Conservation Status and Red List Assessment of the Genus Verbascum (Scrophulariaceae) in the Arabian Peninsula

The aims of this study were to determine the geographical range and habitats of the Verbascum species in the Arabian Peninsula and to assess their conservation status at national, regional, and global levels by using the International Union for Conservation of Nature (IUCN) Red List categories and criteria. Verbascum is represented by 16 species with four varieties in the area of the study, and most of these species are endemic to Saudi Arabia, Yemen, Oman, and the United Arab Emirates (UAE). This study is based on an ecogeographic survey, which was conducted using herbaria collections, literature sources, and fieldwork. The findings showed that the genus is distributed in three main regions in the Arabian Peninsula, which include northern Saudi Arabia, the Asir and Yemen highlands, and the Hajar mountains in Oman and the UAE. In addition, most species of Verbascum in the region are at high risk of extinction. Nine taxa are threatened, four of which are assessed as Critically Endangered, four as Endangered, and one as Vulnerable. Furthermore, four species are assessed as Near Threatened, while another five species are assessed as of Least Concern. Threats to the Verbascum species in the region are overgrazing, suburban and agricultural expansion, climate change, invasive species, recreational activities, tourism, war, and civil unrest, leading to human intrusion and disturbances. Some important strategies for conserving and managing Verbascum species on the Arabian Peninsula are recommended here.