Rice is the staple food for half of the human population.It is necessary to determine the composition of its biosensors. In this work we determined, in Moroccan rice fields, the systematic structure of three families of Coleoptera (Dytiscidae, Hydrphilidae and Crarbidae) and one family (Culicidae) of the population constituting the population of the order Diptera. The qualitative sampling of the studied fauna was carried out by troubleau net every 15 days and during the 2018-2019 rice-growing campaigns. The results showed that the population concerned is systematically rich and diverse, and of palearctic, Mediterranean biogeographical origin or of wide distribution with wide geographical distribution. It is made up of 39 species divided into 15 Dytiscidae beetles, 11 Hydrophilid beetles, 7 Carabid beetles and 7 Culicid beetles. The Dyticidae family is systematically more diverse than those of hydrophilids and carabids. The genera Laccophilus, Cybister, Enochrus and Berosus are the genera most represented in species. The great abundance and the important specific diversity of coleopera and diptera could be the main factor of the entomological diversity of Moroccan rice fields.

Keywords:Coleoptera insects, Diptera insects, Specific structure, Rice fields, Morocco.