Examining all the native flowering plants and ferns (3500-4000 species), as well as major crop and amenity plants of economic importance, the Flora covers Saudi Arabia, Yemen, Oman, the United Arab Emirates, Qatar, Bahrain and Kuwait.

The present flora thoroughly covers the bryophytes of the Arabian Peninsula and Socotra island, with keys to all species, notes on the occurrence of the species in the different countries (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, United Arab Emirates, Yemen) and distribution maps. In contrast, the arid and semi-arid parts of inner Arabia (winter rainfall area) are dominated by drought-adapted and drought-tolerant taxa of probably xerothermic-Pangaean and circum-Tethyan origin. They show a number of xeromorphic adaptations (xeropottioid and xerothalloid life syndrome) for life under desert conditions. The phytogeographical analysis of the bryoflora, as well as the distribution of thalloid and leafy liverworts, respectively acrocarpous and pleurocarpous mosses, demonstrate that there is a clear phytochorial border across the Peninsula, frequently correlated with climatic conditions (winter rainfall/summer rainfall line).

Although the unique flora of the Socotra Archipelago with its high degree of endemism has received much attention recently, little information is available on the vegetation and related ecological aspects. Based on their extensive field experience of the region, the authors have assimilated a vast amount of knowledge to produce this book, which gives a detailed insight into the plant ecology of Socotra, designated as a World Heritage Site by UNESCO in 2008. The book is divided into seven chapters. After a brief introduction and overviews of important abiotic features, various aspects of the vascular flora are presented in Chapter 4, together with accounts of the bryophyte and lichen flora. Ecology and adaptive strategies of the plants are dealt with in Chapter 5, and Chapter 6 gives a concise description of the main vegetation units. Finally, important management issues of the vegetation are discussed, an essential topic to ensure preservation of the natural heritage of the archipelago.