PCR-nucleic acid lateral flow immunoassay (NALFIA) with a combination of a single primer pair and a single DNA template. The respective DNA template is indicated above each cartridge. The (+) is indicating the positive control, (−) is indicating non-template control. The label on the left side of every pair of cartridges is indicating the test line for the existence of Ostrea edulis (FITC OE), Crassostrea gigas (632 CG), and Mytilus edulis (495 ME). The most upper line on the cartridges is indicating the control line of each NALFIA. The image of the 3% agarose gel electrophoresis gel shows the quality control of the PCR product. The scheme of the gel slots: 1: 50 bp marker, 2: empty, 3: OE x negative replicate 1, 4: OE x negative replicate 2, 5: empty, 6: OE x O. edulis replicate 1, 7: OE x O. edulis replicate 2, 8: empty, 9: CG x negative replicate 1, 10: CG x negative replicate 2, 11: empty, 12: CG x C. gigas replicate 1, 13: CG x C. gigas replicate 2, 14: empty, 15: ME x negative replicate 1, 16: ME x negative replicate 2, 17: empty, 18: ME x M. edulis replicate 1, 19: ME x M. edulis replicate 2, 20: empty, 21: 50 bp marker.