The evolutionary impacts of whole genome duplication events are still unclear. We collected parasite count data and immune gene molecular data for Toll like receptor (TLR) 1 and TLR2 in two catfish species; Corydoras maculifer (diploid) and Corydoras araguaiaensis (putative allotetraploid). Our aim was to compare parasite load and immune gene diversity between these two species. 

Samples of the host fish species Corydoras maculifer (n= 20) and Corydoras araguaiaensis (n=41) were collected from the Rio das Mortes drainage of the Araguaia River in Mato Grosso state, Brazil in 2012 and 2015. All samples were euthanised by anaesthetic overdose and preserved individually in 100% ethanol. In addition samples from 2015 were dissected in the field; stomach, liver and digestive tract were preserved separately in 100% ethanol. Tissues, the external body and body cavity of the host fish were then manually screened for parasites using a disecting microscope and fiber optic illumination.

Parasite count and prevalence data are included here along with the r scripts used for modeling (GLM) the relationship between host standard length and parasite counts. 

Immunogenetic data was collected from PCR amplified Toll like receptor (TLR) 1 and TLR2, raw sequence data was submited to Sequence Read Archive submission: SUB7660075 (individual accision numbers included in file uploads). FreeBayes was used to identify variants in the immune gene data, corresponding vcf files are inluded in these uploads. 

These data were used alongside immune gene data sets that have been uploaded to Sequence Read Archive (SRA), submission: SUB7660075.