Morphological and genetic evidence support the species status of Lasioglossum angustifrons, distinct from L. punctatissimum (Hymenoptera: Halictidae)

Europe hosts a remarkable diversity of wild bees, among which the genus Lasioglossum Curtis, 1833 ranks among the
most species rich. The defi nition of the taxonomic status of many species within this genus remains challenging. In this work, we
reassessed the subspecifi c status of Lasioglossum (Hemihalictus) punctatissimum angustifrons (Vachal, 1892) through a comprehensive
analysis integrating morphology, molecular and distributional data. Phylogenetic reconstruction using a Maximum Likelihood
tree and three independent species delimitation models revealed that L. angustifrons forms a distinct and well-supported
lineage, separated from L. punctatissimum (Schenck, 1853) and related taxa by signifi cant genetic distances. Morphological
examination confi rmed stable diagnostic features, including reddish metasomal terga, fi ner punctation on the scutum, and the
specifi c appearance of the male genitalia. Lasioglossum angustifrons is mainly distributed along the coastal regions of Western
North Africa, extending to the Iberian Peninsula and Sicily, with a few inland records. Based on congruent morphological and molecular
evidence, Lasioglossum (Hemihalictus) angustifrons stat. nov. is best treated as a species than a subspecies. This revision
resolves a long-standing taxonomic ambiguity in the Lasioglossum punctatissimum complex and contributes to a more accurate
understanding of species diversity in Mediterranean halictine bees.