Voalavo
Encyclopedia
Voalavo is a genus
of rodent
in the subfamily Nesomyinae
, found only in Madagascar
. Two species are known, both of which occur in mountain forest above 1250 m (4100 ft) altitude; Voalavo gymnocaudus lives in northern Madagascar and Voalavo antsahabensis is restricted to a small area in the central part of the island. The genus was discovered in 1994 and formally described in 1998. Within Nesomyinae, it is most closely related to the genus Eliurus
, and DNA sequence
data suggest that the current definitions of these two genera need to be changed.
Species of Voalavo are small, gray, mouse-like rodents, among the smallest nesomyines. They lack the distinctive tuft of long hairs on the tail that is characteristic of Eliurus. The tail is long and females have six mammae. In Voalavo, there are two glands on the chest (absent in Eliurus) that produce a sweet-smelling musk
in breeding males. In the skull, the facial skeleton is long and the braincase is smooth. The incisive foramina
(openings in the front part of the palate) are long and the bony palate itself is smooth. The molars
are somewhat hypsodont
(high-crowned), though less so than in Eliurus, and the third molars are reduced in size and complexity.
, with a single species, the type
Voalavo gymnocaudus, restricted to the Northern Highlands
of Madagascar. The generic name Voalavo is a Malagasy word for "rodent". A second species, Voalavo antsahabensis, was named by Goodman and colleagues in 2005 from the region of Anjozorobe
in the Central Highlands
. The two Voalavo species are closely related and quite similar, but differ in various subtle morphological characters (mainly measurements) and by 10% in the sequence
of the mitochondrial
gene cytochrome b
.
Voalavo is part of the subfamily Nesomyinae
, which includes nine genera that are all restricted to Madagascar. Before the discoveries of Monticolomys
(published in 1996) and Voalavo (1998), all of the known genera within Nesomyinae were quite distinct from each other, so much so that phylogenetic relationships among them long remained obscure. Like Monticolomys (closely related to Macrotarsomys
), however, Voalavo shows clear similarities to another nesomyine genus, Eliurus
. In their description of Voalavo, Carleton and Goodman argued that, although closely related, Eliurus and Voalavo form separate monophyletic groups; but a 1999 molecular phylogenetic study by Sharon Jansa and colleagues, who compared cytochrome b sequences among nesomyines and other rodents, found that Voalavo gymnocaudus was more closely related to Eliurus grandidieri than to other species of Eliurus. This finding called into question the separate generic status of Voalavo. However, tissue samples of Eliurus petteri
, a species that is thought to be closely related to E. grandidieri, were not available, so this species could not be included in the study. Data from nuclear
genes also supports the relationship between V. gymnocaudus and E. grandidieri, but E. petteri remains genetically unstudied and the taxonomic
issue has not been resolved.
Molecular phylogenetic analysis of nuclear DNA supports a close relationship between Eliurus, Voalavo, and two other nesomyine genera, Gymnuromys and Brachytarsomys
. These genera are more distantly related to the other nesomyine genera and even more distantly to the other subfamilies of the family Nesomyidae
, which occur in mainland Africa.
Voalavo is a small rodent resembling a mouse with gray fur. Species of the genus are among the smallest known nesomyines, close in size only to Monticolomys koopmani. In terms of external morphology, Voalavo is barely different from Eliurus; fur coloration patterns, general morphology of the feet, and number of mammae
(six) are all the same in both genera. However, all species of Eliurus have a pronounced tuft of elongated hairs at the tip of the tail, a feature that is absent in Voalavo, although the latter does have slightly longer hairs near the tip. The tail is longer than the head and body. Relative tail length in V. gymnocaudus (136% of head and body length) is comparable to that of the longest-tailed species of Eliurus, E. grandidieri and E. petteri, but V. antsahabensis has a somewhat shorter tail. Furthermore, the pads of the feet are larger in Eliurus, and specifically, the thenar pad (located at the middle of the tarsus
) is circular and fairly small in Voalavo, but longer and larger in Eliurus. On the chest, Voalavo species have a gland that produces a sweet-swelling musk in breeding males; this gland is absent in Eliurus. Unlike all other nesomyines but Brachyuromys
, Voalavo lacks an entepicondylar foramen
, an opening on the humerus
(upper arm bone).
The skull of Voalavo also resembles that of Eliurus, with a long facial skeleton, a hourglass-shaped interorbital region
(between the eyes), and a smooth interorbital region and braincase, without ridges or shelves. Other shared characteristics include an essentially featureless bony palate, without many pits and ridges, and a broad mesopterygoid fossa (the opening behind the palate). In other characteristics, Voalavo resembles some but not all species of Eliurus. For example, the length of the incisive foramina
matches the maximum seen in Eliurus species (in this case, in Eliurus majori and Eliurus penicillatus). The back margin of the incisive foramen is rounded in V. antsahabensis, but angular in V. gymnocaudus. The two species also differ in the shape of the suture (dividing line) between the maxilla
ry and palatine bone
s, which is straight in V. antsahabensis, but more curved in V. gymnocaudus. The capsular process
, a projection at the back of the mandible
(lower jaw) that houses the root of the lower incisor
, is indistinct in Voalavo, a feature it shares with E. grandidieri, E. majori, and E. petteri, but not the other species of Eliurus.
Other features of the skull distinguish the two genera. The tegmen tympani
, the roof of the tympanic cavity
, is much reduced in Voalavo relative to Eliurus. The subsquamosal fenestra
e, openings in the squamosal bone at the back of the skull, are larger in Voalavo than in Eliurus. The zygomatic plate
, a plate at the sides of the skull that roots the front part of the zygomatic arch
es (cheekbones), is narrower in Voalavo, and lacks a clear zygomatic notch (a notch formed by a projection at the front of the zygomatic plate), which is present in Eliurus. Among nesomyines, only Brachytarsomys has a more reduced zygomatic notch.
Like Eliurus, Voalavo has moderately high-crowned (hypsodont
) molars
with crowns that consist not of discrete cusps
, but of transverse laminae (plates) that generally lack longitudinal connections. However, Eliurus molars are slightly more hypsodont than those of Voalavo. The third upper and lower molars are smaller relative to the second molars in Voalavo than in Eliurus. Perhaps as a consequence, the upper third molar lacks discrete laminae in Voalavo, and the lower third molar has only two laminae (three in Eliurus). There are three roots under each upper molar and two under each lower.
forest. V. gymnocaudus is restricted to the Northern Highlands
, where it is found at 1250–1950 m (4,101–6,397.6 ft) altitude in Marojejy and Anjanaharibe-Sud. The known range of V. antsahabensis is restricted to the vicinity of Anjozorobe
at 1250–1425 m (4,101–4,675.2 ft) altitude. Although most of the 450 km (279.6 mi) between the ranges of the two species consists of montane forest—suitable habitat for Voalavo—the area is bisected by the low-lying Mandritsara Window, which may serve as a barrier between the two species. Subfossil
remains of Voalavo have been found in the former Mahajanga Province
(northwestern Madagascar).
Very little is known of the ecology of Voalavo antsahabensis, but V. gymnocaudus is thought to be largely terrestrial with some scansorial (tree-climbing) abilities. It is active during the night, bears up to three young per litter, and probably eats fruits and seeds. Various parasites have been recorded on V. gymnocaudus, including mite
s and Eimeria
.
as "Endangered". Although V. gymnocaudus also has a small range, it is mostly within protected area
s, and this species is therefore listed as "Least Concern
".
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of rodent
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
in the subfamily Nesomyinae
Nesomyinae
The Malagasy rats and mice are the sole members of the subfamily Nesomyinae. These animals are the only native rodents of Madagascar, come in many shapes and sizes, and occupy a wide variety of ecological niches. There are nesomyines that resemble gerbils, rats, mice, voles, and even rabbits...
, found only in Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
. Two species are known, both of which occur in mountain forest above 1250 m (4100 ft) altitude; Voalavo gymnocaudus lives in northern Madagascar and Voalavo antsahabensis is restricted to a small area in the central part of the island. The genus was discovered in 1994 and formally described in 1998. Within Nesomyinae, it is most closely related to the genus Eliurus
Eliurus
Eliurus is a genus of rodent in the family Nesomyidae.It contains the following species:* Tsingy Tufted-tailed Rat * Ankarana Special Reserve Tufted-tailed Rat...
, and DNA sequence
DNA sequence
The sequence or primary structure of a nucleic acid is the composition of atoms that make up the nucleic acid and the chemical bonds that bond those atoms. Because nucleic acids, such as DNA and RNA, are unbranched polymers, this specification is equivalent to specifying the sequence of...
data suggest that the current definitions of these two genera need to be changed.
Species of Voalavo are small, gray, mouse-like rodents, among the smallest nesomyines. They lack the distinctive tuft of long hairs on the tail that is characteristic of Eliurus. The tail is long and females have six mammae. In Voalavo, there are two glands on the chest (absent in Eliurus) that produce a sweet-smelling musk
Musk
Musk is a class of aromatic substances commonly used as base notes in perfumery. They include glandular secretions from animals such as the musk deer, numerous plants emitting similar fragrances, and artificial substances with similar odors. Musk was a name originally given to a substance with a...
in breeding males. In the skull, the facial skeleton is long and the braincase is smooth. The incisive foramina
Incisive foramen
The fossa incisiva is an opening in the bone of the oral hard palate where blood vessels and nerves may pass. There are four of these openings in the incisive fossa.-Formation:...
(openings in the front part of the palate) are long and the bony palate itself is smooth. The molars
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"....
are somewhat hypsodont
Hypsodont
Hypsodont dentition is characterized by high-crowned teeth and enamel which extends past the gum line. This provides extra material for wear and tear. Some examples of animals with hypsodont dentition are cows, horses and deer; all animals that feed on gritty, fibrous material. The opposite...
(high-crowned), though less so than in Eliurus, and the third molars are reduced in size and complexity.
Taxonomy
A specimen of the genus was first collected in 1994 in Anjanaharibe-Sud, northern Madagascar. The genus was named Voalavo in 1998 by Michael Carleton and Steven GoodmanSteven 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....
, with a single species, the type
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
Voalavo gymnocaudus, restricted to the Northern Highlands
Northern Highlands
The Northern Highlands are a mountainous biogeographical region of northern Madagascar. The region includes the Tsaratanana Massif and smaller nearby massifs such as Marojejy, Anjanaharibe-Sud, and Manongarivo...
of Madagascar. The generic name Voalavo is a Malagasy word for "rodent". A second species, Voalavo antsahabensis, was named by Goodman and colleagues in 2005 from the region of Anjozorobe
Anjozorobe
Anjozorobe is a large town in Analamanga Region, Madagascar, approximately 90 kilometres north-east of the capital Antananarivo.Anjozorobe is famous with its corridor and with a pilgrim city of Anosivolakely where the Virgin Maria is reported to have appeared in 1990.Anjozorobe Forest Corridor is...
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...
. The two Voalavo species are closely related and quite similar, but differ in various subtle morphological characters (mainly measurements) and by 10% in the sequence
DNA sequence
The sequence or primary structure of a nucleic acid is the composition of atoms that make up the nucleic acid and the chemical bonds that bond those atoms. Because nucleic acids, such as DNA and RNA, are unbranched polymers, this specification is equivalent to specifying the sequence of...
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...
gene 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 :...
.
Voalavo is part of the subfamily Nesomyinae
Nesomyinae
The Malagasy rats and mice are the sole members of the subfamily Nesomyinae. These animals are the only native rodents of Madagascar, come in many shapes and sizes, and occupy a wide variety of ecological niches. There are nesomyines that resemble gerbils, rats, mice, voles, and even rabbits...
, which includes nine genera that are all restricted to Madagascar. Before the discoveries of Monticolomys
Monticolomys
Monticolomys is a genus of rodents within the subfamily Nesomyinae of the family Nesomyidae, and is closely related to Macrotarsomys. The only species, Monticolomys koopmani, also known as the Malagasy Mountain Mouse or Koopman's Montane Voalavo, is found in the highlands of eastern Madagascar...
(published in 1996) and Voalavo (1998), all of the known genera within Nesomyinae were quite distinct from each other, so much so that phylogenetic relationships among them long remained obscure. Like Monticolomys (closely related to Macrotarsomys
Macrotarsomys
Macrotarsomys is a genus of rodent in the family Nesomyidae.It contains the following species:Genus Macrotarsomys - Big-footed mice*Bastard Big-Footed Mouse, Macrotarsomys bastardi Milne-Edwards and G. Grandidier, 1898...
), however, Voalavo shows clear similarities to another nesomyine genus, Eliurus
Eliurus
Eliurus is a genus of rodent in the family Nesomyidae.It contains the following species:* Tsingy Tufted-tailed Rat * Ankarana Special Reserve Tufted-tailed Rat...
. In their description of Voalavo, Carleton and Goodman argued that, although closely related, Eliurus and Voalavo form separate monophyletic groups; but a 1999 molecular phylogenetic study by Sharon Jansa and colleagues, who compared cytochrome b sequences among nesomyines and other rodents, found that Voalavo gymnocaudus was more closely related to Eliurus grandidieri than to other species of Eliurus. This finding called into question the separate generic status of Voalavo. However, tissue samples of Eliurus petteri
Eliurus petteri
Eliurus petteri is a rodent in the genus Eliurus found in lowland eastern Madagascar. First described in 1994, it is most closely related to the smaller Eliurus grandidieri. Virtually nothing is known of its natural history, except that it occurs in rainforest and is nocturnal and solitary...
, a species that is thought to be closely related to E. grandidieri, were not available, so this species could not be included in the study. Data from nuclear
Nuclear DNA
Nuclear DNA, nuclear deoxyribonucleic acid , is DNA contained within a nucleus of eukaryotic organisms. In mammals and vertebrates, nuclear DNA encodes more of the genome than the mitochondrial DNA and is composed of information inherited from two parents, one male, and one female, rather than...
genes also supports the relationship between V. gymnocaudus and E. grandidieri, but E. petteri remains genetically unstudied and the taxonomic
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
issue has not been resolved.
Molecular phylogenetic analysis of nuclear DNA supports a close relationship between Eliurus, Voalavo, and two other nesomyine genera, Gymnuromys and Brachytarsomys
Brachytarsomys
Brachytarsomys is a genus of rodent in the family Nesomyidae.It contains the following species:* White-tailed Antsangy * Brachytarsomys mahajambaensis * Hairy-tailed Antsangy...
. These genera are more distantly related to the other nesomyine genera and even more distantly to the other subfamilies of the family Nesomyidae
Nesomyidae
Nesomyidae is a family of African rodents in the large and complex superfamily Muroidea. It includes several subfamilies, all of which are native to either continental Africa or to Madagascar...
, which occur in mainland Africa.
Description
| Locality | n | Head-body | Tail | Hindfoot | Ear | Mass |
|---|---|---|---|---|---|---|
| Anjanaharibe-Sud (V. gymnocaudus) | 4 | 86–90 | 119–120 | 20–21 | – | 20.5–23.5 |
| Marojejy (V. gymnocaudus) | 5 | 80–90 | 113–126 | 17–20 | 15–15 | 17.0–25.5 |
| Anjozorobe (V. antsahabensis) | 4 | 86–91 | 106–119 | 19–21 | 15–16 | 20.7–22.6 |
| n: Number of specimens measured. All measurements are in millimeters, except body mass in grams. |
||||||
Voalavo is a small rodent resembling a mouse with gray fur. Species of the genus are among the smallest known nesomyines, close in size only to Monticolomys koopmani. In terms of external morphology, Voalavo is barely different from Eliurus; fur coloration patterns, general morphology of the feet, and number of mammae
Mammary gland
A mammary gland is an organ in mammals that produces milk to feed young offspring. Mammals get their name from the word "mammary". In ruminants such as cows, goats, and deer, the mammary glands are contained in their udders...
(six) are all the same in both genera. However, all species of Eliurus have a pronounced tuft of elongated hairs at the tip of the tail, a feature that is absent in Voalavo, although the latter does have slightly longer hairs near the tip. The tail is longer than the head and body. Relative tail length in V. gymnocaudus (136% of head and body length) is comparable to that of the longest-tailed species of Eliurus, E. grandidieri and E. petteri, but V. antsahabensis has a somewhat shorter tail. Furthermore, the pads of the feet are larger in Eliurus, and specifically, the thenar pad (located at the middle of the tarsus
Tarsus (skeleton)
In tetrapods, the tarsus is a cluster of articulating bones in each foot situated between the lower end of tibia and fibula of the lower leg and the metatarsus. In the foot the tarsus articulates with the bones of the metatarsus, which in turn articulate with the bones of the individual toes...
) is circular and fairly small in Voalavo, but longer and larger in Eliurus. On the chest, Voalavo species have a gland that produces a sweet-swelling musk in breeding males; this gland is absent in Eliurus. Unlike all other nesomyines but Brachyuromys
Brachyuromys
Brachyuromys is a genus of rodent in the family Nesomyidae.It contains the following species:* Betsileo Short-tailed Rat * Gregarious Short-tailed Rat...
, Voalavo lacks an entepicondylar foramen
Entepicondylar foramen
The entepicondylar foramen is an opening in the distal end of the humerus present in some mammals. It is often present in primitive placentals, such as the enigmatic Madagascan Plesiorycteropus...
, an opening on the humerus
Humerus
The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow....
(upper arm bone).
The skull of Voalavo also resembles that of Eliurus, with a long facial skeleton, a hourglass-shaped interorbital region
Interorbital region
The interorbital region of the skull is located between the eyes, anterior to the braincase. The form of the interorbital region may exhibit significant variation between taxonomic groups....
(between the eyes), and a smooth interorbital region and braincase, without ridges or shelves. Other shared characteristics include an essentially featureless bony palate, without many pits and ridges, and a broad mesopterygoid fossa (the opening behind the palate). In other characteristics, Voalavo resembles some but not all species of Eliurus. For example, the length of the incisive foramina
Incisive foramen
The fossa incisiva is an opening in the bone of the oral hard palate where blood vessels and nerves may pass. There are four of these openings in the incisive fossa.-Formation:...
matches the maximum seen in Eliurus species (in this case, in Eliurus majori and Eliurus penicillatus). The back margin of the incisive foramen is rounded in V. antsahabensis, but angular in V. gymnocaudus. The two species also differ in the shape of the suture (dividing line) between the maxilla
Maxilla
The maxilla is a fusion of two bones along the palatal fissure that form the upper jaw. This is similar to the mandible , which is also a fusion of two halves at the mental symphysis. Sometimes The maxilla (plural: maxillae) is a fusion of two bones along the palatal fissure that form the upper...
ry and palatine bone
Palatine bone
The palatine bone is a bone in many species of the animal kingdom, commonly termed the palatum .-Human anatomy:...
s, which is straight in V. antsahabensis, but more curved in V. gymnocaudus. The capsular process
Capsular process
In rodents, the capsular process or projection is a bony capsule that contains the root of the lower incisor. It is visible on the labial side of the mandible as a raising in the bone...
, a projection at the back of the mandible
Mandible
The mandible pronunciation or inferior maxillary bone forms the lower jaw and holds the lower teeth in place...
(lower jaw) that houses the root of the lower incisor
Incisor
Incisors are the first kind of tooth in heterodont mammals. They are located in the premaxilla above and mandible below.-Function:...
, is indistinct in Voalavo, a feature it shares with E. grandidieri, E. majori, and E. petteri, but not the other species of Eliurus.
Other features of the skull distinguish the two genera. The tegmen tympani
Tegmental wall of tympanic cavity
The Tegmental Wall or Roof is formed by a thin plate of bone, the tegmen tympani, which separates the cranial and tympanic cavities...
, the roof of the tympanic cavity
Tympanic cavity
The tympanic cavity is a small cavity surrounding the bones of the middle ear.It is formed from the tubotympanic recess, an expansion of the first pharyngeal pouch....
, is much reduced in Voalavo relative to Eliurus. The subsquamosal fenestra
Subsquamosal fenestra
In some rodents, the subsquamosal fenestra is an opening between two parts of the squamosal bone, at the back of the skull. It can be seen in lateral view. Most Oryzomyini have the fenestra, but some species, including those in the genera Nectomys, Sigmodontomys, and Melanomys among others, lack...
e, openings in the squamosal bone at the back of the skull, are larger in Voalavo than in Eliurus. The zygomatic plate
Zygomatic plate
In rodent anatomy, the zygomatic plate is a bony plate derived from the flattened front part of the zygomatic arch . At the back, it connects to the front root of the zygomatic arch, and at the top it is connected to the rest of the skull via the antorbital bridge. It is part of the maxillary...
, a plate at the sides of the skull that roots the front part of the zygomatic arch
Zygomatic arch
The zygomatic arch or cheek bone is formed by the zygomatic process of temporal bone and the temporal process of the zygomatic bone , the two being united by an oblique suture; the tendon of the Temporalis passes medial to the arch to gain insertion into the coronoid process...
es (cheekbones), is narrower in Voalavo, and lacks a clear zygomatic notch (a notch formed by a projection at the front of the zygomatic plate), which is present in Eliurus. Among nesomyines, only Brachytarsomys has a more reduced zygomatic notch.
Like Eliurus, Voalavo has moderately high-crowned (hypsodont
Hypsodont
Hypsodont dentition is characterized by high-crowned teeth and enamel which extends past the gum line. This provides extra material for wear and tear. Some examples of animals with hypsodont dentition are cows, horses and deer; all animals that feed on gritty, fibrous material. The opposite...
) molars
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"....
with crowns that consist not of discrete cusps
Cusp (dentistry)
A cusp is an occlusal or incisal eminence on a tooth.Canine teeth, otherwise known as cuspids, each possess a single cusp, while premolars, otherwise known as bicuspids, possess two each. Molars normally possess either four or five cusps...
, but of transverse laminae (plates) that generally lack longitudinal connections. However, Eliurus molars are slightly more hypsodont than those of Voalavo. The third upper and lower molars are smaller relative to the second molars in Voalavo than in Eliurus. Perhaps as a consequence, the upper third molar lacks discrete laminae in Voalavo, and the lower third molar has only two laminae (three in Eliurus). There are three roots under each upper molar and two under each lower.
Distribution and ecology
Both species of Voalavo occur in montaneMontane
In biogeography, montane is the highland area located below the subalpine zone. Montane regions generally have cooler temperatures and often have higher rainfall than the adjacent lowland regions, and are frequently home to distinct communities of plants and animals.The term "montane" means "of the...
forest. V. gymnocaudus is restricted to the Northern Highlands
Northern Highlands
The Northern Highlands are a mountainous biogeographical region of northern Madagascar. The region includes the Tsaratanana Massif and smaller nearby massifs such as Marojejy, Anjanaharibe-Sud, and Manongarivo...
, where it is found at 1250–1950 m (4,101–6,397.6 ft) altitude in Marojejy and Anjanaharibe-Sud. The known range of V. antsahabensis is restricted to the vicinity of Anjozorobe
Anjozorobe
Anjozorobe is a large town in Analamanga Region, Madagascar, approximately 90 kilometres north-east of the capital Antananarivo.Anjozorobe is famous with its corridor and with a pilgrim city of Anosivolakely where the Virgin Maria is reported to have appeared in 1990.Anjozorobe Forest Corridor is...
at 1250–1425 m (4,101–4,675.2 ft) altitude. Although most of the 450 km (279.6 mi) between the ranges of the two species consists of montane forest—suitable habitat for Voalavo—the area is bisected by the low-lying Mandritsara Window, which may serve as a barrier between the two species. Subfossil
Subfossil
Subfossil refers to remains whose fossilization process is not complete, either for lack of time or because the conditions in which they were buried were not optimal for fossilization....
remains of Voalavo have been found in the former Mahajanga Province
Mahajanga Province
Mahajanga is a former province of Madagascar with an area of 150,023 km². It had a population of 1,896,000 . Its capital was Mahajanga.Except for Fianarantsoa, Mahajanga Province bordered all of the country's other provinces:...
(northwestern Madagascar).
Very little is known of the ecology of Voalavo antsahabensis, but V. gymnocaudus is thought to be largely terrestrial with some scansorial (tree-climbing) abilities. It is active during the night, bears up to three young per litter, and probably eats fruits and seeds. Various parasites have been recorded on V. gymnocaudus, including mite
Mite
Mites, along with ticks, are small arthropods belonging to the subclass Acari and the class Arachnida. The scientific discipline devoted to the study of ticks and mites is called acarology.-Diversity and systematics:...
s and Eimeria
Eimeria
Eimeria is a genus of Apicomplexan parasites that includes various species responsible for the poultry disease coccidiosis. The genus is named for the German zoologist Theodor Eimer...
.
Conservation status
Because Voalavo antsahabensis has a small range that is threatened by the practice of slash-and-burn agriculture (known in Madagascar as tavy), it is listed on the IUCN Red ListIUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...
as "Endangered". Although V. gymnocaudus also has a small range, it is mostly within 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, and this species is therefore listed as "Least Concern
Least Concern
Least Concern is an IUCN category assigned to extant taxon or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, Near Threatened, or Conservation Dependent...
".