Richness, Endemism and Floristic Affinities of the Palms of Mexico

The Arecaceae family is ecologically, ethnobotanically and floristically important in Mexico; however, an updated review is required. Here, we investigate the species richness, floristic geographic affinities, and conservation status of the native Mexican palm flora. We constructed a database of the distribution of species by state, performed a cluster analysis, and identified threatened species according to the Mexican red list (NOM-ECOL-059). We found that Mexico hosts 3 subfamilies, 10 tribes, 21 genera, and 99 species of palms (37.7% of which are endemic). Compred to other families, Arecaceae presents intermediate diversity, in which 62.7% of the species are considerd rare. Arecaceae is one of the most threatened families in Mexico. Five large regions are segregated according to species composition (similarity < 8%). Western Mexico exclusively presents Nearctic elements; the tribes Chamaedoreeae, Sabaleae, and Trachycarpeae are the most diversified. The genera Brahea, Sabal and Washingtonia prefer calcareous substrates, and are responsible for the distinctiveness of the Mexican palm flora. The species assemblage has South American and Laurasian origins. The remarkable species richness of Mexican palms is due to the speciation of these Chamaedoreeae, Sabaleae and Trachycarpeae tribes. The greatest species richness is presented in the South-Southeast region of the country (CAM, Q.ROO, YUC, CHIS, OAX, VER, TAB, PUE). Given the importance of palms for humans and the threatened status of the family in general, a more comprehensive analysis of the taxonomy and systematics of the family is required in Mexico, as well as to motivate the continued scientific study of these key plants. Specifically, more studies are required of the ecology, conservation, and sustainable management of the family in the southern states such as Chiapas, Oaxaca and Veracruz, which present the highest species richness, but also face rapid anthropogenic transformation.

Automated summary

The Arecaceae family is ecologically, ethnobotanically and floristically important in Mexico, but an updated review is required. Mexico hosts 99 species of palms, with 37.7% being endemic. Arecaceae presents intermediate diversity in Mexico, with 62.7% of the species considered rare. Arecaceae is one of the most threatened families in the country.