Psammomys obesus Cretzschmar 1828

Psammomys obesus Cretzschmar, 1828

Common name: Fat sand rat.

Diagnosis: Large rodent. Fur dorsally sandy to yellowish in color, ventral side grayish white, line of demarcation not very distinct (Figure 62). No white patches behind ears or above eyes. Ears densely haired and short. Feet with black claws. Long hair on hindfeet soles, with naked heel. Tail short and thick terminating with a black tuft. Skull robust and very angular with well-developed ridges. Upper incisors without grooves, else the crown structure of molars very similar to Meriones (Figure 63).

Localities: Previous records. Al Muwaqqar (Amr & Saliba, 1986); Al Muwaqqar, Qaşr al Ḩallābāt, 60 km S ‘Ammān (Amr & Disi, 1988); 20 km NW El Quweira, Wādī Ramm (Abu Baker & Amr, 2004); Ḑānā Biosphere Reserve (Yousef & Amr, 2005). New records. Al-Hassa, Al Jafr, Al Lajjun, Al Qaţrānah, Ash Shawmarī Nature Reserve, ‘Aqaba, Azraq, Dhaba’ah, Jabal Masuda, Ma'an, Swaqa, Umm ar Rasas (Figure 64).

Habitat: The ecology of this species was studied by Amr & Saliba (1986), where they reported on its diurnal activity, feeding habits, burrow system and association with other animals. The fat sand rat is a colonial species forming large colonies constructed close to Anabasis sp. shrubs. It was found to share burrow with the Syrian hamster. In some areas, previously known to harbor dense colonies of this jird disappeared entirely; where as new colonies are established in new areas away from the original foci. Distribution of this species is associated with the presence of chenopods (i.e. Anabasis articulata, A. syriaca etc).

Biology: Gestation period may last for 23–25 days, and females give birth to 2–8 young (Osborn & Helmy, 1980).

Remarks: This is another important reservoir animal for human leishmaniasis, a disease known in Jordan and associated with areas colonized by this jird. The karyotype for specimens collected from Jordan yeiled 2n=48 and FN=74, 75 with 18 acrocentric or telocentric and 28 biarmed autosomes (Qumsiyeh et al., 1986).