Negative control sample (Blanco10) for the PCR, library preparation and sequencing steps
A 418 bp fragment from the 3' end of the mitochondrial COI barcode region (bc3') was amplified using primers Ill-B-F and Fol-degen-R with Illumina adapter tails. Three independent PCR reactions were performed per sample and pooled. Amplicons were purified using AMPure XP magnetic beads and used as template for a limited-cycle PCR to incorporate dual-index barcodes and Illumina sequencing adapters.