Ricerc@Sapienza

Although research on human-mediated exchanges of species has substantially intensified
during the last centuries, we know surprisingly little about temporal dynamics of alien species
accumulations across regions and taxa. Using a novel database of 45,813 first records of
16,926 established alien species, we show that the annual rate of first records worldwide has
increased during the last 200 years, with 37% of all first records reported most recently
(1970–2014). Inter-continental and inter-taxonomic variation can be largely attributed to the

This work investigates the genetic identity of Hierophis viridiflavus s.l. specimens from insular populations, to determine which of the two previously identified species is present on each island. Here, the authors hypothesise about times and modes of colonization and discuss the faunistic value of the obtained results. This follows the recent proposal to consider the two clades as two different species. Specimens from the islands of Favignana, Lipari and Vulcano belong to H. carbonarius and probably all belong to putative Sicilian source populations.