Characterization and comparison of poorly known moth communities through DNA barcoding in two Afrotropical environments in Gabon

Biodiversity research in tropical ecosystems—popularized as the most
biodiverse habitats on Eart —often neglects invertebrates, yet
invertebrates represent the bulk of local species richness. Insect
communities in particular remain strongly impeded by both Linnaean and
Wallacean short falls,and identifying species often remains a
formidable challenge inhibiting the use of these organisms as
indicators for ecological and conservation studies. Here we use DNA
barcoding as an alternative to the traditional taxonomic approach for
characterizing and comparing the diversity of moth communities in two
different ecosystems in Gabon. Though sampling remains very
incomplete, as evidenced by the high proportion (59%) of species
represented by singletons, our results reveal an outstanding
diversity. With about 3500 specimens sequenced and representing 1385
BINs (Barcode Index Numbers, used as a proxy to species) in 23
families, the diversity of moths in the two sites sampled is higher
than the current number of species listed for the entire country,
highlighting the huge gap in biodiversity knowledge for this country.
Both seasonal and spatial turnovers are strikingly high (18.3% of BINs
shared between seasons, and 13.3% between sites) and draw attention to
the need to account for these when running regional surveys. Our
results also highlight the richness and singularity of savannah
environments and emphasize the status of Central African ecosystems as
hotspots of biodiversity.