The twelve bacterial replicons of the BMock12 Community Standards were used as reference. It includes the following strains: Species Sample ID Depth of Coverage (x) Muricauda sp. ES.050 2615840527 618.76 Thioclava sp. ES.032 2615840533 78.32 Cohaesibacter sp. ES.047 2615840601 170.59 Propionibacteriaceae bacterium 2615840646 31.90 Marinobacter sp. LV10R510-8 2615840697 447.83 Marinobacter sp. LV10MA510-1 2616644829 135.05 Psychrobacter sp. LV10R520-6 2617270709 425.47 Micromonospora echinaurantiaca 2623620557 14.91 Micromonospora echinofusca 2623620567 18.19 Micromonospora coxensis 2623620609 0.02 Halomonas sp. HL-4 2623620617 507.08 Halomonas sp. HL-93 2623620618 579.87 The raw sequence data of the mock communities, with an even distribution of species, is available at: SRR8073716 For the sake of a less resource-intense evaluation we downsampled to have 20% of the reads available in the original sample and further processed only these. The main challenges of this data set are possibly to assemble the genomes of the three Micromonospora spp. and the two Halomonas spp. strains, which have an ANIb >0.84 and 0.98, respectively. The two Marinobacter spp. have an ANIb of 0.78.