The Arecaceae are a botanical family of perennial climbers, shrubs, acaules and trees commonly known as palm trees (owing to historical usage, the family is alternatively called Palmae). They are flowering plants, a family in the monocot order Arecales. Currently 181 genera with around 2600 species are known, most of them restricted to tropical, subtropical, and warm temperate climates. Most palms are distinguished by their large, compound, evergreen leaves arranged at the top of an unbranched stem. However, palms exhibit an enormous diversity in physical characteristics and inhabit nearly every type of habitat within their range, from rainforests to deserts.