Genus of bats
Miniopterus, known as the bent-winged or long winged bats, is the sole genus of the family Miniopteridae. They are small flying insectivorous mammals, micro-bats of the order Chiroptera, with wings over twice the length of the body. The genus had been placed in its own subfamily among the vespertilionid bats, as Miniopterinae, but is now classified as its own family.
Taxonomy
The genus was erected in 1837 by Charles L. Bonaparte. In the first systematic revision of the genus, published in a monograph of Miniopterus in 1858 by Robert F. Tomes, the author reallocated specimens and described new taxa.[3]
A new systematic arrangement was produced in an extensive study of poorly known chiropterans of the Indo-Austral region by James E. Hill in 1985, the greater resolution of the genus being determined by the British Museum of Natural History's acquisition of new series of specimens collected in Fiji, the New Hebrides and New Caledonia and the extensive collection made in New Guinea by ecologist Ben Gaskell on "Operation Drake".[4]
Recognised as a very widely dispersed group with distinct morphology, biology and genetic characters, the number of species and systematic arrangements varied between still contradictory treatments. The genus was nested within Vespertilionidae as Miniopterinae, one of five subfamilies, with doubts remaining on the relationships to sister groups. The position of the minopterines was determined as showing a phylogenetic relationship to either the vespertilionids or the molossids, these assumptions were compared and analysed in study using large data sets derived from multiple genetic indicators and statistical analysis to determine the basal relationships within the order Chiroptera. The authors of this 2007 study found support for elevation to the rank of family—as Miniopteridae—and that the vespertilionids and Miniopterus species formed a clade that had diverged from the molossids (free-tailed bats) at a period around 54–43 million years ago and from other species 49–38 mya.[2]
Morphology
Bent-winged bats are typically small (total length c. 10 cm, wingspans 30–35 cm, mass less than 20 g), with broad, short muzzles. The cranium is bulbous and taller than the snout, a feature shared with woolly bats and mouse-eared bats. This combination of features was likely present in the common ancestor of the vesper bats. They have two tiny, vestigial premolars between the upper canines and first large premolar. Unlike other bats, they lack a tendon-locking mechanism in their toes.
The common name bent-winged bat refers to their most obvious feature, the group's ability to fold back an exceptionally long third finger when the wings are folded. This finger gives the bats long, narrow wings that allows them to move at high speed in open environments and in some species to migrate over a distance of hundreds of kilometres.[5][2] The proportional length of the wing is around two and a half times that of the body and head.[6]
Research applications
In 2017, evidence of deltaretroviruses was found in the genome of the Miniopteridae.[7]
Deltaretroviruses only affect mammals, and this was the first evidence that they affected bat species.[7]
The presence of the deltaretrovirus in multiple Miniopterid species suggests that the virus was present in the family before speciation 20 million years ago.[7]
The evolutionary history of deltaretroviruses is important because they cause leukemia in humans.
Range
Bent-winged bats occur in southern Europe, across Africa and Madagascar, throughout Asia, and in Australia, Vanuatu and New Caledonia. One species, the common bent-wing bat, inhabits the whole of this range.[5] The group rapidly colonized much of this area in the last 15,000 years.
