Geographic distribution and conservation of Cactaceae from Tamaulipas Mexico

An inventory of the species of Cactaceae from Tamaulipas, Mexico was carried out. The study area was divided into 48 squares of 30 min of latitude and 30 min of longitude. Collections were made at 60 sampling sites distributed over an area extending in to the bordering states of San Luis Potosi , Nuevo Leon, Veracruz and Texas ( USA). Species diversity per squares and their geographic distribution range were obtained. Results showed a diversity of 120 species and 53 subspecies, of total 49 are considered as endangered by the CITES, IUCN, and SEMARNAT. The genera most represented were Mammillaria, Coryphantha, Echinocereus and Opuntia. Index of Geographical Expansion ( IGE) was calculated for each species. Highest diversity per squares as well as the IGE for each species was found at square 66 ( Jaumave) IGE = 52%, 72 ( Tanque Blanco) IGE = 22% and 59 ( Cd. Victoria) IGE = 7%. It was for these sites that had the highest number of endemic taxa and thus are recommended as priority sites for conservation. This information may help establish natural protected areas by the government of the State of Tamaulipas.