Rats, mice, and relatives V

All other rats, mice, and relatives

Class Mammalia

Order Rodentia

Suborder Sciurognathi

Family Muridae

Thumbnail description
The 13 remaining subfamilies of Muridae are incredibly diverse ecologically, behaviorally, and morphologically

Size
The more than 213 species in the 13 remaining subfamilies of Muridae vary in size from small, mouse-sized animals to bamboo rats (Rhizomyinae), which can reach 8.8 lb (4 kg) in weight

Number of genera, species
47 genera; approximately 213 species

Habitat
Habitats range from deserts to dense, tropical forests; there are animals that specialize for burrowing underground, hopping across loose soils, and climbing in trees

Conservation status
Critically Endangered: 18 species; Endangered: 12 species; Vulnerable: 18 species; Lower Risk/Near Threatened: 27 species; Data Deficient: 1 species

Distribution
Found throughout Africa, Madagascar, and Asia, including Europe

Evolution and systematics

The rodent family Muridae is the largest mammalian family. Murids occur on nearly all landmasses, except for some arctic and oceanic islands, New Zealand, Antarctica, and parts of the West Indies. Morphological, ecological, behavioral, dietary, and taxonomic diversity in murids is truly astonishing. Murids range from solitary animals to highly social animals

and from very common to very rare. Murid fossils are known from the Oligocene to recent in North America and Eurasia, from the Pliocene until recent in South America, and more recently in Africa, Madagascar, and Australia.

The relationships among all subfamilies of Muridae (including those not covered here: Murinae, Sigmodontinae, Cricetinae, and Arvicolinae) are poorly understood. Careful

examination of morphological characters, especially cranial and dental characters, has not been able to elucidate patterns of relationship among the various subfamilies, although some affinities were identified. Carleton and Musser (1984), in their exhaustive morphological work, preferred to treat relationships among all murid subfamilies as unresolved.

Recent systematic work using molecular characters has helped to resolve patterns of evolutionary relationships among many murid subfamilies. Although some murid subfamilies (Lophiomyinae and Platacanthomyinae) have yet to be included in a molecular analysis, DNA sequences of representative members of all other subfamilies have been generated and analyzed within a systematic framework. Nearly all currently recognized murid subfamilies retain their rank as distinct lineages in these analyses. The fossorial lineages, Spalacinae and Rhizomyinae, appear to share a common ancestor with all of the remaining subfamilies. The remaining subfamilies form several groups of related lineages. A primarily African group (including Madagascar) includes Nesomyinae, Petromyscinae, Cricetomyinae, Dendromurinae, and Mystromyinae. Calomyscinae appears as its own lineage; the remaining subfamilies form two large lineages. A group made up mainly of Arvicolinae, Sigmodontinae, and Cricetinae includes the subfamily Myospalacinae. The final cluster is made up of the subfamilies Murinae (including

Otomyinae), Acomyinae (previously included within Murinae), and Gerbillinae.

Physical characteristics

The murid species in these subfamilies vary widely in size and other physical features. Most species are small and mouse-sized, usually with moderately long tails and a generally brownish fur color. However, many species have adopted fossorial modes of life, becoming large and robust, with reduced eyes and ears, and teeth and limbs modified for digging. Others, in particular the gerbillines, have become adapted to a nocturnal existence in primarily arid landscapes. These species are capable of jumping locomotion as a result of enlarged and modified hind limbs. They also have greatly enlarged auditory bullae, resulting in an extraordinarily keen sense of hearing. Species in several of the subfamilies strongly resemble other murid rodents such as voles (Arvicolinae) and hamsters (Cricetinae), and members of other rodent families such as pocket gophers (Geomyidae), dormice (Gliridae), jumping mice (Zapodidae), and jerboas (Dipodidae), illustrating the evolutionary plasticity of these groups.

Distribution

These 13 subfamilies are found throughout Africa, Madagascar, and Asia, including Europe.

Habitat

Murids in these subfamilies occupy a wide variety of habitats and niches. Most are terrestrial but some live underground, in trees, are semi-aquatic, or live in extreme environments. Most notable in this respect are the gerbillines, which have become adapted to extreme aridity. They avoid water loss and heat stress by being active at night, seeking refuge during the day in burrows, maintaining high relative humidity in their burrows, and producing concentrated urine. Gerbillinae is the most diverse of the 13 subfamilies,

illustrating how successful this suite of adaptations has proven.

Behavior

Members of these 13 murid subfamilies vary widely in the social structures and behaviors. Many are solitary, but some species are highly social, with complex modes of communication. Most are active primarily at night, although some are active either throughout the day, or are diurnal.

Feeding ecology and diet

Dietary diversity in these groups ranges from animals that eat mainly invertebrates to those that eat all kinds of plant matter, and some that eat vertebrates. The typical diet is made up of primarily seeds, but includes fruits, shoots, leaves, and animal matter. The fossorial subfamilies Rhizomyinae, Spalacinae, and Myospalacinae eat mainly roots and other underground plant parts, rarely venturing aboveground. The diversity in dental patterns in these groups, particularly of the cheek teeth, reflects this dietary breadth.

Reproductive biology

Reproductive patterns and behavior in these groups are quite variable. Breeding can occur seasonally or throughout the year and the number of offspring can range from one to many. In general, multiple young are born on a seasonal basis and the young develop quickly, achieving both independence and sexual maturity at an early age. However, there are exceptions. Males are typically not involved in raising young.

Very little is known about the specifics of mating behaviors in the majority of species.

Conservation status

Many species in this diverse set of subfamilies are abundant and may be human commensals and agricultural pests. However, habitat destruction or human persecution threatens many species. Animals that are restricted to small ranges or particular habitats may be especially vulnerable. For example, members of the Petromyscinae tend to be restricted to small, relict distributions and are vulnerable to habitat changes. Especially notable in this regard are the members of the Nesomyinae, which are all restricted to portions of Madagascar. This rodent radiation is truly unique and nearly all of the species in this group are critically threatened by profound, human-induced habitat destruction throughout Madagascar. Although the Gerbillinae is the most diverse of the 13 subfamilies, many species within this particular subfamily are threatened or Endangered.

Significance to humans

Species within this very diverse group include human commensals, agricultural pests, food animals, research animals, and pets. More importantly, almost all of the species in these 13 subfamilies are important members of the ecosystems in which they live. Many small rodents in this group are among the most abundant small mammals in their communities, forming an important prey base for small and large predators. Many species are also important in nutrient cycling and seed dispersal. Finally, research on the incredible array of evolutionary trajectories and adaptations found in these subfamilies will continue to yield rich and valuable insights into evolutionary processes and patterns of animal diversity. Murid rodents are some of the primary animal models used in the analysis of human diseases and genetics, and a better understanding of murid evolution and ecology directly impacts society's ability to solve problems related to human health and well-being.

Species accounts

List of Species

Mouse-like hamster

Calomyscus bailwardi

subfamily

Calomyscinae

taxonomy

Calomyscus bailwardi Thomas, 1905, Iran.

other common names

English: Asian hamster mouse.

physical characteristics

Head and body length 2.4–3.8 in (61–98 mm); tail 2.8–4 in (72–102 mm); weigh 0.5–1 oz (15–30 g). The fur is fine and soft, a sandy brown above and creamy white on the belly and feet. Tail is furry, and tufted at the end; dark above and white below. The ears are large and rounded, and whiskers are long. They have four-rooted molar teeth.

distribution

Central Asia, including Iran, Caucasus, Turkmenistan, Afghanistan, and Pakistan.

habitat

Found in a variety of habitats, from barren hillsides to wet forests, and from 1,310 to 11,480 ft (400–3,500 m) elevation. They build nests in rock crevices and other protected areas; nests are woven of grasses and other soft materials, including wool.

behavior

Not highly social animals, but they can be found sheltering together in the wild and they huddle together in captivity. They are active at night during summer, but may extend activity into the dawn and dusk hours during spring and fall.

feeding ecology and diet

Eat primarily seeds, but also eat flowers, leaves, and animal foods when available.

reproductive biology

Breeding may occur twice yearly, with a peak of reproduction in spring and then a late season breeding period; this may vary regionally and depend on food availability. Young are born hairless and with their eyes closed; they develop quickly and reach adult size at 6–8 months old.

conservation status

There is very little known on the status of this calomyscine mouse, or other species in this genus. Two species are listed as Vulnerable in Russia. They may be locally abundant. Calomyscus hotsoni, of Pakistan, is considered endangered.

significance to humans

Where Calomyscus species are abundant and live near human habitations, they may act as agricultural pests or harbor disease agents. However, they are more likely to have little to no effect on humans, except in their role as members of healthy ecosystems.

White-tailed mouse

Mystromys albicaudatus

subfamily

Mystromyinae

taxonomy

Mystromys albicaudatus (Smith, 1834), South Africa, eastern Cape Province.

other common names

None known.

physical characteristics

Critical differences, including their lack of check pouches, in the single species in this subfamily led to their elevation to the subfamily level, though their affinities remain obscure. Head and body length 3.3–4.1 in (84–105 mm); weigh 2.6–3.9 oz (75–111 g); tail 1.9–3.8 in (50–97 mm). The fur is soft and long, buffy gray above with black-tipped hairs; this darker dorsal coloration gradually lightens along the sides to the entirely white belly. The thick tail is covered with stiff bristles and the ears are large and rounded. The incisors are pale yellow and ungrooved, and the cheek tooth laminar pattern is unique.

distribution

Found in the uplands and Cape region of South Africa and Swaziland.

habitat

Found in grassy and sandy areas, they live in holes in the ground and the burrows of other mammals.

behavior

Active mainly at night and may be especially active during wet weather. They do well in captivity, becoming tame and playful. Little is known about their social behavior.

feeding ecology and diet

Seeds seem to be their primary diet, though grasses and insects are also sometimes taken.

reproductive biology

Have an unusual method of raising young: soon after birth, the young attach themselves to their mother's mammae and remain attached for about three weeks. The female drags them about during this time. They continue to suckle intermittently for another 2–3 weeks. The survival rate of young is high for rodents, as the mother can provide direct protection for her young. Sexual maturity is reached at about five months of age and litters can be produced as often as every 36 days. Mean litter size is 2.9 young. In captivity, they may live as long as six years; lifespan in the wild is unknown.

conservation status

Little is known. Populations may be threatened by modifications to their habitat as a result of agriculture and grazing, and they are considered Vulnerable by the IUCN.

significance to humans

Although they may act as disease vectors and agricultural pests, it is most likely that they have a minimal effect on humans. They are important parts of the ecosystems in which they live, acting as seed dispersers and an important prey base for small predators.

Gambian rat

Cricetomys gambianus

subfamily

Cricetomyinae

taxonomy

Cricetomys gambianus Waterhouse, 1840, River Gambia, Gambia.

other common names

English: African pouched rat/mouse.

physical characteristics

Fairly large: head and body length 9.4–17.7 in (240–450 mm); tail 14.3–18.1 in (365–460 mm); weight, males 6.1 lb (2.8 kg) and females 3 lb (1.4 kg). The fur is short and ranges from coarse to soft. They are generally dark or grayish brown with red tinges on their upperparts and creamy on the underparts. Their large ears and long, scaly tail are hairless and the tail is completely white for the last half of its length. There is a dark ring around each eye, making them appear masked. Some individuals are mottled with darker colors or may have an indistinct white line running across their shoulders. The head and face are long and narrow and the eyes are relatively small. They have cheek pouches into which they stuff food, bedding material, and found objects such as pebbles and metal trash, which they take back to their burrows. The incisors are ungrooved.

distribution

Found in appropriate habitat from Senegal and Sierra Leone in the west to Sudan and Uganda in the east and as far south as Zambia, Angola, and northern South Africa.

habitat

Prefer forests, thickets, and forest edge habitats, and are sometimes found in grasslands.

behavior

Mainly nocturnal, though they are sometimes observed during daylight hours. Their relatively small eyes and their behavior during the daytime suggest that they rely mainly on their senses of smell and hearing. They can dig their own, simple burrows, consisting of long passageways with side chambers for bedding and storage; however, they also use the burrows of other animals, termite mounds, or natural crevices such as rock crevices or hollow trees. Burrows usually have several openings that are camouflaged by dense vegetation. Burrow entrances are often plugged with vegetation from the inside. They can climb well and swim, and appear to be mainly solitary.

feeding ecology and diet

Omnivorous, eating all kinds of plant and animal matter, including insects, fruits, seeds, nuts, roots, leaves, snails, and crabs. They prefer palm fruits and kernels.

reproductive biology

Breeding can occur throughout the year, depending on the nutritional status of females. In a captive study, a female had five litters in one year and it was estimated that as many as 10 litters per year could be produced. Gestation lasts from 27–36 days; an average of four young (with a range of 1–5) is born per litter. Young develop quickly and become sexually mature as early as 20 weeks old. One individual in captivity lived almost eight years.

conservation status

Although common in some areas, they are less common in others. In South Africa, they are classified as Rare.

significance to humans

Often sold in the pet trade, Gambian rats were banned from import into the United States in 2003 in an effort to prevent the spread of monkeypox virus infection. They are also hunted as food by native peoples.

Pygmy rock mouse

Petromyscus collinus

subfamily

Petromyscinae

taxonomy

Petromyscus collinus (Thomas and Hinton, 1925), Damaraland, Namibia.

other common names

None known.

physical characteristics

Head and body length 2.7–3.5 in (70–90 mm); tail 3.1–3.9 in (80–100 mm). Small, mouse-sized rodents with broad, flattened heads and large ears. Their long tails are scaly and sparsely furred, and the pelage is soft and brown above and grayish below. Dental characteristics suggest they are related to members of the subfamilies Dendromurinae and Mystromyinae, but they are distinctive in other characters.

distribution

Found in the arid regions of southwestern Africa. Petromyscus collinus is found from southern Angola to western South Africa in the Namib Desert.

habitat

Found in areas of boulders and rock outcroppings in arid mountainous regions.

behavior

Nocturnal, they shelter during the day in rock crevices and among loose boulders and forage in the same areas at night by creeping among the rocks. Very little is known about these animals.

feeding ecology and diet

Observations suggest they are omnivorous, taking advantage of many food types as they are available.

reproductive biology

Breed once yearly, with births peaking in January, preceding the main rainy season. Litter size is estimated at 2–3 young.

conservation status

Little is known about the population status. The areas they occupy are remote and little used by humans, though their limited distribution makes them potentially Vulnerable.

significance to humans

The remote areas they occupy do not support dense human settlements; it is unlikely that there are any direct effects of Petromyscus species on humans.

Gray climbing mouse

Dendromus melanotis

subfamily

Dendromurinae

taxonomy

Dendromus melanotis Smith, 1834, near Port Natal, South Africa.

other common names

English: African climbing mouse, gerbil mouse, fat mouse, forest mouse.

physical characteristics

Head and body length 1.9–3.9 in (50–100 mm); tail 2.5–5.1 in (65–132 mm); weight 0.2–0.7 oz (5–21 g). They have three digits on their forefeet, a characteristic unique to the genus; the rear feet have the normal number of digits. Their long,

prehensile tails are slightly bicolored, darker on the upper surface. The dorsal fur is soft and gray, with a darker stripe running down their midline, their underparts are lighter. The eyes are very large and often have darker fur surrounding them, making them look as if they have spectacles. Upper incisors are grooved.

distribution

Widely distributed in suitable habitats in Central Africa, from Guinea in the west to Ethiopia in the east and as far south as South Africa. Some other Dendromus species have very restricted ranges.

habitat

In general, found in a wide variety of habitats, from arid grasslands to dense, moist forests. D. melanotis is found mainly in dry, open grasslands, often in sparse vegetation on sandy soils, but also in swampy areas, coastal lowlands, low velds, moist upland, and montane areas. They make simple burrows underground, consisting of entrance and exit tunnels and a grasslined nest chamber. Other Dendromus species build globular nests aboveground. Several Dendromus species, which occupy similar habitats, may build their burrows underground to escape the seasonal fires that are typical of the grasslands in which they live.

behavior

There is variation in the degree of sociality among Dendromus species, but they are solitary and quite territorial. They are active at night and use their tails for climbing.

feeding ecology and diet

Omnivorous, eating seeds, fruits, insects, and small vertebrates.

reproductive biology

The time of breeding may vary regionally, based on wet season timing and food availability, but they breed only once yearly. Gestation lasts 23–27 days, after which 2–8 young are born in the mother's nest. The young are cared for by their mother until they are 30–35 days old, after which they leave the nest.

conservation status

Population information on most Dendromus species is unavailable. They may be locally abundant in suitable habitats, but some are Vulnerable to human disturbances of their habitat. D. vernayi of Angola is considered Critically Endangered by IUCN.

significance to humans

May act as disease vectors and agricultural pests of seed crops, but their impact on humans is likely to be minimal.

Malagasy giant rat

Hypogeomys antimena

subfamily

Nesomyinae

taxonomy

Hypogeomys antimena Grandidier, 1869, Madagascar.

other common names

English: Malagasy rat/mouse.

physical characteristics

Large rodents: head and body length 11.8–19.6 in (300–500 mm); tail 8.2–19.6 in (210–500 mm). Their ears are quite large, reaching 2.3 in (60 mm) in length. They tend to sit back on their well-muscled haunches and long hind feet and are excellent jumpers and runners. The fur is coarse and short; their dorsal fur is gray, brown, or reddish, and the fur on their belly, feet, and hands is white. The dark tail is covered with stiff hairs.

distribution

West coast of Madagascar.

habitat

Found only in the sandy forests of western coastal Madagascar. They construct long, deep burrows in the sandy soil.

behavior

Nocturnal, emerging from their burrows at nightfall to search for food.

feeding ecology and diet

Eat mainly fallen fruit.

reproductive biology

Very little is known. They give birth to single young.

conservation status

Threatened by habitat destruction as the virgin forests of Madagascar are cut and burned for agriculture by a burgeoning human population. Populations have decreased in number and range in recent years; they are listed as Endangered by IUCN.

significance to humans

Along with other nesomyine rodents, they are remarkable examples of an adaptive radiation into unoccupied niches on Madagascar. They are significant as a kind of natural experiment in murid evolution. They may also be important in dispersing seeds of native vegetation, though little research has been done on their ecosystem roles and ecology.

Sundevall's jird

Meriones crassus

subfamily

Gerbillinae

taxonomy

Meriones crassus Sundevall, 1842, Sinai, Egypt.

other common names

English: Gentle jird, gerbil, sand rat.

physical characteristics

Slightly larger than mouse-sized: head and body length 5.9 in (150 mm); tail 5.9 (150 mm); weight 1.6–2.1 oz (45–60 g). Tail is sparsely furred, with a brush-like tip. The fur is soft and fine, their undersides are entirely white, and their dorsal surfaces are gray to buffy.

distribution

Occur throughout the Arabian Peninsula, Iran, and Iraq, and into Turkey and Syria. Also found throughout much of Africa north of 20°N latitude, from Morocco to Sudan.

habitat

Prefer the most arid, hot, and open habitats throughout their range. Typically found in areas with sandy soils, but can also be found in rocky areas. They are well adapted to their arid

habitats; they have efficient kidneys that produce highly concentrated urine. They also defecate fecal material that is very dry. Maintain a high relative humidity in burrows, close to 100% in their deepest parts.

behavior

Escape both the heat and aridity of the daylight hours and the diurnal predators by being mainly nocturnal, though their remains have been found in owl pellets. They are social animals, living in small colonies that occupy complex burrow systems.

feeding ecology and diet

Diet consists mainly of seeds, though fruits, and foliage; insects are also taken. Recorded eating Acacia, thistle, locust, and other plant seeds, melons, dates, and orthoperan insects (crickets and locusts). They shift to include more foliage in their diet during winter, possibly as a way of increasing moisture intake. Food is brought back to the burrow before being consumed, and parts of the burrow are used for food storage.

reproductive biology

Capable of breeding at an early age, as early as two months old, and breeding can occur throughout the year. Courtship and mating behavior is relatively complex. Males display to females by foot-stomping and tail-beating. Mating occurs at night for several hours at a time, during which copulation occurs repeatedly. Females groom males during mating sessions. From one to eight young (average 3.5) are born in each litter. Young are born naked and helpless and are cared for by their mother in the burrow. They develop rapidly, becoming weaned after one month. Gestation is from 21 to 31 days in length, with a 4.5 day long estrus. The length of estrus and gestation is influenced by the mother's nutritional and reproductive state.

conservation status

Fairly common throughout their range. They tend to occupy habitats that are undesirable to humans, and are therefore less disturbed. However, several other Meriones species are considered Endangered.

significance to humans

Several species are common in the pet trade and in medical and biological research. In the wild, they may be considered agricultural pests because they damage seed and fruit crops. Their burrowing activities may cause damage to structures such as irrigation canals. They are also critical natural components of the ecosystems in which they live.

Angoni vlei rat

Otomys angoniensis

subfamily

Otomyinae

taxonomy

Otomys angoniensis Wroughton, 1906, Malawi.

other common names

English: Vlei rats, whistling rats, karoo rats, groove-toothed rats.

physical characteristics

Medium-sized, stocky rodents: head and body length 4.1–8.1 in (105–207 mm); tail 1.7–5.1 in (43–131 mm); weight 0.8–4.8 oz (25–138 g). Males and females are approximately the same size. The majority of this large amount of variation in size is distributed across regional populations. The blunt face and short ears give them an almost vole-like appearance. The fur is soft and long and is almost uniformly dark gray, brown, or reddish, with the underparts being slightly lighter. Tail is sparsely furred, dark above, and light below. Incisors are ungrooved and yellow.

distribution

Are found from southern Kenya to northeastern Cape Province, South Africa.

habitat

Found in the savannas and grasslands of central and southern Africa below 8,200 ft (2,500 m) in elevation. They are most common in moist, dense grasslands. They build nests in dense grass or in burrows, and runway systems through and under grasses and vegetation that form a dense canopy.

behavior

Solitary animals, although congregations may occur near water and quality food sources. Throughout much of their range, they are active during the day, although they are primarily nocturnal in other areas. They swim across shallow water readily.

feeding ecology and diet

Herbivorous, eating mainly grasses, and reed shoots, roots, and rhizomes. Their hindguts are complex and elongated to accommodate their herbivorous diet. They also eat bark and seeds on occasion. Grass stems are cut off at their base and the tender parts eaten.

reproductive biology

Reproduction is not well understood. They may begin breeding at four months old and breed several times in a year, with births peaking during wet seasons. Breeding is synchronized by photoperiod changes. Information on gestation period, number of young, and the development of young is unavailable. However, museum records indicate the litter size may be from one to five young. Young are born well developed, with a full coat of fur and their incisors, which they use to cling to their mother's nipples for a period of time.

conservation status

Common throughout their range, they are not considered threatened. Their close relative Otomys occidentalis of Cameroon and Nigeria is considered Endangered.

significance to humans

Captured and eaten by humans in some areas. They are important parts of grassland ecosystems, involved in recycling nutrients and acting as an important and abundant prey base for small predators.

Crested rat

Lophiomys imhausi

subfamily

Lophiomyinae

taxonomy

Lophiomys imhausi Milne–Edwards, 1867, Somalia.

other common names

English: Maned rat.

physical characteristics

Distinguished by a number of distinctive features. Head and body length 10–14.1 in (255–360 mm); tail 5.5–8.4 in (140–215 mm); weight 20.8–32.4 oz (590–920 g). Females are typically larger than males. The fur is long, dense and silky, except for an erectile crest of coarse fur along the back and onto the tail; this crest, or mane, is raised when the animal is startled. The fur on either side of the mane is shorter, and lighter in color, having the effect of emphasizing the mane. The fur is generally brown or black with a pattern of white stripes and spots extending from the head. Individual hairs are banded with dark and light color, giving them a frosted appearance. The underparts are dark in color and the feet are black; the tail is bushy and tipped in white. They have a blunt face and short, rounded ears; they resemble small porcupines. They have four digits on their hands and feet and a partially opposable thumb, making them well adapted to arboreal life. Their skulls are strangely modified; the temporal fossae are entirely covered in bone and the surface of the skull appears granulated.

distribution

Found in southern Sudan, Ethiopia, Somalia, Kenya, and Sudan.

habitat

There is some disagreement on what kinds of habitats they are found in They are generally believed to be restricted to montane forests, but are found from sea level to 10,825 ft (3,300m) in Ethiopia in a variety of habitats.

behavior

Nocturnal and solitary, they emerge from their burrows at dusk to begin foraging. They are arboreal and are adept at climbing, though they do so slowly. They emit hissing, snorting, and growling sounds.

feeding ecology and diet

Herbivorous, they use their hands to grasp leaves and shoots and eat them while sitting on their hindquarters.

reproductive biology

Very little is known about their reproduction. They may have one to three young at a time, which develop quickly and are capable of feeding on their own at 40 days old. May live for a long time, reaching almost eight years old in captivity.

conservation status

Information on populations is incomplete; they are not currently listed as threatened.

significance to humans

May be eaten by natives on occasion.

Malabar spiny dormouse

Platacanthomys lasiurus

subfamily

Platacanthomyinae

taxonomy

Platacanthomys lasiurus Blyth, 1859, India.

other common names

English: Malabar spiny mouse, and blind tree mice.

physical characteristics

Head and body length 5.1–8.3 in (130–212 mm); tail 2.9–3.9 in (75–100 mm) long. They have a delicate, pointed muzzle, small eyes, and naked ears. Their dental formula is the same as other murids and they lack premolars. The underfur is dense and soft and is intermixed with a thick layer of flattened spines on the back and fewer, smaller spines on the underparts. The tail is long, sparsely furred, scaly, and is tipped with long hairs that form a distinct brush. Fur color is generally reddish brown on the back and head and grayish white on the belly and feet. The tail is darker than body color, but terminates in a light-colored tip.

distribution

Occur in southern India in habitats below 9,840 ft (3,000 m).

habitat

Typically found in forested habitats and rocky hillsides between 1,970–2,950 ft (600–900 m) in elevation. They construct nests of leaves and moss in trees and rock crevices.

behavior

Arboreal, moving by climbing and leaping in trees. They are active at night.

feeding ecology and diet

Eat fruit, grains, seeds, and roots. They are called "pepper rats" because they eat large quantities of pepper fruits.

reproductive biology

The specifics of reproduction are unknown.

conservation status

Quite abundant and are not considered threatened.

significance to humans

Locally abundant, becoming agricultural pests in some areas, particularly on pepper crops.

Siberian zokor

Myospalax myospalax

subfamily

Myospalacinae

taxonomy

Myospalax myospalax (Laxmann, 1773), Russia.

other common names

English: Zokors.

physical characteristics

Head and body length 5.9–10.6 in (150–270 mm); tail 1.1–3.7 in (29–96 mm). Stout, torpedo-shaped animals with powerful limbs and claws suitable for digging. Their eyes are very small and are often covered by the fur and there are no external ears, both adaptations for their fossorial lifestyle. The fur is soft, long, and lacks guard hairs. Color varies among different shades of brown and gray, with the underparts being slightly lighter than the upper parts. Individual hairs are often darker at the tips.

distribution

Found in Russia and Kazakhstan.

habitat

Found in forested and agricultural areas with soils suitable for their digging activities. They live almost entirely underground, digging long tunnels very rapidly. Their presence is easily determined by a characteristic mound pattern. Burrows are created in a similar manner and consist of nest chambers, food storage areas, a defecation chamber, and a series of tunnels. Burrows are generally at depths of 6.5 ft (2 m).

behavior

Active throughout the year and throughout the day. They sometimes emerge from their underground tunnels to forage on the surface at night. Despite their much-reduced eyes, they seem sensitive to light. They squeal when disturbed.

feeding ecology and diet

Eat mainly roots and grains. They burrow underground to gain access to roots.

reproductive biology

Not much is known about reproduction. Females with 2–6 young have been captured in spring, but reproduction could occur at other times.

conservation status

Several zokor species, including Siberian zokors, are not considered threatened, but at least four are considered Vulnerable by IUCN.

significance to humans

Can be agricultural pests and are actively hunted to reduce population sizes.

Palestine mole rat

Nannospalax ehrenbergi

subfamily

Spalacinae

taxonomy

Nannospalax ehrenbergi (Nehring, 1898), Jaffa, Israel.

other common names

English: Blind mole rat.

physical characteristics

Head and body length 5.9–10.6 in (150–270 mm); there is no external tail. Characterized by the lack of external openings for the eyes and ears. Small eyes are present below the skin and the ears are reduced to a small ridge. There are sets of whiskers along the face to aid in tactile sensation and it is thought that their sense of hearing is acute. They are robustly built, with a large head, powerful limbs, and a streamlined body. Their incisors are very large and project beyond the lips when the mouth is closed. The claws are small.

distribution

Found along the coasts of the Mediterranean Sea from Libya, through Egypt, Palestine, and Syria.

habitat

Prefer to occupy areas with sandy or loamy soils and are found in a variety of habitats. They do not occur in desert areas. They spend most of their lives in their underground burrow systems, which are complex and made up of multiple foraging tunnels, nest chambers, storage areas, and latrines. Burrow depth is influenced by weather, with burrows occurring deeper in the hot, summer months. Burrow systems may also include mounds, which are found aboveground. In the center of the mounds are sleeping chambers.

behavior

Solitary and active throughout the day. Burrow systems are generally occupied by single animals.

feeding ecology and diet

Eat the underground parts of plants, including roots, tubers, stems, and seeds that can be obtained from below ground. Food is stored in underground chambers.

reproductive biology

Apparently use an unusual form of locating mates, whereby males and females produce vibrations by drumming the top of their head against burrow ceilings. During the mating season, females construct elaborate, aboveground breeding mounds made up of tunnels and multiple chambers. The central chamber is the nest chamber. Males construct mounds surrounding the breeding mound of a female. Mating occurs once yearly from November–March and young are born from January–April. Litter size is one to five young. These young are born naked and helpless, but develop quickly, leaving the nest at 4–6 weeks old. Maximum lifespan in the wild is 4.5 years.

conservation status

Not currently considered threatened, though, in general, they may be vulnerable to habitat modifications and persecution by humans.

significance to humans

Considered agricultural pests in some areas, but in other regions are not considered destructive. In Libya, it is believed that blindness results from touching a mole rat, so they are left unharmed. They have been instrumental in locating significant archeological sites by bringing buried items to the surface.

Large bamboo rat

Rhizomys sumatrensis

subfamily

Rhizomyinae

taxonomy

Rhizomys sumatrensis (Raffles, 1821), Malacca, Malaysia.

other common names

English: African mole rat, bamboo rat, root rat.

physical characteristics

The largest species of bamboo rat: head and body length to 18.9 in (480 mm); tail to 7.8 in (200 mm); weight to 8.8 lb (4 kg). They have robust, streamlined bodies, with powerful limbs, strong claws, procumbent, orange incisors, and small eyes and ears. The fur is short and coarse, and is generally light gray. Individual hairs are tipped in white, giving them a frosted appearance. Their tails are scaled and without fur. Similar in appearance to American pocket gophers, but lack cheek pouches.

distribution

Found in Myanmar, Thailand, throughout Indochina, the Malay Peninsula, and Sumatra.

habitat

Live in bamboo forests at elevations between 3,937–13,123 ft (1,200–4,000 m). They spend much of their lives in their underground burrows among the bamboo roots. Individuals use both their teeth and powerful claws to dig several burrows, each of which has is made up of foraging tunnels and nest chambers.

behavior

Not much is known about their behavior. They move slowly and can be fierce when cornered. They emit grunting and tooth-grinding noises when upset. They are probably solitary and active throughout the day.

feeding ecology and diet

Eat primarily bamboo roots, but will also forage aboveground at night, when they take stems, leaves, fruit, and seeds. They have been observed climbing bamboo stalks to cut sections that are then taken into the burrow.

reproductive biology

Breeding occurs twice yearly, once from February–April and again from August–October. Litter size is one to five young. They are born naked and helpless in their mother's nest chamber, but develop quickly, being able to eat plant foods at one month old. They live for about four years.

conservation status

Not currently threatened, though they may be vulnerable to habitat destruction and persecution by humans.

significance to humans

Sometimes are agricultural pests, especially of sugar cane and tapioca roots. They are captured as food by humans.

Resources

Books

Carleton, M. D., and G. G. Musser. "Muroid Rodents." In Orders and Families of Recent Mammals of the World, edited by S. Anderson and J.K. Jones Jr. New York: John Wiley and Sons, 1984.

Kingdon, Jonathan. The Kingdon Field Guide to AfricanMammals. London: Academic Press, 1997.

Nowak, Ronald, M. Walker's Mammals of the World. Vol. 2, 6th ed. Baltimore: Johns Hopkins University Press, 1997.

Wilson, Don E., and DeeAnn Reeder. Mammal Species of theWorld: A Taxonomic and Geographic Reference. 2nd ed. Washington, DC: Smithsonian Institution Press, 1993.

Periodicals

Bronner, G. N., and J. A. J. Meester. "Otomys angoniensis." Mammalian Species 306 (1988): 1–6.

Bronner, G., S. Gordon, and J. Meester. "Otomys irroratus." Mammalian Species 308 (1988): 1–6.

Dempster, Edith, R., Michael R. Perrin, Colleen T. Downs, and Michael Griffin. "Gerbillurus setzeri." Mammalian Species 598 (1998): 1–4.

Dempster, Edith, R., Michael R. Perrin, and Colleen T. Downs. "Gerbillurus vallinus." Mammalian Species 605(1999): 1–4.

Gulotta, Elizabeth Fryatt. "Meriones unguiculatus." MammalianSpecies 3 (1971): 1–5.

Koffler, Barry R. "Meriones crassus." Mammalian Species 9 (1972): 1–4.

Michaux, Johan, Aurelio Reyes, and François Catzelflis. "Evolutionary History of the Most Speciose Mammals: Molecular Phylogeny of Muroid Rodents." Molecular Biology and Evolution 18 (2001): 2017–2031.

Perrin, Michael R., Edith R. Dempster, and Colleen T. Downs. "Gerbillurus paeba." Mammalian Species 606 (1999): 1–6.

Perrin, Michael R., Edith R. Dempster, Colleen T. Downs, and David C. Boyer. "Gerbillurus tytonis." Mammalian Species 609 (1999): 1–4.

Yalden, D.W. "Tachyoryctes macrocephalus." Mammalian Species 237 (1985): 1–3.

Other

Myers, Philip. Animal Diversity Web. "Subfamilies of Muridae." [May 3, 2003]. <http://animaldiversity.ummz.umich.edu/anat/murid_subfams.html>.

Tanya Anne Dewey