Woods from Miocene sediments in Panotla, Tlaxcala, Mexico

The extant regional vegetation of Panotla, Tlaxcala, Mexico, is the result of its geography, mainly due to the buildup of the Mexican Trans-volcanic Belt. Before this volcanic belt originated, palaeobotanical evidence suggests that topographic, palaeoclimatic and ecological conditions were different, allowing the establishment of an evergreen tropical forest represented by plants similar to Terminalia, Cedrela and cf. Hypodaphnys, which together suggest the presence of a warm-humid (tropical) climate in a region not higher than 900 masl. In contrast, today Panotla is located at an altitude that varies from 2100 to 2300 masl, has a temperate sub-humid climate, with annual precipitation of 1650 mm, maximum annual temperature of 24.3 °C, and its vegetation is composed of a white pine (Pinus pseudostrobus Lindol.), oak (Quercus spp.) and white cedar (Cupressus benthamii Endl.). Geological and palaeobiological evidence suggests an active volcanic and tectonic scenario that influenced plant evolution by shifting climatic conditions from high temperature-humid to high temperature-dry, selecting the plant communities in the region through time, supporting the change from a tropical rain forest to a xeric vegetation.