Miniopterus aelleni
Encyclopedia
Miniopterus aelleni is a bat
in the genus Miniopterus
that occurs on Anjouan
in the Comoros
and in northern and western Madagascar
. It is a small, brown bat; its forearm length is 35 to 41 mm (1.4 to 1.6 in). The long tragus (a projection in the outer ear) has a broad base and a blunt to rounded tip. The uropatagium (tail membrane) is sparsely haired. The palate
is flat and there are distinct diastemata
(gaps) between the upper canines and premolar
s.
Populations of this species have historically been included in Miniopterus manavi, but evidence published in 2008 and 2009 indicates that M. manavi is actually a complex of five separate species, including the newly described M. aelleni. M. aelleni has been found in forests and caves in karstic
areas. Its distribution generally overlaps that of M. griveaudi
, also formerly included in M. manavi.
on Madagascar and the nearby Comoros
, including the small Miniopterus manavi with a broad distribution on both Madagascar and the Comoros. However, during the first decade of the 21st century, molecular studies have revealed that Miniopterus, a widespread genus in the Old World, is much more species-rich than previously thought. A 2008 study comparing sequences of the mitochondrial
cytochrome b
and D-loop
markers found two distinct, unrelated groups within the supposed M. manavi from the Comoros; both groups were also found on Madagascar. The next year, Steven Goodman
and colleagues revisited the group with more extensive sampling on Madagascar. They separated three species within the former "M. manavi": M. manavi itself in the Central Highlands
, M. griveaudi
(previously a subspecies
of M. manavi) on Anjouan
, Grande Comore
, and northern and western Madagascar, and the newly described Miniopterus aelleni on Anjouan and northern and western Madagascar. The specific name aelleni honors Prof. Villy Aellen of the Natural History Museum of Geneva
, who has done much research on African bats. Within M. aelleni, Goodman and colleagues found some differentiation (3.4% divergence in cytochrome b sequences) between individuals from Montagne d'Ambre in northern Madagascar and those from Anjouan and Ankarana, near Montagne d'Ambre; the cytochrome b divergence between M. aelleni and other Malagasy Miniopterus is 7 to 10%.
Later in 2009, Goodman and colleagues described two more species of M. manavi-like Malagasy Miniopterus: M. brachytragos
from northern Madagascar and M. mahafaliensis
from the southwest. On the basis of cytochrome b sequences, they found that M. aelleni was most closely related to a clade
of M. brachytragos, M. manavi, and another recently described Malagasy species, M. petersoni
. The five recognized species of M. manavi-like bats are not each others' closest relatives, but apparently acquired their similarities through convergent evolution
. At some places (for example, Namoroka
) four cryptic species of M. manavi-like bats, including M. aelleni, occur together.
Miniopterus aelleni is a small, brown Miniopterus species. The head may be slightly lighter in color than the body. Some hairs on the underparts have buff tips. Miniopterus griveaudi is similar in color, but M. manavi is darker and M. brachytragos and M. mahafaliensis are lighter. The tragus (a projection on the inner side of the outer ear) is long and has a broad base with a crest at the side, and ends in a blunt to slightly rounded tip. In M. manavi and M. griveaudi, in contrast, the base is narrower, in M. mahafaliensis, the sides of the tragus are parallel, and M. brachytragus has a short, blunt tragus sparsely covered with hair. The wing membrane is also brown, but the uropatagium is lighter. The wing membrane and uropatagium are attached to the upper leg at the same level, above the ankle. The uropatagium is sparsely covered with thin, but clearly visible hairs. In contrast, M. manavi, M. mahafaliensis, and M. brachytragos have densely covered uropatagia and that of M. griveaudi is almost naked. Individuals from Anjouan have significantly shorter hindfeet than those from Madagascar, but otherwise the two populations cannot be distinguished on the basis of external characteristics.
In the skull, the rostrum (front part) is short and line-shaped, but longer than in other manavi-like species. The central groove in the nasal depression is relatively narrow. The frontal bone
s are rounded and bear a well-developed sagittal crest
. Further back on the braincase, the lambdoid crest is also prominent. The middle part of the palate
is flat, as in M. manavi but unlike in M. brachytragos, M. griveaudi, and M. mahafaliensis, which have a curved palate. At the palate's back margin is a long, thin posterior palatal spine. Miniopterus aelleni has 36 teeth in the dental formula (two incisor
s, one canine, two premolar
s, and three molar
s in both upper toothrows and three incisors, one canine, three premolars, and three molars in the lower toothrows). As is characteristic of Miniopterus, the first upper premolar (P2; P1 and P3 are missing) is smaller and more simplified than the second (P4). There are clear diastemata
(gaps) between the upper canine (C1) and P2 and between P2 and P4, which are weaker or absent in M. griveaudi and M. manavi. Behind C1, the toothrows are about parallel, not divergent as in M. manavi. The third upper molar (M3) is more compressed than in M. manavi and M. griveaudi. In some measurements of the skull and teeth, Anjouan specimens are larger than those from Madagascar.
The animal has a karyotype
of 46 chromosome
s, with a total of 50 major arms on the autosome
s (non-sex chromosomes). The karyotype is conserved among species of Miniopterus; the number of chromosomes and arms is identical in M. aelleni, the Malagasy M. griveaudi and M. gleni
, and even the Asian M. fuliginosus.
areas; its distribution broadly overlaps that of M. griveaudi and the two have been found in the same roost sites on several occasions. On Anjouan, M. aelleni is less common than M. griveaudi; there, it is known from four specimens only, all collected in 2006. These come from two nearby sites: a rocky area near a river and a disturbed forest. These animals, collected in late November, were in reproductive condition, with two females pregnant and a third lactating. M. griveaudi were reproductively active at the same time, suggesting that the reproductive seasons of the two do not differ significantly. Although some ecological and behavioral data has been published on "Miniopterus manavi", the recognition of several cryptic species within this group, more than one of which may occur in any given locality, renders the association of these data with any of the individual species uncertain; however, species of Miniopterus generally feed on insects. Because M. aelleni is widespread and occurs in many protected area
s on Madagascar, Goodman and colleagues inferred that its conservation status
is secure.
Bat
Bats are mammals of the order Chiroptera "hand" and pteron "wing") whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight. By contrast, other mammals said to fly, such as flying squirrels, gliding possums, and colugos, glide rather than fly,...
in the genus Miniopterus
Miniopterus
Miniopterus is a genus of bats and the only genus of the family Miniopteridae. The genus was previously placed in its own subfamily, Miniopterinae, of the vesper bat family, but is now classified in its own family....
that occurs on Anjouan
Anjouan
Anjouan is an autonomous island, part of the Union of Comoros. The island is located in the Indian Ocean. Its capital is Mutsamudu and its population as of 2006 is about 277,500. The total area of the island is 424 sq. kilometers Anjouan (also known as Ndzuwani or Nzwani) is an autonomous island,...
in the Comoros
Comoros
The Comoros , officially the Union of the Comoros is an archipelago island nation in the Indian Ocean, located off the eastern coast of Africa, on the northern end of the Mozambique Channel, between northeastern Mozambique and northwestern Madagascar...
and in northern and western Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
. It is a small, brown bat; its forearm length is 35 to 41 mm (1.4 to 1.6 in). The long tragus (a projection in the outer ear) has a broad base and a blunt to rounded tip. The uropatagium (tail membrane) is sparsely haired. The palate
Palate
The palate is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but, in most other tetrapods, the oral and nasal cavities are not truly separate. The palate is divided into two parts, the anterior...
is flat and there are distinct diastemata
Diastema (dentistry)
Diastema is a space or gap between two teeth. Many species of mammals have diastemata as a normal feature, most commonly between the incisors and molars.-In humans:...
(gaps) between the upper canines and premolar
Premolar
The premolar teeth or bicuspids are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant, making eight premolars total in the mouth. They have at least two cusps. Premolars can be considered as a 'transitional tooth' during chewing, or...
s.
Populations of this species have historically been included in Miniopterus manavi, but evidence published in 2008 and 2009 indicates that M. manavi is actually a complex of five separate species, including the newly described M. aelleni. M. aelleni has been found in forests and caves in karstic
Karst topography
Karst topography is a geologic formation shaped by the dissolution of a layer or layers of soluble bedrock, usually carbonate rock such as limestone or dolomite, but has also been documented for weathering resistant rocks like quartzite given the right conditions.Due to subterranean drainage, there...
areas. Its distribution generally overlaps that of M. griveaudi
Miniopterus griveaudi
Miniopterus griveaudi is a bat in the genus Miniopterus found on Grande Comore and Anjouan in the Comoros and in northern and western Madagascar. First described in 1959 from Grande Comore as a subspecies of the mainland African M. minor, it was later placed with the Malagasy M. manavi...
, also formerly included in M. manavi.
Taxonomy
In a 1995 contribution to Faune de Madagascar on Malagasy bats, Randolph Peterson and colleagues listed four species of MiniopterusMiniopterus
Miniopterus is a genus of bats and the only genus of the family Miniopteridae. The genus was previously placed in its own subfamily, Miniopterinae, of the vesper bat family, but is now classified in its own family....
on Madagascar and the nearby Comoros
Comoros
The Comoros , officially the Union of the Comoros is an archipelago island nation in the Indian Ocean, located off the eastern coast of Africa, on the northern end of the Mozambique Channel, between northeastern Mozambique and northwestern Madagascar...
, including the small Miniopterus manavi with a broad distribution on both Madagascar and the Comoros. However, during the first decade of the 21st century, molecular studies have revealed that Miniopterus, a widespread genus in the Old World, is much more species-rich than previously thought. A 2008 study comparing sequences of the mitochondrial
Mitochondrial DNA
Mitochondrial DNA is the DNA located in organelles called mitochondria, structures within eukaryotic cells that convert the chemical energy from food into a form that cells can use, adenosine triphosphate...
cytochrome b
Cytochrome b
Cytochrome b/b6 is the main subunit of transmembrane cytochrome bc1 and b6f complexes. In addition, it commonly refers to a region of mtDNA used for population genetics and phylogenetics.- Function :...
and D-loop
D-loop
In molecular biology, a displacement loop or D-loop is a DNA structure where the two strands of a double-stranded DNA molecule are separated for a stretch and held apart by a third strand of DNA. The third strand has a base sequence which is complementary to one of the main strands and pairs with...
markers found two distinct, unrelated groups within the supposed M. manavi from the Comoros; both groups were also found on Madagascar. The next year, Steven Goodman
Steven Goodman
Steven Goodman is an American Conservation Biologist, and field biologist on staff in the Department of Zoology at the Field Museum of Natural History....
and colleagues revisited the group with more extensive sampling on Madagascar. They separated three species within the former "M. manavi": M. manavi itself in the Central Highlands
Central Highlands (Madagascar)
The Central Highlands, Central High Plateau, or Hauts-Plateaux are a mountainous biogeographical region in central Madagascar. They include the contiguous part of the island's interior above 800 m altitude...
, M. griveaudi
Miniopterus griveaudi
Miniopterus griveaudi is a bat in the genus Miniopterus found on Grande Comore and Anjouan in the Comoros and in northern and western Madagascar. First described in 1959 from Grande Comore as a subspecies of the mainland African M. minor, it was later placed with the Malagasy M. manavi...
(previously a subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
of M. manavi) on Anjouan
Anjouan
Anjouan is an autonomous island, part of the Union of Comoros. The island is located in the Indian Ocean. Its capital is Mutsamudu and its population as of 2006 is about 277,500. The total area of the island is 424 sq. kilometers Anjouan (also known as Ndzuwani or Nzwani) is an autonomous island,...
, Grande Comore
Grande Comore
Grande Comore is an island in the Indian Ocean off the coast of Africa. It is the largest island in the Comoros nation. Most of its population is of the Comorian ethnic group. Its population as of 2006 is about 316,600. The island's capital is Moroni, which is also the national capital...
, and northern and western Madagascar, and the newly described Miniopterus aelleni on Anjouan and northern and western Madagascar. The specific name aelleni honors Prof. Villy Aellen of the Natural History Museum of Geneva
Natural History Museum of Geneva
The Natural History Museum of Geneva is a natural history museum in Geneva, Switzerland....
, who has done much research on African bats. Within M. aelleni, Goodman and colleagues found some differentiation (3.4% divergence in cytochrome b sequences) between individuals from Montagne d'Ambre in northern Madagascar and those from Anjouan and Ankarana, near Montagne d'Ambre; the cytochrome b divergence between M. aelleni and other Malagasy Miniopterus is 7 to 10%.
Later in 2009, Goodman and colleagues described two more species of M. manavi-like Malagasy Miniopterus: M. brachytragos
Miniopterus brachytragos
Miniopterus brachytragos is a bat in the genus Miniopterus that occurs in northern and western Madagascar. Populations of this species have historically been included in Miniopterus manavi, but molecular data published in 2008 and 2009 indicate this supposed species in fact consists of five...
from northern Madagascar and M. mahafaliensis
Miniopterus mahafaliensis
Miniopterus mahafaliensis is a bat in the genus Miniopterus that occurs in southwestern Madagascar. Populations of this species have historically been included in Miniopterus manavi, but molecular data published in 2008 and 2009 indicate that this supposed species in fact consists of five separate...
from the southwest. On the basis of cytochrome b sequences, they found that M. aelleni was most closely related to a clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
of M. brachytragos, M. manavi, and another recently described Malagasy species, M. petersoni
Miniopterus petersoni
Miniopterus petersoni is a bat in the genus Miniopterus which occurs in southeast Madagascar. It was described by Steven M. Goodman et al. in 2008. While M. petersoni is similar to M. sororculus, the two species are not closely related to each other, and possess a number of differing external and...
. The five recognized species of M. manavi-like bats are not each others' closest relatives, but apparently acquired their similarities through convergent evolution
Convergent evolution
Convergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, both birds and bats do, and are capable of powered flight. The wings are...
. At some places (for example, Namoroka
Tsingy de Namoroka Strict Nature Reserve
Tsingy de Namoroka Strict Nature Reserve, also known as Namoroka National Park, is a strict nature reserve located in the northwestern part of Madagascar in the Mahajanga Province, specifically, the Soalala District.- Climate and geography :...
) four cryptic species of M. manavi-like bats, including M. aelleni, occur together.
Description
| Island | n | Total length | Tail | Hindfoot | Tragus | Ear | Forearm | Mass |
|---|---|---|---|---|---|---|---|---|
| Anjouan | 5 | 89.8 (88–91) | 43.4 (41–46) | 5.2 (5–6) | 6.0 (6–6) | 10.6 (10–11) | 38.2 (37–39) | 5.6 (4.7–6.5) |
| Madagascar | 12 | 90.7 (88–95) | 42.1 (40–45) | 6.1 (5–7) | 6.1 (5–8) | 11.1 (10–12) | 38.8 (35–41) | 4.6 (3.9–6.5) |
| All measurements are in the form "mean (minimum–maximum)" and are in millimeters, except mass in grams. | ||||||||
Miniopterus aelleni is a small, brown Miniopterus species. The head may be slightly lighter in color than the body. Some hairs on the underparts have buff tips. Miniopterus griveaudi is similar in color, but M. manavi is darker and M. brachytragos and M. mahafaliensis are lighter. The tragus (a projection on the inner side of the outer ear) is long and has a broad base with a crest at the side, and ends in a blunt to slightly rounded tip. In M. manavi and M. griveaudi, in contrast, the base is narrower, in M. mahafaliensis, the sides of the tragus are parallel, and M. brachytragus has a short, blunt tragus sparsely covered with hair. The wing membrane is also brown, but the uropatagium is lighter. The wing membrane and uropatagium are attached to the upper leg at the same level, above the ankle. The uropatagium is sparsely covered with thin, but clearly visible hairs. In contrast, M. manavi, M. mahafaliensis, and M. brachytragos have densely covered uropatagia and that of M. griveaudi is almost naked. Individuals from Anjouan have significantly shorter hindfeet than those from Madagascar, but otherwise the two populations cannot be distinguished on the basis of external characteristics.
In the skull, the rostrum (front part) is short and line-shaped, but longer than in other manavi-like species. The central groove in the nasal depression is relatively narrow. The frontal bone
Frontal bone
The frontal bone is a bone in the human skull that resembles a cockleshell in form, and consists of two portions:* a vertical portion, the squama frontalis, corresponding with the region of the forehead....
s are rounded and bear a well-developed sagittal crest
Sagittal crest
A sagittal crest is a ridge of bone running lengthwise along the midline of the top of the skull of many mammalian and reptilian skulls, among others....
. Further back on the braincase, the lambdoid crest is also prominent. The middle part of the palate
Palate
The palate is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but, in most other tetrapods, the oral and nasal cavities are not truly separate. The palate is divided into two parts, the anterior...
is flat, as in M. manavi but unlike in M. brachytragos, M. griveaudi, and M. mahafaliensis, which have a curved palate. At the palate's back margin is a long, thin posterior palatal spine. Miniopterus aelleni has 36 teeth in the dental formula (two incisor
Incisor
Incisors are the first kind of tooth in heterodont mammals. They are located in the premaxilla above and mandible below.-Function:...
s, one canine, two premolar
Premolar
The premolar teeth or bicuspids are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant, making eight premolars total in the mouth. They have at least two cusps. Premolars can be considered as a 'transitional tooth' during chewing, or...
s, and three molar
Molar (tooth)
Molars are the rearmost and most complicated kind of tooth in most mammals. In many mammals they grind food; hence the Latin name mola, "millstone"....
s in both upper toothrows and three incisors, one canine, three premolars, and three molars in the lower toothrows). As is characteristic of Miniopterus, the first upper premolar (P2; P1 and P3 are missing) is smaller and more simplified than the second (P4). There are clear diastemata
Diastema (dentistry)
Diastema is a space or gap between two teeth. Many species of mammals have diastemata as a normal feature, most commonly between the incisors and molars.-In humans:...
(gaps) between the upper canine (C1) and P2 and between P2 and P4, which are weaker or absent in M. griveaudi and M. manavi. Behind C1, the toothrows are about parallel, not divergent as in M. manavi. The third upper molar (M3) is more compressed than in M. manavi and M. griveaudi. In some measurements of the skull and teeth, Anjouan specimens are larger than those from Madagascar.
The animal has a karyotype
Karyotype
A karyotype is the number and appearance of chromosomes in the nucleus of an eukaryotic cell. The term is also used for the complete set of chromosomes in a species, or an individual organism.p28...
of 46 chromosome
Chromosome
A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...
s, with a total of 50 major arms on the autosome
Autosome
An autosome is a chromosome that is not a sex chromosome, or allosome; that is to say, there is an equal number of copies of the chromosome in males and females. For example, in humans, there are 22 pairs of autosomes. In addition to autosomes, there are sex chromosomes, to be specific: X and Y...
s (non-sex chromosomes). The karyotype is conserved among species of Miniopterus; the number of chromosomes and arms is identical in M. aelleni, the Malagasy M. griveaudi and M. gleni
Miniopterus gleni
Miniopterus gleni is a species of vesper bat in the Vespertilionidae family.It is found only in Madagascar.-Source:* Chiroptera Specialist Group 2000. . Downloaded on 19 July 2007....
, and even the Asian M. fuliginosus.
Distribution and ecology
Miniopterus aelleni is known to live from 4 to 225 m (10 to 740 ft) above sea level in northern and western Madagascar, at 1100 m (3610 ft) on Montagne d'Ambre, northern Madagascar, and from 220 to 690 m (720 to 2260 ft) on Anjouan in the nearby Comoros. On Madagascar, it has been recorded in forest and caves in karstKarst topography
Karst topography is a geologic formation shaped by the dissolution of a layer or layers of soluble bedrock, usually carbonate rock such as limestone or dolomite, but has also been documented for weathering resistant rocks like quartzite given the right conditions.Due to subterranean drainage, there...
areas; its distribution broadly overlaps that of M. griveaudi and the two have been found in the same roost sites on several occasions. On Anjouan, M. aelleni is less common than M. griveaudi; there, it is known from four specimens only, all collected in 2006. These come from two nearby sites: a rocky area near a river and a disturbed forest. These animals, collected in late November, were in reproductive condition, with two females pregnant and a third lactating. M. griveaudi were reproductively active at the same time, suggesting that the reproductive seasons of the two do not differ significantly. Although some ecological and behavioral data has been published on "Miniopterus manavi", the recognition of several cryptic species within this group, more than one of which may occur in any given locality, renders the association of these data with any of the individual species uncertain; however, species of Miniopterus generally feed on insects. Because M. aelleni is widespread and occurs in many protected area
Protected area
Protected areas are locations which receive protection because of their recognised natural, ecological and/or cultural values. There are several kinds of protected areas, which vary by level of protection depending on the enabling laws of each country or the regulations of the international...
s on Madagascar, Goodman and colleagues inferred that its conservation status
Conservation status
The conservation status of a group of organisms indicates whether the group is still extant and how likely the group is to become extinct in the near future...
is secure.
Literature cited
- Goodman, S.M., Maminirina, C.P., Weyeneth, N., Bradman, H.M., Christidis, L., Ruedi, M. and Appleton, B. 2009a. The use of molecular and morphological characters to resolve the taxonomic identity of cryptic species: the case of Miniopterus manavi (Chiroptera: Miniopteridae) (subscription required). Zoologica Scripta 38:339–363.
- Goodman, S.M., Maminirina, C.P., Bradman, H.M., Christidis, L. and Appleton, B. 2009b. The use of molecular phylogenetic and morphological tools to identify cryptic and paraphyletic species: Examples from the diminutive long-fingered bats (Chiroptera: Miniopteridae: Miniopterus) on Madagascar. American Museum Novitates 3669:1–34.
- Goodman, S.M., Weyeneth, N., Ibrahim, Y., Saïd, I. and Ruedi, M. 2010. A review of the bat fauna of the Comoro Archipelago (subscription required). Acta Chiropterologica 12(1):117–141.
- Nowak, R.M. 1994. Walker's Bats of the World. Baltimore: The Johns Hopkins University Press, 287 pp. ISBN 978-0-8018-4986-2
- Peterson, R.L., Eger, J.L. and Mitchell, L. 1995. Chiroptères. Faune de Madagascar 84:1–204 (in French).
- Richards, L.R., Rambau, R.V., Lamb, J.M., Taylor, P.J., Yang, F., Schoeman, M.C. and Goodman, S.M. 2010. Cross-species chromosome painting in bats from Madagascar: the contribution of Myzopodidae to revealing ancestral syntenies in Chiroptera (subscription required). Chromosome Research 18:635–653.
- Weyeneth, N., Goodman, S.M., Stanley, W.T. and Ruedi, M. 2008. The biogeography of Miniopterus bats (Chiroptera: Miniopteridae) from the Comoro Archipelago inferred from mitochondrial DNA (subscription required). Molecular Ecology 17:5205–5219.
External links
- Announcement of the discovery, with images, Les Musées de Genève, 24 June 2009 (in French)