Prepared under contract from the European Commission Grant agreement No. 101059492 EU Horizon Europe Research and Innovation action We retrieved reliable genome size estimations from 165 samples, from 10 phyla (Porifera, Cnidaria, Annelida, Nemertea, Platyhelminthes, Brachiopoda, Mollusca, Echinodermata, Arthropoda, Chordata), and 73 species. For these samples, nuclei were easily identifiable in the samples, they were all similar in size, their staining was consistent, and their morphology did not vary extensively . It is important to note here, that nuclei measurements were easily performed in samples with small nuclei, like the sponge samples, where most nuclei could be measured in two or three different pictures , while large nuclei containing massive genomes occupied almost the entire picture, like in the crustacean Systellaspis debilis , making it more tedious to measure one nucleus per picture (to totalize 30 per sample). [MOU1]if this is in the milestone, no need to repeat it here just refer to the milestone [MOU2]I think that since the milestone is not public, we might as well show it here.