RODENTS OF LIBYA 33 



Several subspecies of genetically plastic species are distributed over 

 wide geographic areas in Libya and do not conform to faunal areas 

 and provinces. These Libyan subspecies, which occur in more than 

 one faunal area, are: Gerbillus amoenus vivax; Gerbillus campestris 

 dodsoni; Gerbillus gerbillus psammophilous; Meriones crass us tripolius, 

 and Acomys cahirinus viator. 



Gerbillus campestris dodsoni occupies the largest range of any sub- 

 species of Libyan rodent and is found in all four provinces of the 

 Saharan and Saharan Steppe Faunal Areas. In the Fezzan and southern 

 Cyrenaica, this subspecies is largely confined to the oases where it is 

 usually concentrated in the more mesic portions. In the Tripolitanian 

 steppe and the Gebel Nefusa, it is almost always confined to rocky 

 habitats. Less commonly, members of this subspecies occur in sandy 

 habitats. By virtue of this apparent wide ecological tolerance, G. c. 

 dodsoni is able to occupy this large geographic area. 



The species Gerbillus amoenus and Meriones crassus require similar 

 habitats and have almost identical ranges in Libya, including the 

 Libyan Fezzan and portions of the Tripolitanian steppe. Each is 

 represented in Libya by a single subspecies. 



The range of Gerbillus gerbillus psammophilous includes a vast area 

 in Cyrenaica extending from the interior oases of Tazerbo and Bir el 

 Harasc to the margins of the coastal plain. Representatives of this 

 subspecies occur near Agedabia on the inner margins of the Cyrenaican 

 coastal plain, at Gasr es Sahabi in the Cyrenaican steppe, and at Gialo, 

 which is one of the northernmost of the Libyan Saharan oases. The 

 range of this subspecies includes portions of all three major Libyan 

 faunal areas. 



In Libya, the spiny mouse, Acomys cahirinus viator, is known from 

 three widely separated localities which include El Giof of Cufra Oasis 

 in southern Cyrenaica, the oases of Socna and Bir Fergian of south- 

 eastern Tripolitania, and the oasis of El Barcat in the Fezzan. It is 

 doubtful that populations of these mice having such a strikingly dis- 

 continuous distribution (polytopic) actually belong to the same sub- 

 species. Until larger series become available from more localities in 

 Libya and permit a more accurate analysis of the morphological 

 characters of these spiny mice, their taxonomic status should be 

 considered provisional. 



The house mouse, Mus musculus, is the most widespread of Libyan 

 rodents and is the only species which occurs in all faunal areas and 

 provinces. These mice occur as commensals in many coastal cities and, 

 by the agency of man, have colonized almost all of the isolated oases 

 of Cyrenaica and the Fezzan. They occur also as wild or feral popula- 

 tions in almost every type of habitat. On the coastal plain and the 

 Cyrenaican Plateau, where the vegetative cover is relatively uniform 

 and dense, house mice are practically ubiquitous. In the more arid 



