By amplification of pools of genomic DNA from two isolated gregarious locust populations in Africa with short decamer primers of random sequences, we identified markers which can distinguish the two major locust populations: northern Schistocerca gregaria gregaria and southern Schistocerca gregaria flaviventris. Twenty primers were examined with the genomic DNA from the two sexes of both populations. Four primers produced polymorphic patterns at low molecular weight. One primer (A2) displayed a specific amplified band with the DNA obtained from southern S. g. flaviventris locust which was not recognized in the northern S. g. gregaria. Further examination by using southern blot technique revealed that, this sequence was highly specific to the southern locusts.  It is proposed that, S. flaviventris locusts may represent an evolutionary dichotomy which took place in the African continent. The results of this study suggest that it is possible to separate the two locusts populations into two different species.