BV using pitfall traps and with special emphasis on the geographical distribution and the relationships of abundance of the Tenebrionidae assemblage, the taxonomic composition and the patterns of abundance (denso-activity) of the Arthropoda inhabiting the transect 27-30 degrees S of the chilean transitional coastal-desert were examined. Five orders numerically dominated the Arthropoda assemblage. These were Coleoptera, Diptera, Psocoptera, Collembola and Hymenoptera. Tenebrionidae, represented by 14 genera, was the most diverse and abundant family of the epigean arthropod-fauna. Gyriosomus Guerin-Meneville, 1834 was the most specious genus ill that family. Some of its species showed a narrow distribution in the study area, and may be indicators of endemisms. The species richness of Tenebrionidae did not follow the latitudinal pluviometric pattern of the transect. Carrizal Bajo, a site with xeric conditions, provided a higher number than expected. in accordance with the pattern shown by the flora, mainly geophytes and hemicryptophytes.