Beetles diversity and distribution in Vulcano Island (Sicily: Aeolian Archipelago)

The ongoing biodiversity disappearance on islands worldwide is alarming. Without an accurate biodiversity assessment, it is impossible to stop the loss of the world’s islands irreplaceable natural heritage. To assess biodiversity in terrestrial habitats, beetle monitoring is pivotal. Volcanic islands in Archipelagos can be considered oceanic islands at different ontogenetic phases, which are very useful for studying the dynamics of colonization and extinction in different beetle species. This research updates the current knowledge of the beetle species living on Vulcano Island (Aeolian Archipelago). The results of the study summarizes bibliographic data in conjunction with the specimens recently collected. The specimens collected during the research belong to 267 species, 119 of which are new records on Vulcano Island. Together with the unpublished data from private collections, a total of 138 species are reported for the first time on Vulcano Island. Among these, 76 species and 14 genera are new records in the Aeolian Archipelago, with six families of beetles never previously reported on Vulcano. These include Ciidae (also a new record from the Archipelago), Ptiliidae, Scraptiidae, Leiodidae, Eucinetidae, and Dytiscidae. The Lyctinae (Bostrichidae) are recorded for the first time in the Aeolian Archipelago. Uloma culinaris (Linnaeus, 1758) is the first Tenebrionidae of the tribe Ulomini recorded in the Aeolian Archipelago. Members of the Dermestidae of the Thorictinae and Attageninae subfamilies, were recorded for the first time on Vulcano Island. The number of beetle species known on Vulcano Island thus rises to 551, matching that of Lipari, which has the highest number of species for a single island in the Archipelago. The total number of beetle species in the Aeolian Archipelago is currently 940. Five endemic and subendemic species are new records for Vulcano: the Italian endemic Pseudomeira obscura (A. Solari and F. Solari, 1907), the Italian subendemic Enoplium doderoi Luigioni, 1926, the Sicilian endemics Dichillus subtilis Kraatz, 1862 and Pachybrachis siculus Weise, 1891, the northeastern Sicilian endemic Caulostrophus zancleanus Pesarini et Baviera, 2006. The Latridiidae species Dienerella elegans (Aubé, 1850) and the Bostrichidae Lyctus brunneus (Stephens, 1830) were reported for the first time from Sicily. The Neotropical Nitidulidae Phenolia picta (MacLeay, 1825) is recorded for the second time from Italy and is the first Nitidulinae recorded on Vulcano. One of the commonly collected species, rapidly spreading in the Mediterranean, is the imported Ozognathus cornutus (LeConte, 1859), confirmed on Vulcano Island. This extremely polyphagous species was reared, for the first time, from carpophores collected from various species of trees. Three Sicilian endemic species need to be excluded from the fauna of Vulcano: Otiorhynchus (Arammichnus) ocellifer Reitter, 1912, Anoxia (A.) scutellaris sicula Motschulsky, 1860, and Protaetia (Potosia) hypocrita (Ragusa, 1905).