Tome's spiny rat (''Proechimys semispinosus''), also known as Tomes' spiny rat or the Central American spiny rat, is a species of spiny rat distributed from

Honduras Honduras, officially the Republic of Honduras, is a country in Central America. It is bordered to the west by Guatemala, to the southwest by El Salvador, to the southeast by Nicaragua, to the south by the Pacific Ocean at the Gulf of Fonseca, ...

Ecuador Ecuador, officially the Republic of Ecuador, is a country in northwestern South America, bordered by Colombia on the north, Peru on the east and south, and the Pacific Ocean on the west. It also includes the Galápagos Province which contain ...

. The

IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...

has assessed its conservation status as being of "

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

Description

Tome's spiny rat is a large rat with a head-and-body length of between and a tail length of between . The head is long and slender, with prominent eyes and narrow erect ears. At night, the eyes reflect a reddish eyeshine. The feet are long with strong nails. The

pelage A fur is a soft, thick growth of hair that covers the skin of almost all 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 ...

is sleek with spines mixed in with the dorsal fur, though these are not very obvious in the field. The upper parts are reddish-brown while the underparts are white. The tail is almost hairless and is reddish-brown above and white below. About 20% of animals encountered have no tail. This rat could be confused with the armored rat (''Hoplomys gymnurus'') which is much the same size, but the armored rat has a longer snout and smaller eyes, which are less reflective at night. Other terrestrial rats are considerably smaller and mostly have tails that are longer than their head-and-body lengths. Its

karyotype A karyotype is the general appearance of the complete set of chromosomes in the cells of a species or in an individual organism, mainly including their sizes, numbers, and shapes. Karyotyping is the process by which a karyotype is discerned by de ...

has 2n = 30 and FN = 50-54.

Distribution

The range of Tome's spiny rat extends from southeastern Honduras to southwestern Ecuador and possibly to northern Peru. It generally keeps below but in Ecuador may be found a little higher. It is a common species in evergreen and deciduous forest, favouring riparian corridors and low-lying areas. It is a tolerant and adaptable species, and the

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the stat ...

has assessed its conservation status as being of "

Ecology

Tome's spiny rat is a nocturnal, mainly ground-dwelling rat. During the day it may hide in a burrow or under a fallen tree, in a hollow log or in dense vegetation. At night it moves slowly and often sits stationary beside a tree buttress or log. It may freeze if caught in the open. It feeds on fruits and seeds, fungi, plant material and insects, carrying larger objects to a safe place before consuming them. The females can breed four times a year, producing litters of up to five

precocial Precocial species in birds and mammals are those in which the young are relatively mature and mobile from the moment of birth or hatching. They are normally nidifugous, meaning that they leave the nest shortly after birth or hatching. Altricial ...

young. The reproductive rate seems to be limited by the availability of food. On a group of small islands in Panama, each of which had its own range of tree species which fruited at different seasons, there were few births on each islet at times of fruit shortage and many at times of fruit abundance; the seasonal effects were even more marked when the spiny rat was the only frugivorous mammal on the island.

Phylogeny

Morphological characters and mitochondrial cytochrome b DNA sequences showed that ''P. semispinosus'' belongs to the so-called ''semispinosus'' group of ''Proechimys'' species, and shares closer phylogenetic affinities with the other member of this clade: '' P. oconnelli''.

Disease

Tome's spiny rat can serve as a reservoir species for the

trypanosomes Trypanosomatida is a group of kinetoplastid unicellular organisms distinguished by having only a single flagellum. The name is derived from the Greek language, Greek ''trypano'' (borer) and ''soma'' (body) because of the corkscrew-like motion of ...

that are responsible for the disease

leishmaniasis Leishmaniasis is a wide array of clinical manifestations caused by protozoal parasites of the Trypanosomatida genus ''Leishmania''. It is generally spread through the bite of Phlebotominae, phlebotomine Sandfly, sandflies, ''Phlebotomus'' an ...

, which is spread by sandflies and affects humans. The rat can be infected and harbour the parasite without showing clinical signs of the disease. It also hosts the virus ''

Thurisazvirus myis ''Thurisazvirus'' is a genus of viruses in the realm '' Ribozyviria'', containing the single species ''Thurisazvirus myis''. Tome's spiny rat (''Proechimys semispinosus Tome's spiny rat (''Proechimys semispinosus''), also known as Tomes' spin ...

''.

References

External links

* {{Taxonbar, from=Q1768762 Proechimys Mammals of Colombia Rodents of Central America Mammals described in 1860 Taxa named by Robert Fisher Tomes