Gerbillus pyramidum E. Geoffroy Saint-Hilaire 1803

115.

Greater Egyptian Gerbil

Gerbillus pyramidum

French: Grande Gerbille / German: Grote Agypten-Rennmaus / Spanish: Gerbillo de Egipto grande

Other common names: Burton's Gerbil

113.

Principal Gerbil

Gerbillus principulus

Taxonomy. Gerbillus pyramidum E. Geoffroy Saint-Hilaire, 1803,

Giza Province, Egypt. D. M. Lay in 1983 described a high chro-mosomal polymorphism within G. pyramdum, the distribution and constitution of which were debated by many authors. Several subsequent morphometric and chromosomal studies showed that the taxon is more widely distributed in sahelian zones of West Africa than initially recognized. D. J. Osborn and I. Helmy hypothesized in 1980 that, on basis of morphologicalattributes, G. pyramidum included also G. floweri + G. perpallidus; in molecular analysis in 2016, however, A. Ndiaye and colleagues tested that theory and found that G. floweri (with G. perpallidus as a synonym) represented a separate clade from G. pyramidum. Three subspecies recognized.

French: Gerbille du Meidob / German: Jebel-Meidob-Rennmaus / Spanish: Gerbillo principal

Taxonomy. Dipodillus principulus Thomas & Hinton, 1923, El Malha, Jebel Meidob, Sudan.

Taxonomic status of G. principulus is uncertain: it was treated as a valid species by D. M. Lay in 1983 and I. Ya. Pavlinov and colleagues in 1990, whereas both D. C. D. Happold in 2013 and A. Monadjem and colleagues in 2015 did not consider it. No morphological or genetic arguments have been made, however, to declare the species incertaesedis or to favor synonymization. Because it is poorly known, and pending a general revision of East African gerbils, present treatmentfollows G. G. Musser and M. D. Carleton’s 2005 taxonomy. Monotypic.

Subspecies and Distribution.

G.p.pyramidumEGeoffroySaint-Hilaire,1803—NEgypt.

Distribution. Known only from two localities separated by a few kilometers in W Sudan.

Descriptive notes. Head-body 73 mm,tail 115 mm, ear 11 mm, hindfoot 21 mm (holotype measurements). No specific data are available for body weight. The Principal Gerbil is a medium-sized gerbil with bright sandy-buffy dorsal pelage, white patches behind eye and ear, and white forefeet and hindfeet, the hindfeet with naked soles. Tail is very long (157% of head-body length), bicolored, and ending with marked pencil of brown hairs. It has large and inflated tympanic bullae (38% of maximum length of skull).

Habitat. Arid climate where Sahara meets Sahelian savannas.

Food and Feeding. No information.

Breeding. No information.

Activity patterns. The Principal Gerbil is probably nocturnal and terrestrial.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Data Deficient on The IUCN Red Last.

Bibliography. Happold (2013a), Lay (1983), Monadjem et al. (2015), Musser & Carleton (2005), Pavlinov et al. (1990), Thomas & Hinton (1923a).

114.

Rhoads’s Gerbil

Gerbillus pulvinatus

French: Gerbille a coussinets / German: Dschibuti-Rennmaus / Spanish: Gerbillo de Rhoads

Other common names: Cushioned Gerbil

Taxonomy. Gerbillus pulvinatus Rhoads, 1896,

Rusia, Lake Rudolf, Ethiopia. Taxonomic status and constitution of G. pulvinatus have been disputed by some authors, but D. M. Lay in 1983, G. G. Musser and M. D. Carleton in 2005, D. C. D. Happold in 2013, and A. Monadjem and colleagues in 2015 considered it valid. Standard karyotype was provided by B. Hubert in 1978. Monotypic. Distribution. Djibouti, SW Ethiopia, and NW Kenya; it may occur in extreme SE South Sudan.

Descriptive notes. Head—body 86-105 mm,tail 118-145 mm, ear 10-16 mm, hindfoot 25-28 mm. No specific data are available for body weight. Chromosomal complement has 2n = 62, FN = 84. Rhoads’s Gerbil is a medium-sized to small gerbil with soles of hindfeet partly hairy. Dorsal pelage is sandy brown and ventral one pure white. Tail is long (140% of head-body length) and bicolored, with pencil of darker hairs visible at tip. Chin, throat, and feet are white.

Habitat. Arid regions of Somali-Masai savannas. Rhoads’s Gerbil has been captured in dry grasslands and sandy soils in Omo region of Ethiopia, while in Djibouti it was found among volcanic rocks covered with sparse bush and trees.

Food and Feeding. No information.

Breeding. No information.

Activity patterns. Rhoads'’s Gerbil is probably nocturnal, and terrestrial, digging burrows. Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Least Concern on The IUCN Red List. Rhoads’s Gerbil may be abundant locally, and is found in the Omo National Park in south-west Ethiopia.

Bibliography. Happold (2013a), Hubert (1978b), Lay (1983), Monadjem et al. (2015), Musser & Carleton (2005), Pearch et al. (2001), Rhoads (1896), Yalden et al. (1996).

G. p. elbaensis Setzer, 1958 — SE Egypt and NE Sudan (SE Eastern Desert).

On following pages: 116. Rupicolous Gerbil (Gerbillus rupicola); 117. Khartoum Gerbil (Gerbillus stigmonyx); 118. Berbera Gerbil (Gerbillus acticola); 119. Brockman's Gerbil (Gerbillus brockmani); 120. Dunn's Gerbil (Gerbillus dunni): 121. Mackilligin's Gerbil (Gerbillus mackilligini); 122. Least Gerbil (Gerbillus pusillus); 123. Rosalinda Gerbil (Gerbillus rosalinda); 124. Somalian Gerbil (Gerbillus somalicus); 125. Harwood's Gerbil (Gerbillus harwoodi); 126. Cheesman’s Gerbil (Gerbillus cheesmani); 127. Wagner's Gerbil (Gerbillus dasyurus); 128. Black-tufted Gerbil (Gerbillus famulus); 129. Mesopotamian Gerbil (Gerbillus mesopotamiae); 130. Balochistan Gerbil (Gerbillus nanus): 131. Large Aden Gerbil (Gerbillus poecilops); 132. Swarthy Gerbil (Gerbillus aquilus); 133. Indian Hairy-footed Gerbil (Gerbillus gleadowi); 134. Somali Pygmy Gerbil (Microdillus peel); 135. Pouched Gerbil (Desmodilliscus braueri): 136. Fat-tailed Jird (Pachyuromys duprasi); 137. Bushy-tailed Jird (Sekeetamys calurus).

G. p. gedeedus Osborn & Helmy, 1980 — known from a few oases in Egypt. Also present in W Mauritania, and from Mali E to Sudan, but subspecies involved not known.

Descriptive notes. Head-body 102-135 mm, tail 128-180 mm, ear 14-20 mm, hindfoot 30-39 mm; weight 37-67 g. Males are slightly heavier and larger than females. The Greater Egyptian Gerbilis a large gerbil with orange-brown dorsal pelage sharply delineated on flanks from pure white venter. White spots are present on head around eyes, and hands and feet are white. Long feet bear hairy soles. Long tail (125-150% of head-body length) terminates in a more orless well-marked dark hair pencil. Female has four pairs of mammae. Chromosomal complement has 2n = 38, FNa = 72.

Habitat. Sandy habitats, oases with palm plantations, coastal plains and dunes. Greater Egyptian Gerbil may be found in grasslands with Panicum turgidum (Poaceae) tussocks at base of Acacia (Fabaceae) and Tamarix (Tamaricaceae) trees. May be found also in anthropogenic habitats (e.g. edges of cultivated fields, irrigated canals, storehouses, gardens, and even houses).

Food and Feeding. The Greater Egyptian Gerbil is granivorous and herbivorous. It may store food (seeds) during wet season in orderto survive during dry season.

Breeding. In north Sudan, reproduction occurs during rainy season and dry cold season. Gestation lasts 22 days, and litter is of 2-5 young (mean 3). Juveniles are weaned at 25-30 days, and become mature in 3-4 months.

Activity patterns. The Greater Egyptian Gerbil is crepuscular and nocturnal, and terrestrial. It digs burrows with up to five entrances very similar to those of the Lesser Egyptian Gerbil (G. gerbillus), where it spends day. It may also make use of burrows of other gerbil speciesat the base of bush or trees in sandy hills.

Movements, Home range and Social organization. The Greater Egyptian Gerbil appears to be abundant and seems to be gregarious.

Status and Conservation. Classified as Least Concern on The IUCN Red List owingto its abundance and wide distribution.

Bibliography. Abramsky et al. (1994), Dobigny, Nomao & Gautun (2002), Granjon & Duplantier (2009), Granjon, Bonnet et al. (1999), Granjon, Bruderer et al. (2002), Happold (1968), Lay (1983), Musser & Carleton (2005), Ndiaye, Chevret et al. (2016), Ndiaye, Tatard et al. (2016), Osborn & Helmy (1980).