Morphological Variation Within Populations of Darkling Beetles Pimelia carinata Solier, 1836 (Coleoptera: Tenebrionidae) Inhabiting in Different Regions in Egypt

Document Type : Original Article


Department of Zoology, Faculty of Science, Al Azhar University, Nasr City, Cairo, Egypt.


Most eukaryotic animals described in the world are insects. However, studies of morphometric measurements, isolation, and habitat differences are still very few for insects, especially desert insects. This study aimed to compare measurements of morphological traits of dissimilar Pimelia carinata populations as darkling beetle models in the Egyptian desert. A morphometric variations variable comparison was taken by a micrometer microscope for samples of 6 ecoregions from Egypt including; the Western Coastal Desert, El-Faiyum depression, oases of the Western Desert, Eastern Desert, Delta, and south Sinai. Morphological measurements depend upon twenty-one traits that were studied, using cluster analysis and principal component analysis to distinguish the different traits of populations. The first and second of the discriminant scores (Score 1 and Score 2) were registered at 77.64% and 24.61% of the complete variation in different samples. Multiple discriminant analyses detected clear morphometric variations between the populations of Western Desert, and Western Coastal Desert in the first cluster. while the second cluster comprises of Eastern Desert, El-Faiyum, and Nile Delta. The population of Sinai is present in a separate cluster. The traits showing maximum variability across beetle populations were those associated with morphological estimates.