Figure 1.

Variability of potential metabarcoding markers in representative insects (40 species from 25 different orders): (a) mtDNA COI (5′ region), (b) mtDNA 16S (5′ region), (c) mtDNA 12S and (d) nuclear 18S (5′ region). Data were extracted from full mtDNA datasets and comparable nuclear 18S rRNA gene sequences. Entropy represents a measure of variability at a given position and shading in highlighted primer sites shows the four nucleotides. The COI primers have been applied in over a dozen metabarcoding studies; see the electronic supplementary material for details. (Online version in colour.)