Available studies of the earthworm fauna of Corsica reported a total of 36 species, but this regional diversity is probably underestimated considering the relatively modest sampling efforts achieved so far. We conducted a sampling campaign in the context of the program “Our Planet Reviewed”, with the aim to increase sampling coverage and to analyze already known regional diversity with a combination of classical morpho-anatomic characters and DNA barcoding. We sampled a total of 31 locations, and identified 22 previously recorded species and eight new citations belonging to the families Acanthodrilidae Claus, 1880, Hormogastridae Michaelsen, 1900 and Lumbricidae Rafinesque-Schmaltz, 1815. We obtained 525 COI barcodes which clustered into 48 genetic lineages, highlighting the importance of molecular techniques for earthworm diversity surveys. Of these lineages, ten are supported by multiple lines of evidence and will be described in a forthcoming taxonomy paper as species new to science. Biogeographical affinities of the identified species showed a lower rate of cosmopolitan species compared to other Mediterranean islands, a certain degree of affinity with Italy and Sardinia, and a high rate of endemism (which could be mirrored by the Balearic Islands and Sardinia). Comparative phylogeographic analyses are needed to understand the history of colonization and diversification of earthworms on Mediterranean islands, and to investigate the drivers that shaped differences in their diversity.
Acanthodrilidae, Hormogastridae, Lumbricidae, DNA barcoding, endemism, Mediterranean islands, species list, new records