There are six floral kingdoms formed by the grouping of related species and families in different regions of the world.
The distribution of plants is affected and controlled by a variety of factors such as climate, edaphic, biotic, physical, tectonic, and fire factors, dispersion of plants, as well as human interference.
Areas, where plants belonging to certain families are widely spread, are called floral regions.
Botanist Ronald Good grouped six major floral kingdoms based on their worldwide distribution.
The Holarctic floral kingdom, the largest one, is home to 60 endemic families. It encompasses all non-tropical parts of Europe and Asia, Africa, the northern Sahara, North America, and the southern Mexican desert region.
The Neotropical floral kingdom covers all but the extreme southern tip and the southwestern strip of South America, Central America, Mexico, excluding the dry north and center, and beyond to the West Indies and the southern tip of Florida. It has 47 endemic families and 3,000 endemic species.
The Australian floral kingdom covers Australia, its neighboring islands, and surrounding seas and oceans. There are 19 endemic families and 500 endemic species in the kingdom.
The Capensic floral kingdom, with 11 endemic families and 500 endemic species, stretches over the southern province of South Africa.
The Paleotropical floral kingdom stretches over the greater parts of Africa, West Asia, South Asia, China, and the countries of South Asia and Southeast Asia. There is great variation in floral species in the different parts of this zone. It has 40 endemic families and 2,000 endemic species.
The Antarctic floral kingdom stretches in the higher latitudes of the southern hemisphere, including the Desert of Patagonia, southern parts of southern Chile, and New Zealand. It has 50 endemic species./aa