Sylvisorex isabellae


Taxonomy [top]

Kingdom Phylum Class Order Family

Scientific Name: Sylvisorex isabellae
Species Authority: Heim de Balsac, 1968
Common Name(s):
English Bioko Forest Shrew, Isabella Shrew
Taxonomic Notes: Sylvisorex isabellae possibly represents two similar, but distinct, species. Further studies are needed to clarify the taxonomic status of the two populations currently allocated to this species.

Assessment Information [top]

Red List Category & Criteria: Endangered B1ab(iii) ver 3.1
Year Published: 2008
Date Assessed: 2008-06-30
Assessor(s): Hutterer, R. & Howell, K.
Reviewer(s): Amori, G. (Small Nonvolant Mammal Red List Authority) & Cox, N. (Global Mammal Assessment Team)
Listed as Endangered because its extent of occurrence is less than 5,000 km², all individuals are in fewer than five locations, and there is continuing decline in the extent and quality of its habitat.
2004 Endangered
1996 Vulnerable

Geographic Range [top]

Range Description: This species is known only with certainty from the northern peak of Bioko Island, Equatorial Guinea. A similar population of Sylvisorex of unsolved taxonomic status occurs in the Bamenda Highlands of Cameroon. This might be a distinct species, but appears to be morphologically very similar to Sylvisorex isabellae. It has been recorded up to 2,000 m asl on Bioko.
Equatorial Guinea (Bioko)
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population: This is an uncommon species, known from only a few specimens.
Population Trend: Decreasing

Habitat and Ecology [top]

Habitat and Ecology: This species is present in montane tropical moist forest, and grasslands found above the treeline.
Systems: Terrestrial

Threats [top]

Major Threat(s): This species is threatened by habitat loss largely resulting from logging operations, and the conversion of land to agricultural use.

Conservation Actions [top]

Conservation Actions: There are no direct conservation measures in place for this species. This species is present in the Mount Oku Faunal Reserve in Cameroon. There is an urgent need to conserve suitable montane forest habitat for this species, most especially on Bioko. Additional studies are needed into the taxonomy, distribution, abundance, general ecology and threats to this little-known species.

Citation: Hutterer, R. & Howell, K. 2008. Sylvisorex isabellae. The IUCN Red List of Threatened Species. Version 2015.2. <>. Downloaded on 05 September 2015.
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