Data from: Evolutionary history of the flora of Mexico: dry forests cradles and museums of endemism

Mexico is considered an exceptional biogeographic area with a varied and
unique endemic vascular flora that is estimated at half of the global
total of approximately 24,500 species. However, spatial phylogenetic
measures of biodiversity for this flora have not yet been estimated to
understand how the Mexican flora assembled to form current vegetation.
Patterns of species richness, weighted endemism, phylogenetic diversity
and weighted phylogenetic endemism, as well as centers of neo- and
paleo-endemism were determined to examine differences and congruence among
these measures, and the implications of these results for conservation.
Out from 24,445 vascular plant species 10,271 (42%) are endemic to Mexico.
Areas of endemism and phylogenetic endemism were associated with zones of
topographic complexity in the main mountain systems, in the deserts, and
in isolated dry zones. Every single locality that seasonal tropical dry
forests have been reported in Mexico was identified as an area of
endemism. Areas of significant phylogenetic diversity were the most
restricted and occurred in dry forests of the Trans-Mexican Volcanic Belt
and of the Sierra de Chiapas. The highest phylogenetic clustering
comprising neo- paleo- and super endemism was identified in the southern
extreme of Mexico. The flora of Mexico bears a signature of mixed neo- and
paleo-endemism, and areas of endemism occurred in dry forests. The
majority of vascular plant ineages diverged in the Miocene (5-20 million
of years ago) when arid environments expanded across the world. The
position of Mexico in the middle of two landmasses and the presence of
more than fifty percent of arid surface favored the establishment and
diversification of tropical lineages adapted to extreme seasonality and to
aridity that migrated from North America and from South America. Our
results identified areas of elevated species richness and phylogenetic
diversity and provide a foundation on which to propose conservation
efforts in Mexico.