Diversidad de plantas vasculares de la Provincia Fisiográfica de la Sierra Madre Oriental, México

Background: The Sierra Madre Oriental is a Physiographic Province located in northeastern Mexico and has distinctive geological, climatic, and edaphic characteristics. The fora in this region has not been inventoried as a whole. Question: What is the foristic diversity of the Physiographic Province of the Sierra Madre Oriental? What is the geographic affnity of its genera? Site and years of study: The Physiographic province of the Sierra Madre Oriental. The work was conducted from August 2012 to December 2020. Methods: An exhaustive search for information was carried out using various sources such as herbaria, databases, foristic works, and monographs. To each species was registered the type of vegetation, geographic affnity and endemism. Results: A total of 6,981 species are registered; 1,542 are endemic to the Sierra Madre Oriental. The most diversity families were Asteraceae (1,000 species), Fabaceae (495), Cactaceae (365) and Poaceae (328). The temperate forests housed the greatest number of species (2,906). Querétaro was the richest state (2,803), followed by Coahuila with (2,710) and Nuevo León (2,406). The greatest number of genera of the species in the Sierra Madre Oriental have geographical boreal affnity (2,742), followed by species with tropical affnity (2,020), endemics to Mexico (1,227), with a cosmopolitan distribution (803), and from the deserts of the world (189). Conclusions: The Sierra Madre Oriental is home to more than a quarter of the vascular fora and 13 % of the endemic plants from Mexico. The area combines genera of different geographic affnities, mostly boreal, followed by tropical and endemic.