Barcoding analysis and taxonomic revision of Goliathus Lamarck, 1802 (Scarabaeidae, Cetoniinae)

We conducted barcoding analysis of valid taxa in the genus Goliathus Lamarck, 1802 and clarified their relationships. Specimens of Goliathus goliatus (Drury, 1770) sampled in tropical rainforests from Cameroon to Kenya display degrees of genetic and phenotypic separation that, however, do not seem to justify subspecific splitting. Goliathus meleagris Sjöstedt, 1927, which is localized in the Miombo woodlands of southern Democratic Republic of the Congo, Democratic Republic of Congo, and neighbouring areas of Angola and Zambia, is raised from synonymy with Goliathus orientalis Moser, 1909 and ranked subspecifically under Goliathus goliatus status rev., bona ssp. The moderate genetic separation, the eco-geographic isolation, and the presence of transitional populations in the Maniema and Tanganyika Provinces of D. R. C., together indicate that a single species with two subspecies are involved. We also provide historical arguments and present new material indicating that the type locality of Goliathus orientalis, “landeinwärts von Lindi” is in a region between Songea and the eastern shore of Lake Malawi in southwest Tanzania. Goliathus orientalis is recognized as a good species, bona sp. and Goliathus usambarensis Preiss, 1933 (type locality: Usambara Mountains) is ranked subspecifically under it, status rev.. Goliathus regius Klug, 1835, Goliathus cacicus (Olivier 1789) and Goliathus albosignatus Boheman, 1857 are confirmed good species. Notably, Goliathus albosignatus forms a separate cluster that is equidistant from the sister genus Fornasinius Bertoloni, 1853 and the outstanding Goliathus species-group, suggesting early separation of Goliathus albosignatus from a common ancestor. All valid Goliathus taxa are illustrated.