Floristic Diversity and Phytogeography of JABAL Fayfa: A Subtropical Dry Zone, South-West Saudi Arabia

The present study surveyed the flora of the Jebel Fayfa region, South-West Saudi Arabia to analyze four elements of the vegetation: floristic diversity, life form, lifespan, and phytogeographical affinities. A total of 341 species of vascular plants were recorded belonging to 240 genera in 70 families, of which 101 species distributed among 40 families were considered as new additions to the flora of Jabal Fayfa. Six species are considered endemic to the study area while 27 are endangered. The most represented families were Fabaceae, Asteraceae, and Poaceae. The flora of Jabal Fayfa exhibited a high degree of monotypism. A total of 20 families (28.57%) were represented by a single species, and 180 genera (75.00%) were monotypic. The recorded flora consists of 70.09% perennials and 29.91% annuals. Phanerophytes and therophytes were the most frequent lifeforms. Phytogeographical analysis revealed that the biregional elements of the Saharo-Arabian/Sudano-Zambezian chorotype are the most dominant chorotypes (35.48%), forming two-thirds of the floristic structure in Jabal Fayfa. The new additions to the local flora of the region indicate that the Jabal Fayfa region and the country need further thorough botanical exploration and documentation which would help in adding several species to the flora of Saudi Arabia.