A total of 12,382 climbers from 143 families and 1,415 genera are recorded in the Old World, including 57 families with climbers only in the Old World (e.g. Actinidiaceae). As for Eurasia and North Africa, 6,659 climbers were documented to be native, belonging to 101 families and 809 genera. About 30.8 % of them are herbaceous and 69.2 % are somewhat woody. Only one family, but 285 genera (35.2 %) and 5,283 species (79.3 %) are climber-endemic to Eurasia and North Africa. Leguminosae and Apocynaceae are the two largest families with climbers, followed by Convolvulaceae, Vitaceae, Cucurbitaceae and Rubiaceae. The most climber-abundant families in Eurasia and North Africa are similar to Sub-Saharan Africa, except Ranunculaceae, Rosaceae and Arecaceae. The Bignoniaceae, Araceae and Compositae are less prevalent in Eurasia and North Africa compared with the Americas, while Ranunculaceae, Rosaceae, Arecaceae and Annonaceae stand out. The study area was divided into 19 regions and 211 districts. Diversity and geographical distribution of climbing plants in these regions and districts are discussed. South-east Asia, South China, South Asia and the Himalayas are the top four climber-abundant regions and each have more than 1,000 climbers and significantly higher than the rest regions. The proportion of climbing plants in the spermatophyte flora declined from 20 % in Malay Peninsula to less than 2 % in Sahara, Asian plateaus and the northern Eurasia.
- West Malay Archipelago