RODENTS OF LIBYA 165 



schousboei was treated as a subspecies of Meriones libycus by de Beaux 

 (1932) and Chaworth-Musters and Ellerman (1947) and more recently 

 regarded as a synonym of Meriones libycus libycus by Ellerman and 

 Morrison-Scott (1951). In the present study, more specimens of M. 

 caudatus are available from numerous localities throughout Libya, and 

 the taxonomic position of this jird is better understood. In addition to 

 the bushy character of the tail, as established by Thomas (1919), 

 several cranial characters are apparent (see comparisons above) which 

 clearly establish M. caudatus as a distinct species from M. libycus of 

 the Western Desert of Egypt. Its specific status is confirmed by its 

 being sympatric with populations of M. libycus from several localities 

 in coastal Libya. 



The use of the name M. caudatus for this species can only be con- 

 sidered provisional at this time. It appears to be the oldest name 

 available for the Libyan population, but extralimital material (pres- 

 ently assigned to M. libycus) that I have examined from Algeria 

 (Beni Ounif) and Iran (Khurasan, Baluchistan, and Kopet Dag 

 Mountains) indicates that the present species is widespread in dis- 

 tribution and probably occurs over large portions of both North Africa 

 and Southwest Asia. It seems almost certain that older names are 

 available, but until additional material is forthcoming and a thorough 

 revision of Meriones throughout its entire range can be undertaken, 

 the name M. caudatus must serve for the Libyan population. 



Ecological observations. This species is probably the most 

 abundant and widely distributed large rodent in Libya. These jirds 

 seem to prefer arid habitats and reach their greatest numbers in the 

 deserts of the Saharan interior. They occur sporadically, however, in 

 the coastal areas, where they are sympatric with Meriones libycus. In 

 the interior, this species prefers areas of abundant sand and is oc- 

 casionally taken in areas where large dunes are present; it is never 

 found associated with mesic habitats. 



Throughout the range in Libya, these jirds occur together with 

 many species of rodents but most frequently are taken with repre- 

 sentatives of Gerbillus gerbillus, Gerbillus pyramidum, and Gerbillus 

 amoenus. 



Meriones caudatus amplus, new subspecies 



Holotype. Adult male, skin and skull, USNM 322681, from El 

 Gatrun, Fezzan Province, Libya; obtained Jan. 8, 1962, by G. L. 

 Ranck, original no. 1245. 



Specimens examined. Twenty-three, from Fezzan: Meseguin, 8; 

 Traghen, 2; 28 km E Murzuch, 3; El Gatrun, 10 (1 skin only). 



Measurements. Averages and extremes of four adult males and 

 measurements of two adult females, 322677 and 322679, all from the 



