Patterns of genetic and phenotypic diversity of the Mediterranean banded centipede Scolopendra cingulata Latreille, 1829 (Chilopoda: Scolopendromorpha) in Sicily and adjacent areas

Abstract

The genus Scolopendra is a taxonomically complex group, with species displaying intricate evolutionary radiation across Mediterranean islands. The present work aims to explore the diversity patterns of the Mediterranean banded centipede S. cingulata across Sicily, some surrounding islands, and Southern Calabria, investigating its genetic (COI and 28S) and phenotypic variation. Through extensive sampling and the analysis of 92 COI sequences from 82 sampling sites, three distinct structured lineages were identified in the study area: Sicily/Malta (SM), Eastern Peloritani Mountains (EP), and Aspromonte (As). Conversely, 28S sequences did not reveal the same genetic structure observed in the COI, probably due to the occurrence of introgression phenomena. Morphological assessments showed significant variation among clades. Colour pattern analysis revealed distinguishable morphotypes among the three clades. SM juveniles exhibit a unique light morphotype, contrasting with the dark dichromatic morphotype common to As and EP juveniles. These findings seem to suggest multiple colonisation events and prolonged isolation periods in Sicily, which shaped the current diversity of S. cingulata on the island. The genetic distinctiveness and apparent parapatric distribution of SM and EP, with limited evidence of admixture, highlight the need for further studies to fully understand the evolutionary history and potential taxonomic implications for this taxon.