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||P.1 left column bottom paragraph: "Interestingly, several targets explicitly mention “known species”—a strong, if implicit statement of incomplete knowledge. So how many eukaryote species are there (primary source 4)? For land plants, there are 298,900 accepted species’ names, 477,601 synonyms, and 263,925 names unresolved (primary source 5). Because the accepted names among those resolved is 38%, it seems reasonable to predict that the same proportion of unresolved names will eventually be accepted. This yields another ~100,000 species for a total estimate of 400,000 species (primary source 5). Models predict 15% more to be discovered (primary source 6), so the total number of species of land plants should be >450,000 species, many more than are conventionally assumed to exist."