Free-tailed bat

Free-tailed bat
The Molossidae, or free-tailed bats, are a family of bats within the order Chiroptera.
The Molossidae is 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 form allows them to fly 60 miles per hour using tail winds and at altitudes over 10,000 feet. 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.
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 (Eumops perotis), 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 (the other subfamily of Molossidae, Tomopeatinae, only contains the blunt-eared bat).
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)
Classification
The 18 genera contain about 100 species:
FAMILY MOLOSSIDAE
Genus †Cuvierimops
Genus †Nyctinomus
Genus †Potamops
Genus †Rhizomops
Genus †Wallia
Subfamily Molossinae
Genus Chaerephon – lesser mastiff bats
Duke of Abruzzi's free-tailed bat, Chaerephon aloysiisabaudiae
Ansorge's free-tailed bat, Chaerephon ansorgei
Gland-tailed free-tailed bat, Chaerephon bemmeleni
Spotted free-tailed bat, Chaerephon bivittata
Fijian mastiff bat, Chaerephon bregullae
Chapin's free-tailed bat, Chaerephon chapini
Gallagher's free-tailed bat, Chaerephon gallagheri
Northern freetail bat, Chaerephon jobensis
Black and red free-tailed bat, Chaerephon jobimena
Northern free-tailed bat, Chaerephon johorensis
Grandidier's free-tailed bat, Chaerephon leucogaster
Lappet-eared free-tailed bat, Chaerephon major
Nigerian free-tailed bat, Chaerephon nigeriae
Wrinkle-lipped free-tailed bat, Chaerephon plicata
Little free-tailed bat, Chaerephon pumilus
Russet free-tailed bat, Chaerephon russata
Solomons mastiff bat, Chaerephon solomonis
São Tomé free-tailed bat, Chaerephon tomensis
Genus Cheiromeles – naked bats, or hairless bats
Greater naked bat, Cheiromeles torquatus
Lesser naked bat, Cheiromeles parvidens
Genus Cynomops
Cinnamon dog-faced bat, Cynomops abrasus
Freeman's dog-faced bat, Cynomops freemani
Greenhall's dog-faced bat, Cynomops greenhalli
Mexican dog-faced bat, Cynomops mexicanus
Para dog-faced bat, Cynomops paranus
Southern dog-faced bat, Cynomops planirostris
Genus Eumops – mastiff bats, or bonneted bats
Black bonneted bat, Eumops auripendulus
Dwarf bonneted bat, Eumops bonariensis
Big bonneted bat, Eumops dabbenei
Fierce bonneted bat, Eumops ferox
Florida bonneted bat, Eumops floridanus
Wagner's bonneted bat, Eumops glaucinus
Sanborn's bonneted bat, Eumops hansae
Guianan bonneted bat, Eumops maurus
Patagonian bonneted bat, Eumops patagonicus
Western mastiff bat, Eumops perotis
Colombian bonneted bat, Eumops trumbulli
Underwood's bonneted bat, Eumops underwoodi
Wilson's bonneted bat, Eumops wilsoni
Genus Mormopterus
Subgenus Mormopterus
Natal free-tailed bat, Mormopterus acetabulosus
Moutou's free-tailed bat, Mormopterus francoismoutoui
Sumatran mastiff bat, Mormopterus doriae
Peters's wrinkle-lipped bat, Mormopterus jugularis
Kalinowski's mastiff bat, Mormopterus kalinowskii
Little goblin bat, Mormopterus minutus
Incan little mastiff bat, Mormopterus phrudus
Subgenus Micronomus
Beccari's mastiff bat, Mormopterus beccarii
Bristle-faced free-tailed bat, Mormopterus eleryi
Loria's mastiff bat, Mormopterus loriae
East-coast free-tailed bat, Mormopterus norfolkensis
Southern free-tailed bat, Mormopterus planiceps
Genus Molossops – broad-faced bats
Equatorial dog-faced bat, Molossops (Cabreramops) aequatorianus
Rufous dog-faced bat, Molossops neglectus
Dwarf dog-faced bat, Molossops temminckii
Genus Molossus – velvety free-tailed bats
Alvarez's mastiff bat, Molossus alvarezi
Aztec mastiff bat, Molossus aztecus
Barnes' mastiff bat, Molossus barnesi
Coiban mastiff bat, Molossus coibensis
Bonda mastiff bat, Molossus currentium
Velvety free-tailed bat, Molossus molossus
Miller's mastiff bat, Molossus pretiosus
Black mastiff bat, Molossus rufus
Sinaloan mastiff bat, Molossus sinaloae
Genus Mops – greater mastiff bats
Subgenus Xiphonycteris
Spurrell's free-tailed bat, Mops spurrelli
Dwarf free-tailed bat, Mops nanulus
Peterson's free-tailed bat, Mops petersoni
Sierra Leone free-tailed bat, Mops brachypterus
Bakari's free-tailed bat, Mops bakarii
Railer bat, Mops thersites
Subgenus Mops
Angolan free-tailed bat, Mops condylurus
White-bellied free-tailed bat, Mops niveiventer
Mongalla free-tailed bat, Mops demonstrator
Malayan free-tailed bat, Mops mops
Sulawesi free-tailed bat, Mops sarasinorum
Trevor's free-tailed bat, Mops trevori
Medje free-tailed bat, Mops congicus
Midas free-tailed bat, Mops midas
Niangara free-tailed bat, Mops niangarae
Medje free-tailed bat, Mops congicus
Malagasy white-bellied free-tailed bat, Mops leucostigma
Genus Myopterus
Daubenton's free-tailed bat, Myopterus daubentonii
Bini free-tailed bat, Myopterus whitleyi
Genus Nyctinomops – New World free-tailed bats
Peale's free-tailed bat, Nyctinomops aurispinosus
Pocketed free-tailed bat, Nyctinomops femorosaccus
Broad-eared bat, Nyctinomops laticaudatus
Big free-tailed bat, Nyctinomops macrotis
Genus Neoplatymops
Mato Grosso dog-faced bat, Neoplatymops mattogrossensis
Genus Otomops – big-eared free-tailed bats
Javan mastiff bat, Otomops formosus
Johnstone's mastiff bat, Otomops johnstonei
Madagascar free-tailed bat, Otomops madagascariensis
Large-eared free-tailed bat, Otomops martiensseni
Big-eared mastiff bat, Otomops papuensis
Mantled mastiff bat, Otomops secundus
Wroughton's free-tailed bat, Otomops wroughtoni
Genus Platymops
Peters's flat-headed bat, Platymops setiger
Genus Promops – domed-palate mastiff bats
Big crested mastiff bat, Promops centralis
Brown mastiff bat, Promops nasutus
Genus Sauromys
Roberts's flat-headed bat, Sauromys petrophilus
Genus Tadarida – free-tailed bats
Egyptian free-tailed bat, Tadarida aegyptiaca
Mexican free-tailed bat, Tadarida brasiliensis
Madagascan large free-tailed bat, Tadarida fulminans
East Asian free-tailed bat, Tadarida insignis
La Touche's free-tailed bat, Tadarida latouchei
Kenyan big-eared free-tailed bat, Tadarida lobata
European free-tailed bat, Tadarida teniotis
African giant free-tailed bat, Tadarida ventralis
Genus Austronomus
White-striped free-tailed bat, Austronomus australis
New Guinea free-tailed bat, Austronomus kuboriensis
Subfamily Tomopeatinae
Genus Tomopeas
Blunt-eared bat, Tomopeas ravus
References
Further reading
Extant Eocene first appearances
Taxa named by Paul Gervais