11.

John’s SpinyMouse

Acomys johannis

French: Acomys de John / German: John-Stachelmaus / Spanish: Raton espinoso de John

Taxonomy. Acomys johannis Thomas, 1912,

“RKabwir, 2700’ [= 823 m],” Bauchi Plateau, North Nigeria.

Acomys johannis was initially included in A. cahirinus or A. cineraceus . It was rehabilitated based on cytogenetic analyses and pelage color;its karyotype (2n = 66-68, FN = 66-72) and external, cranial, and dental characteristics differ from A. chudeaui . Molecularly, it belongs to the A. cahirinus — dimidatus species complex. Its distribution was long thought to be restricted to Bauchi Plateau in Nigeria, but molecular analysis found it comparable to specimens from Niger, Chad, Benin, northern Nigeria, and northern Cameroon, considerably extending its distribution. There is still doubt about the Burkina Faso population attributed to an undetermined species with cytochromeb analyses and incorporated to A. johannis on the basis of the same karyotype. Size and pelage color vary somewhat in Burkina Faso; brown southern individuals were significantly larger than gray-rufous northern individuals. L.. A. Lavrenchenko and colleagues in 2011 described a cytotype with 2n = 68, FN = 66 from lowland savannas of Ethiopia that could represent an eastward extension ofthe distribution of A. johannis . Monotypic.

Distribution. W Africa in Sudanian savannas S & W of the Niger River (Mali, Burkina Faso, Niger, N Ghana, N Togo, and N Benin); also recorded in N Nigeria, N Cameroon, and S Chad.

Descriptive notes. Head-body 95-123 mm, tail 85-115 mm, ear 15-19-5 mm, hindfoot 16-19-5; weight 26-60 g. John’s Spiny Mouse is brown-gray on back, is slightly more rufous on flanks, and has a pure white belly. Spiny hairs occur on back. Nasals of the skull are long and narrow. Females have three pairs of mammae.

Habitat. Rocky dry environments (isolated rocky peaks or inselbergs, cliffs, and rocky hills) and also dense vegetation near river beds.

Food and Feeding. Captive John’s Spiny Mice are omnivorous.

Breeding. In Nigeria, pregnantJohn’s Spiny Mice were found at the end of dryseason, and mean number of embryos was 1-4/female (range 1-2). In Burkina Faso, Mali, and Niger females had 2-3 embryos.

Activity patterns. John’s Spiny Mouse is nocturnal and spends the day in rock crevices or termite mounds.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Least Concern on The IUCN Red List. John’s Spiny Mouse can be locally abundant.

Bibliography. Baréme et al. (2000), Gautun et al. (1986), Granjon (2013a), Granjon & Duplantier (2009), Granjon et al. (2004), Happold (1970b), Lavrenchenko et al. (2011), Musser & Carleton (1993, 2005), Rosevear (1969), Setzer (1975), Sicard &Tranier (1996), Sokolov et al. (1993).