The Malayan field rat, Malaysian field rat or Malaysian wood rat, (''Rattus tiomanicus'') is a species of

rodent Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are n ...

in the family Muridae. It is nocturnal and mainly arboreal and is found in

Malaysia Malaysia ( ; ) is a country in Southeast Asia. The federation, federal constitutional monarchy consists of States and federal territories of Malaysia, thirteen states and three federal territories, separated by the South China Sea into two r ...

Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is b ...

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...

and the

Philippines The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

. It is a common species and the

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of nat ...

has assessed it as being of "

least concern A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. T ...

Description

The Malayan field rat has a head-and-body length of and a tail . It has a weight of between . The ears are large and nearly naked. The fur is smooth and flattened, interspersed with short spines. The dorsal

pelage Fur is a thick growth of hair that covers the skin of mammals. It consists of a combination of oily guard hair on top and thick underfur beneath. The guard hair keeps moisture from reaching the skin; the underfur acts as an insulating blanket ...

is a grizzled olive-brown with scattered medium-length black guard hairs, and the underparts are whitish. The tail, which is a similar length to the body, is a uniform dark brown. The feet are broad, and the soles have fine ridges for climbing. It differs from Annandale's rat (''Rattus annandalei'') in having sleek fur with spines and fewer

mammae A mammary gland is an exocrine gland in humans and other mammals that produces milk to feed young offspring. Mammals get their name from the Latin word ''mamma'', "breast". The mammary glands are arranged in organs such as the breasts in primat ...

, and from the ricefield rat (''Rattus argentiventer'') in having plain white underparts and lacking an orange spot in front of the ear.

Distribution and habitat

The Malayan field rat is known from Malaysia, Thailand, Sumatra, Borneo, the Philippines and many smaller islands. Its typical habitat is primary and secondary forest, including coastal forest but it is seldom found in

dipterocarp Dipterocarpaceae is a family of 16 genera and about 695 known species of mainly tropical lowland rainforest trees. The family name, from the type genus ''Dipterocarpus'', is derived from Greek (''di'' = two, ''pteron'' = wing and ''karpos'' = f ...

forests. It is also found in plantations, shrubby areas, grassland and gardens, but seldom invades buildings.

Behaviour

The Malayan field rat is nocturnal. It climbs well and spends much of its time in trees as well as foraging on the ground. It hides in log piles, heaps of palm fronds, under fallen logs and in the crowns of palm trees. It feeds on both vegetable and animal matter, with oil palm fruits forming part of its diet.

Status

The Malayan field rat is an abundant and adaptable species with a very wide range, a large total population and an ability to live in a number of different environments. No particular threats have been identified, and in some areas it is regarded as a pest. The

has assessed its conservation status as being of "

References

* {{Taxonbar, from=Q139675 Rattus Rats of Asia Rodents of Indonesia Rodents of Malaysia Rodents of the Philippines Rodents of Thailand Mammals of Brunei Mammals of Borneo Mammals described in 1900 Taxonomy articles created by Polbot