Data of the Insect Biome atlas: a metabarcoding survey of the terrestrial arthropods of Sweden and Madagascar

We present the data from the Insect Biome Atlas project (IBa), characterizing the terrestrial arthropod faunas of Sweden and Madagascar. Over 12 months, Malaise trap samples were collected weekly (biweekly or monthly in the winter) at 203 locations within 100 sites in Sweden and weekly at 50 locations within 33 sites in Madagascar, complemented by soil and litter samples. Samples were processed using mild lysis or homogenization followed by DNA metabarcoding of a 418 bp fragment of the cytochrome c oxidase subunit I (CO1) gene. The data comprise 698,378 non-chimeric sequence variants from Sweden and 687,866 from Madagascar, representing 33,989 and 77,599 operational taxonomic units, respectively. These datasets provide comprehensive insights into the diversity, composition, spatial turnover, and seasonal dynamics of terrestrial arthropod communities and serve as an invaluable baseline for future monitoring.