There are approximately 1100 known species (view a list) of bats in the world. Bats are mammals (class Mammalia) from the order Chiroptera which means “winged hands” in Latin. Under Chiroptera bats are divided into two suborders; the Megachiroptera and Microchiroptera.
The sub-order Megachiroptera is made up of the larger, fruit-eating bats of the Old World (Africa, Asia, Australia and the Pacific islands). These bats are generally recognized by their large size, large eyes, long-snouts, and wings designed to wrap around their bodies while they are roosting. The flying fox is an example of a Megachiroptera. These bats generally lack the ability to echolocate.
The Microchiroptera is the more diverse of the two sub-orders. These bats are generally smaller, insectivorous bats found throughout the world (except for the coldest regions). These species have highly developed echolocation systems to locate insect prey in the dark as well as to navigate roosting areas. Due to the development of echolocation, these bats often have strange facial features including bizarre shaped noses or mouths for making and directing the vocalizations used in echolocation and large ears to receive the returning echoes. These bats, although they have good eyesight, generally rely less on their vision and therefore have smaller eyes. While most species in this sub-order feed on insects, some have adapted different diets that include pollen, fruit, even fish and blood.
These 18 distinct families are made up of approximately 1100 species of bats found throughout the world. Generally speaking, tropical regions are home to a greater diversity of bats than temperate regions. For example Papua New Guinea, a country with an area just slightly larger than California has 91 known species of bats while United States has just 47. Canada has 20 known species of bat, while Mexico has 137.
These 1100 species of bat represent an incredible diversity in adaptations!
For more information in the current estimate of bat species view this article by Bat Conservation International.