The distribution of the species Corydoras cf. garbei in the Pajeú river basin is restricted to certain specific habitats and, therefore, it is necessary to understand the distribution of the species in this important river basin. The objective of this study was to detect the species C. cf. garbei using the eDNA method. For this, we performed a targeted approach using two pairs of primers (universal and species-specific) in a conventional PCR for detection of the target species. eDNA samples for eight sampling points were amplified using two pairs of primers and the presence of the target species was confirmed only at one sampling point. We conclude that the conventional PCR approach was considered effective in monitoring the target-species, but improvements in the standardization of the eDNA are necessary for continued use in the semiarid region of the Caatinga biome.