Table 1.

The Earth's most species-rich tropical ecoregions dominated by grassy biomes (including only ecoregions larger than the median, 62 300 km²). Vertebrate species richness (a) relates to the mean of species richness in 10 × 10 km cells, while for vascular plants (b), it is the total number of species present in the ecoregion. The ‘rank’ represents the global ranking of each ecoregion (out of 412 large ecoregions) in terms of species richness; in the case of vertebrates, it is a composite ranking, taking into account the species richness of all three taxa. The ecoregions are sorted according to the rankings. The cell shading indicates ecoregions which are common between (a) and (b), i.e. they are in the 20 most highly ranked TGBs in terms of both vertebrate and vascular plant species richness.

^aEcoregions considered biodiversity hotspots by Myers et al. [47].