Exploring the Diversity of Scythrididae of Southern Italy Using DNA Barcoding (Lepidoptera: Gelechioidea)

The Scythrididae Rebel, 1901, comprises small and morphologically homogeneous microlepidoptera whose identification relies mainly on genitalia examination. In Italy, this group has been more extensively investigated than other microlepidoptera families, but molecular data remain scarce. This study aims to improve the knowledge of Scythrididae diversity in southern Italy through DNA barcoding. Twenty-nine specimens collected in Calabria and Basilicata underwent DNA barcoding, yielding 28 sequences of 602–658 bp, which clustered into 10 Barcode Index Numbers (BINs), corresponding to 10 species. Three BINs are newly created in the Barcode of Life Data System (BOLD), enriching the global reference library. Except for Scythris aspromontis Jäckh, 1978, described for the study area, the remaining species represent faunistic novelties at different scales: Scythris dissitella (Zeller, 1847) is new for continental Italy and eight additional species are new for southern Italy or Calabria and Basilicata regions. Moreover, a significant genetic distance was observed between our sequence of Scythris cf. tabidella (Herrich-Schäffer, 1855) and sequences of tabidella available on BOLD, which will be addressed in detail in the discussions. The results highlight the underexplored diversity of Scythrididae in the Mediterranean region and confirm the effectiveness of integrative taxonomy combining DNA barcoding and morphology. This study provides the first molecular contribution to the Scythrididae fauna of southern Italy and contributes to improving the taxonomic knowledge of a group that remains insufficiently investigated in the Mediterranean region.