''Hylomyscus endorobae'' is a species of

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

of the genus ''

Hylomyscus ''Hylomyscus'' is a genus of rodent in the family Muridae endemic to Africa. It contains 21 species divided into six species groups: *''H. aeta'' group **Beaded wood mouse, ''Hylomyscus aeta'' **Mount Oku wood mouse, ''Hylomyscus grandis'' *'' ...

'' that is found only in select portions of the wet

East African montane forests The East African montane forests is a montane tropical moist forest ecoregion of eastern Africa. The ecoregion comprises several separate areas above 2000 meters in the mountains of South Sudan, Uganda, Kenya, and Tanzania. Geography The East Af ...

of the

Kenyan Rift The Great Rift Valley is part of an intra-continental ridge system that runs through Kenya from north to south. It is part of the Gregory Rift, the eastern branch of the East African Rift, which starts in Tanzania to the south and continues no ...

mountains of southwestern

Kenya Kenya, officially the Republic of Kenya, is a country located in East Africa. With an estimated population of more than 52.4 million as of mid-2024, Kenya is the 27th-most-populous country in the world and the 7th most populous in Africa. ...

and

Tanzania Tanzania, officially the United Republic of Tanzania, is a country in East Africa within the African Great Lakes region. It is bordered by Uganda to the northwest; Kenya to the northeast; the Indian Ocean to the east; Mozambique and Malawi to t ...

, and only at elevations above . It was described in 1910 as ''Epimys endorobae'' and initially considered a distinct species. It was later reclassified as a

synonym A synonym is a word, morpheme, or phrase that means precisely or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are a ...

of '' Hylomyscus denniae'', thought to be a widespread species but with a disjunct distribution among the

tropical wet forest Tropical and subtropical moist broadleaf forests (TSMF), also known as tropical moist forest, is a subtropical and tropical forest habitat type defined by the World Wide Fund for Nature (WWF). Description TSMF is generally found in large ...

s of a broader

afromontane The Afromontane regions are subregions of the Afrotropical realm, one of the Earth's eight biogeographic realms, covering the plant and animal species found in the mountains of Africa and the southern Arabian Peninsula. The Afromontane regions o ...

biotic region. It had also been interpreted as a small form of the genus ''

Praomys ''Praomys'' is a genus of rodent in the family Muridae endemic to Sub-Saharan Africa Sub-Saharan Africa is the area and regions of the continent of Africa that lie south of the Sahara. These include Central Africa, East Africa, Southern A ...

''. In 2006, ''Hylomyscus'' and ''Praomys'' were confirmed to be distinct genus-group

taxa In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and ...

, and ''H. endorobae'' was again recognized as a distinct species. Twelve species of ''Hylomyscus'' are currently recognized, provisionally arranged in six groups. ''H. endorobae'' together with ''H. denniae'' and '' H. vulcanorum'' comprise the ''H. denniae'' group. These three species are quite similar, and they occupy similar habitats that are in relative close proximity to one another. However, because they exclusively inhabit wet montane forests above 2,000 m, they are geographically isolated from one another, in much the same way that some species become

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to particular islands. ''H. endorobae'' appears to be endemic to the Kenyan Rift mountains east of

Lake Victoria Lake Victoria is one of the African Great Lakes. With a surface area of approximately , Lake Victoria is Africa's largest lake by area, the world's largest tropics, tropical lake, and the world's second-largest fresh water lake by surface are ...

from

Mount Elgon Mount Elgon is an extinct shield volcano on the border of Uganda and Kenya, north of Kisumu and west of Kitale. The mountain's highest point, named "Wagagai", is located entirely within Uganda.

Mount Kenya Mount Kenya (Meru people, Meru: ''Kĩrĩmaara,'' Kikuyu people, Kikuyu: ''Kĩrĩnyaga'', Kamba language, Kamba: ''Ki nyaa'', Embu language, Embu: ''Kĩ nyaga'') is an extinct volcano in Kenya and the Highest mountain peaks of Africa, second-highe ...

. ''H. denniae'', on the other hand, is endemic to the

Ruwenzori Mountains The Rwenzori (also known as the Ruwenzori, Rwenzururu or Rwenjura) are a mountain range, range of mountains in eastern equatorial Africa, located on the border between Uganda and the Democratic Republic of the Congo. The highest peak of the Ruw ...

, along the border between

Uganda Uganda, officially the Republic of Uganda, is a landlocked country in East Africa. It is bordered to the east by Kenya, to the north by South Sudan, to the west by the Democratic Republic of the Congo, to the south-west by Rwanda, and to the ...

and the

Democratic Republic of the Congo The Democratic Republic of the Congo (DRC), also known as the DR Congo, Congo-Kinshasa, or simply the Congo (the last ambiguously also referring to the neighbouring Republic of the Congo), is a country in Central Africa. By land area, it is t ...

, while ''H. vulcanorum'' is found just south of the Equator, in

Burundi Burundi, officially the Republic of Burundi, is a landlocked country in East Africa. It is located in the Great Rift Valley at the junction between the African Great Lakes region and Southeast Africa, with a population of over 14 million peop ...

Rwanda Rwanda, officially the Republic of Rwanda, is a landlocked country in the Great Rift Valley of East Africa, where the African Great Lakes region and Southeast Africa converge. Located a few degrees south of the Equator, Rwanda is bordered by ...

, and the D.R. Congo. Eight characteristics distinguish the various members of the genus ''Hylomyscus''. For example, ''H. endorobae'' can be distinguished because it is larger than ''H. denniae'', with a broader skull and larger molars.

References

{{Taxonbar, from=Q1875375 endorobae Mammals of Kenya Mammals described in 1910 Endemic fauna of Kenya