Jelassi, Raja ， Harzalli, Nabil ， Ben Said, Amina ， Nasri-Ammar, Karima
2025-03-04 BIOLOGICAL RHYTHM RESEARCH 2025 56(卷), 3(期), (145-157页)
Tenebrionidae beetles are a conspicuous element of most arid and semi-arid environments. In this paper, the two sympatric darkling beetles' species Erodius emondi (N = 21) and Pimelia grossa (N = 21), collected from the coastal dunes of Korba, are chosen to characterize their locomotor activity rhythm under laboratory conditions under natural light-dark cycle then under constant darkness. Our results highlighted the existence of diurnal behaviour for both species with the presence of ultradian and circadian components, whatever the experimental conditions. These two species exhibited in majority multimodal activity patterns under entraining conditions. Under constant darkness, we noted the appearance, in addition to the multimodal profile, the unimodal and bimodal ones for E. emondi and P. grossa respectively. The specimens of this last species were statistically more active displaying also the most important stability of their locomotor rhythm compared to those of E. emondi. The obtained results will be discussed in relation to their temporal niches segregation.