From 1941 to 1946, E. Morales Agacino (Estación Fitopatológica del INIA, Almería), accompanied by J. Mateu Sanpere (naturalist, seconded to the Spanish Sahara), J. Giner Marí (Instituto Español de Entomología, Madrid) and F. Español Coll (Museo de Zoología, Barcelona), explored the ex-Spanish Sahara (from Cap Juby to Cap Blanc) according to a standardised protocol. Collected specimens and types of newly described taxa were deposited in the museums of Madrid and Barcelona and the results of the surveys published in the journal EOS. In total, 356 species and subspecies of Polyneoptera, Coleoptera and Hymenoptera have been collected. This large-scale entomological survey is presently little considered, mainly because the published locality names are no more in use and difficult to georeference. We have reconstructed the routes of the eight missions carried out by Morales Agacino, Giner Marí and Mateu Sanpere using old maps of the Spanish Sahara (1949) and recent maps of southern Morocco. 134 collection sites have been identified, listed with old and actual toponyms, geographical coordinates and elements of topographical descriptions. Lists of the species collected during these expeditions for the Insecta Orthoptera, Blattodea, Mantodea, Dermaptera, Phasmatodea, Coleoptera (Carabidae Latreille, 1802 and Tenebrionidae Latreille, 1802), and Hymenoptera (Sphecidae Latreille, 1802, Crabronidae Latreille, 1802, Pompilidae Latreille, 1805, Bradynobaenidae Saussure, 1892 and Mutillidae Latreille, 1802) are given. The scientific value of these data for taxonomy and conservation is illustrated for the Orthoptera Acridomorpha: within the Dericorythidae Jacobson & Bianchi, 1905, the type locality of Bolivaremia domenechi Morales Agacino, 1949 is identified and described; and the synonymy of Pamphagulus mateui Morales Agacino, 1949 and Pamphagulus vicinus Ramme, 1931 is reanalysed using distributional data. Examples of acridomorph Saharan and Mediterranean indicator species are given, using their separate distributions in the local west-east climate continuum. The coherence of the surveys carried out by Morales Agacino and his collaborators provide a most valuable reference inventory for the characterization of the Sahara fauna and its transformations since 1950; its use will be facilitated by the proposed up-date of geographical data.