Free-tailed bat


The Molossidae, or free-tailed bats, are a family of bats within the order Chiroptera.
The Molossidae comprise the fourth-largest family of bats, containing about 110 species as of 2012. They are generally quite robust, and consist of many strong-flying forms with relatively long and narrow wings with wrinkled lips shared through their genus. Their strong flying forms allows them to fly 60 miles per hour using tail winds and at altitudes over 10,000 feet. This makes them unique compared to any other bat as they are the only bat who withstand the elevation. They are widespread, being found on every continent except Antarctica. They are typically found in some in caves, abandoned mines, or tunnels.

Common ancestry

The family's scientific name comes from the type genus Molossus, which in turn is from the Molossus breed of dogs.
The family's common name is derived from a length of "free" tail, projecting beyond the end of the uropatagium—the membrane that connects the base of the tail to the hind legs.
Another common name for some members of this group, and indeed a few species from other families, is mastiff bat. The western mastiff bat, a large species from the southwestern United States and Mexico with wings over across, is perhaps one of the best known with this name. They are widespread, being found on every continent except Antarctica.

Anatomy

The tail is usually best seen when resting. A special ring of cartilage slides up or down the tail vertebrae by muscular action to stretch or retract the tail membrane. This gives many species a degree of fine tuning in their flight maneuvers to rival their day-flying ecological equivalents, such as swifts, swallows, and martins. As a result, these animals include the fastest-flying of all bat species among their number. The dental formula of free-tailed bats varies between species:
Free-tailed bats are usually grey, brown, or black in color, with some exceptions. They range from in length, excluding the tail, and can weigh from, depending on species. They are insectivorous, and catch their food on the wing. While some species roost in small groups in hollow trees or rocky crevices, some cave-dwelling species form vast colonies of up to 50 million individuals.
Molecular sequence data support the monophyly of the Molossidae as a whole, but not that of many of its genera, such as Chaerephon, Mops, Mormopterus, and Tadarida. The grouping of Chaerephon minus C. jobimena plus Mops was found to be monophyletic, as was Otomops.

Systematics

A 2012 study attempted to show the relationships of genera within the subfamily Molossinae.
This study used genetic data to create a phylogeny, which contrasted from previous phylogenies constructed using morphological data.
Traits that were previously used to group species, such as having a flat skull, were shown to have no relation to evolutionary relationship, meaning that flat-headedness evolved multiple times within the family.
Of the 16 genera of Molossinae, 15 were used to create the phylogeny, with researchers unable to include Peters's flat-headed bat, the only member of Platymops.
The results of this study showed that Chaerephon is paraphyletic, forming a clade with Mops.
There was strong support for Old World and New World clades.
While the genus Tadarida has one New World species, the Mexican free-tailed bat, the genus itself has its origins in the Old World.
The most recent common ancestor of Tadarida with New World genera was 29 million years ago.
Several tribes have been proposed within the Molossinae.
Ammerman et al. proposed Molossini ; Tadarini ; Cheiromelini ; and Mormopterini

Classification

The 18 genera contain about 100 species:
FAMILY MOLOSSIDAE