Reevaluation of the taxonomic Status of North African gerbils usually referred to as Gerbillus pyramidum (Gerbillinae, Rodentia): Chromosomal and biometrical data

Abstract

The chromosomal and biometrical attributes of large-sized, hairy-footed gerbils from North Africausually referred to as Gerbillus pyramidum were studied. High-resolution banding techniques as wellas external and skull biometry were used to compare specimens from Mauritania and Algeria. Allspecimens studied were characterized by the same karyotype. comprising 40 chromosomes and74 autosomal arms. Gerbils from Algeria were found to be larger than those from Mauritania formost of the skull measurements, as well as for some external measurements. Comparisons with published data from other North African countries (Senegal, Morocco. Tunisia) suggest that all the previously figured 2 n = 40 karyotypes do represent the same species, chromosomally significantly distinctfrom 2 n = 38 chromosome individuals found in Egypt and Sudan that correspond to true Gerbilluspyramidum. Based on our results and awaiting contrary evidence. we propose that the 2n = 40 chro-mosome specimens found from Senegal to Libya correspond to a unique species, for which the nameGerbillus tarabuli should be applied. This species of wide distribution in northern Africa shows an ap-parently important biometrical variability, to be related with eco-climatological variations of the en-vironment in which these populations live.