Integrative taxonomy identifies Lasioglossum fertoni (Vachal, 1895) and Lasioglossum discus (Smith, 1853) (Hymenoptera: Anthophila: Halictidae) as distinct species

The genus Lasioglossum Curtis, 1833, is one of the most diverse bee genera in Europe, with 183 described species. Recent advances in integrative taxonomy, combining morphological, molecular, and ecological data, have enhanced our understanding of cryptic and semi-cryptic species complexes within the genus. This study provides a comprehensive reassessment of the taxonomic status of L. fertoni (Vachal, 1895) stat. rev., integrating genetic, morphological, and biogeographic data. Our findings reveal clear differentiation between L. fertoni and the closely related species L. discus (Smith, 1853), supported by genetic distances and diagnostic morphological traits. The two taxa show partially overlapping ranges, although confirmed cases of syntopy remain to be demonstrated. Lasioglossum fertoni is confirmed to have a distribution across the Western Mediterranean. The study highlights the importance of integrative approaches in resolving taxonomic ambiguities and underscores the relevance of accurate species delineation for conservation efforts, particularly in light of the growing threats to European pollinators.