Número de Espécies

Figure 1. Relative proportions of named species in (a) the four subphyla constituting the Arthropoda and (b) the orders in the Insecta, with numbers in parentheses. A full breakdown of orders within the Arthropoda is in the Appendix. Data from the Catalogue of Life summarized by Zhang

Figure 2. Estimates of the global species richness of insects and terrestrial arthropods, in millions of species, against year (data from Table 1).

Table 2. Estimates for the numbers of terrestrial arthropod, insect, and beetle species in different biogeographical regions (38) based on the percentage distribution of the world's plant species (for example, for Australasia, the number of arthropod species is 13.10% of the total of arthropod species worldwide—890,799)

he number of flowering plants for North America given here and derived from Joppa et al. (30) is considerably lower than the recent estimate of 18,600 species for this region by the Missouri Botanical Gardens (http://www.missouribotanicalgarden.org/media/fact-pages/flora-of-north-america.aspx). This suggests that more work needs to be done to determine how plant species are distributed globally; hence the figures given in Table 2 for how insect species are distributed are just a first estimate.