Free-tailed bats Temporal range: Late Eocene to recent | |
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Unidentified molossid: Note that the tail extends beyond the uropatagium | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Chiroptera |
Superfamily: | Vespertilionoidea |
Family: | Molossidae Gervais in de Castelnau, 1855 |
Type genus | |
Molossus Geoffroy, 1805 | |
Subfamilies | |
The Molossidae, or free-tailed bats, are a family of bats within the order Chiroptera. [1] The Molossidae is the fourth-largest family of bats, containing about 110 species as of 2012. [2] 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. [3] Their strong flying form allows them to fly 60 miles per hour using tail winds and at altitudes over 10,000 feet. [3] This makes them unique among bats, as they are the only bat family that withstands the elevation. They are widespread, being found on every continent except Antarctica. They are typically found in caves, abandoned mines, or tunnels. [3]
The family's scientific name comes from the type genus Molossus , which in turn is from the Molossus breed of dogs. [4]
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.[ citation needed ]
Another common name for some members of this group, and indeed a few species from other families, is mastiff bat. The western mastiff bat (Eumops perotis), a large species from the southwestern United States and Mexico with wings over 0.5 m (1.6 ft) across, is perhaps one of the best known with this name. They are widespread, being found on every continent except Antarctica.[ citation needed ]
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. [5] The dental formula of free-tailed bats varies between species: 1.1.1-2.2-31-3.1.2.3
Free-tailed bats are usually grey, brown, or black in color, with some exceptions. They range from 4 to 12 cm (1.6 to 4.7 in) in length, excluding the tail, and can weigh from 8 to 220 g (0.28 to 7.76 oz), 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. [5]
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 . [6]
Internal relationship of Molossinae [2] |
A 2012 study attempted to show the relationships of genera within the subfamily Molossinae (the other subfamily of Molossidae, Tomopeatinae, only contains the blunt-eared bat). [2] 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 (left), 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 (containing Molossus, Eumops, Molossops, Cynomops, Neoplatymops, Nyctinomops, and Promops); Tadarini (containing Tadarida, Chaerephon, Mops, Platymops, Sauromys, Myopterus, and Otomops); Cheiromelini (containing Cheiromeles); and Mormopterini (containing Mormopterus) [2]
The 18 genera contain about 100 species:
FAMILY MOLOSSIDAE
Mormopterus is a genus of molossid microchiropterans, small flying mammals referred to as free-tailed bats. The genus has been the subject of several revisions, and the diversity of taxa centred on Australia were separated to a new genus Ozimops, and two monotypic genera, Setirostris and Micronomus. The species of Mormopterus, in this stricter sense, are only found in areas outside of Australia and West Papua.
The name mastiff bat is applied to certain species of the bat family Molossidae or so called free-tailed bats. It is usually applied specifically to the following genera:
Wagner's bonneted bat or Wagner's mastiff bat, is a species of bat in the family Molossidae. It is found in the Americas from Argentina and Peru north to Mexico, and Cuba. Populations in Florida in the United States are now recognized as the Florida bonneted bat
The dwarf dog-faced bat is a species of free-tailed bat from South America. It is found in Argentina, Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, Paraguay and Uruguay, typically at lower elevations. It is one of two species in the genus Molossops, the other being the rufous dog-faced bat. Three subspecies are often recognized, though mammalogist Judith Eger considers it monotypic with no subspecies. It is a small free-tailed bat, with a forearm length of 28.9–32.5 mm (1.14–1.28 in) and a weight of 5–8 g (0.18–0.28 oz); males are larger than females. It is brown, with paler belly fur and darker back fur. Its wings are unusual for a free-tailed bat, with exceptionally broad wingtips. Additionally, it has low wing loading, meaning that it has a large wing surface area relative to its body weight. Therefore, it flies more similarly to a vesper bat than to other species in its own family. As it forages at night for its insect prey, including moths, beetles, and others, it uses two kinds of frequency-modulated echolocation calls: one type is to navigate in open areas and to search for prey, while the other type is used for navigating in cluttered areas or while approaching a prey item.
Eumops is a genus of bats in the family Molossidae. A total of 17 species of this genus have been described. The name "Eumops" comes from the Greek prefix "Eu-", meaning "good" or "true," and the Malayan word "mops," which means bat.
Mops is a genus of bats in the family Molossidae. Molecular sequence data indicates that Mops and Chaerephon are not monophyletic taxa. However, the grouping of Chaerephon and Mops was found to be monophyletic when excluding C. jobimena.
Eumops ferox, the fierce bonneted bat or the chestnut mastiff bat, is a species of free-tailed bat found in the Caribbean and Mexico. Until recently, it was synonymous with Wagner's bonneted bat.
The name of the [free-tailed bats] family is derived from the Greek molossus, a kind of dog used by Greek shepherds in ancient times