates in decimal degrees, altitude meters above sea level, date of collection, host number in the author's field notes, host’ sex; host’ measurements documented for each one fish examined; and the raw number of helminth parasites recorded from each fish host.

Experimental design, materials and methods

We gathered data from a total of 410 freshwater fish from 25 species and eight families during March and April 2009. Fishes were caugh at the upper reaches of the Coatzacoalcos River basin. The area of study is located ∼300 km from the mouth of the Coatzacoalcos river in the Gulf of Mexico. We examined from 1 to 30 individuals of every available fish species from each of seven locations. Sample locations were chosen as follows: 1. El Platanillo river, tributary to Del Sol river (municipality Santo Domingo Petapa), coordinates 16.951111, -95.244167, altitude 416 m; 2. Río Grande (El Barrio), 16.792167, -95.016083, 220 m; 3. Río Negro (Santa María Chimalapa), 16.898528, -94.693694, 166 m; 4. Río Modelo (Santa María Chimalapa), 17.134778, -94.745000, 115 m; 5. Río Pánfilo (Matías Romero, Oaxaca), 17.083639, -94.873944, 60 m; 6. Río Jaltepec (Jesús Carranza, Veracruz), 17.388444, -95.056111, 40 m; 7. Río Escondido (Paraje San Francisco El Vado, Agencia Municipal Río Escondido, Santa María Chimalapa), 17.091083, -94.751694, 103 m. Note all sites in Oaxaca state, except # 6, which is in Veracruz state, Mexico. At each locality, fish were captured using nets or electrofishing device. Live fish were brought to the laboratory and examined within 8 h of capture using standard procedures. Briefly, all the external surfaces, víscera, and musculature of each fish host were examined under a stereomicroscope, and all the helminths encountered in each fish were counted. Two kinds of data were collected from each individual fish: the number of helminth taxa (species richness) in each fish and the number of helminth individuals per helminth taxa (the abundance distribution). All helminths found were isolated and counted, and then fixed in 4% hot formaldehyde (cestodes, monogeneans and adult digeneans, as well as larvae of digeneans and nematodes). Some monogeneans were fixed with ammonium picrate [4] and mounted unstained in Gray–Wess medium [5], for analysis of sclerotized structures. Acanthocephalans were placed in distilled water, refrigerated overnight (6–12 h) to evert the proboscis, and then fixed in hot 10% formalin. Digeneans, monogeneans, cestodes, and acanthocephalans used for morphological examination of whole mounts, were stained with either Mayer's paracarmine or Gomori´s triple stain dehydrated using a graded alcohol series, cleared in methyl salicylate, and and mounted whole in Canada balsam. Nematodes were cleared in glycerine for light microscopy and stored in 70% ethanol. Taxonomic identification was performed based on morphometric analysis of the specimens [6].

Ethics statement

Fish were euthanized and the branchial arches were removed, separated from the brachial cavity and evaluated individually (protocol for the use of fish in research based on the NORM – 019 – STPS – 1993 established by the Instituto de Ecología, Pesquerías y Oceanografía del Golfo de México EPOMEX, Campeche, Mexico; specimens collected under the Cartilla Nacional de Colector Científico FAUT-0105 issued by the Secretaría del Medio Ambiente y Recursos Naturales [SEMARNAT] to GSM).

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Subject area	Biology; Animal science and Zoology.
Specific subject area	Platyhelminthes, Nematoda and Acanthocephala. Helminth ecto- and endo-parasites of tropical freshwater fish of northern end of Central America.
Type of data	Table.
How data were acquired	Microscope, survey. Each fish was examined under a stereo microscope in Petri dishes with river water for external examination, and with 0.6% saline solution for internal organs. External examination included the skin, scales, mouth, gill cavity, anus, and fins of each host; while internal examination included the brain, gut, mesenteries, kidneys, liver, gall bladder and muscles. We collected data on the number of species (species richness) and abundance distribution of helminths (number of individuals of each species).
Data format	Raw numbers in matrices of localities and fish-individual (lines) vs characteristics (location coordinates and altitude; host length, weigh and sex), and helminth parasite taxa (columns) recorded in each one fish host individually. A matrix per each one of 25 fish species.
Description of data collection	We examined 410 freshwater fishes from 25 species and eight families during March and April 2009; at seven sites in the headwaters of the Coatzacoalcos river basin.Fish were collected using electrofishing device, transferred to the laboratory and kept alive in aerated containers until they were examined for helminths, performed within 8 hours of capture. Each fish was measured (total and standard length; maximum deep) and examined under a stereo microscope in Petri dishes with river water (for external organs) or saline 0.6% solution (for internal organs inspection). Skin, scales, mouth, gill cavity, anus, and fins, as well as all internal organs and tissues except the blood and bones, of each host were examined. Fish were euthanized and the gill arches were removed, separated from the gill cavity and evaluated individually. After, internal organs were excised and examined for helminths under stereomicroscope.
Parameters for data collection	The platyhelminths (monogenea and digenea) and the acanthocephalan found were fixed in 4% hot formaldehyde, stained with Mayer's paracarmine or Gomori´s triple stain and mounted whole on Canada balsam, to made permanent slides for microscopical examination. Nematodes were fixed also in 4% formalin and studied in nonpermanent slides with glycerin. Taxonomic identification was performed based on morphometric analysis of the specimens. A total of 48 helminth species are documented from 44 genera and 29 families.
Data source location	MEXICO (Isthmus of Tehuantepec zone, southeastern of the country) Northermost end of Central America. Seven sample locations situated on the upper Coatzacoalcos river: 1. El Platanillo river, tributary to Del Sol river (municipality Santo Domingo Petapa), coordinates 16.951111, -95.244167, altitude 416 m; 2. Río Grande (El Barrio), 16.792167, -95.016083, 220 m; 3. Río Negro (Santa María Chimalapa), 16.898528, -94.693694, 166 m; 4. Río Modelo (Santa María Chimalapa), 17.134778, -94.745000, 115 m; 5. Río Pánfilo (Matías Romero, Oaxaca), 17.083639, -94.873944, 60 m; 6. Río Jaltepec (Jesús Carranza, Veracruz), 17.388444, -95.056111, 40 m; 7. Río Escondido (Paraje San Francisco El Vado, Agencia Municipal San Francisco El Vado, Santa María Chimalapa), 17.091083, -94.751694, 83 m. Note all sites in Oaxaca state, except # 6, which is in Veracruz state.
Data accessibility	Data provided within this article.
Related research article	Salgado-Maldonado, G., Caspeta-Mandujano, J. M., Martínez-Ramírez, E., Montoya-Mendoza, J., and Mendoza-Franco, E. F., Diversity of helminth parasites of freshwater fish in the headwaters of the Coatzacoalcos river, Oaxaca, Mexico. International Journal for Parasitology: Parasites and Wildlife, 12: 142 - 149. doi.org/10.1016/j.ijppaw.2020.05.008