Groundnut,

Arachis hypogaea L., Fabaceae, occupies an important place in the diet of people in developing countries due to its high nutritional value. The worst damage is caused by a species of Coleoptera Chrysomelidae Bruchinae namely Caryedon serratus Ol., whose larvae develop in seeds by eating the cotyledons. The objective of this work was to identify different ecotypes of C. serratus subservient to groundnuts in four countries in West Africa: Senegal, Mali, Burkina Faso and Niger using the PCR‐sequencing in order to develop strategies for protection, taking into account the environment for producers. We addressed the variability of cytoplasmic genome sequencing directly into a portion of the mitochondrial cytochrome gene from 46 individuals of C. serratus sampled in the West Africa sub region. It appears that the variability of this fraction of the genome is quite strong. Several haplotypes were identified in all these countries. Phylogenetic reconstructions by parsimony, maximum likelihood and Neighbor‐joining confirmed the lack of structure of C. serratus according to distance. They also revealed that the same biotype infesting groundnuts in Senegal also infests the whole sub‐region.