Dufourea

Dufourea can be distinguished from other halictid genera by the low position of antennal bases on the face—well below the middle and separated from the clypeus by only slightly more than the diameter of an antennal socket. The combination of short, wide clypeus and labrum nearly as long as the clypeus further separates this genus from superficially similar taxa. The presence of a pre-episternal groove is an additional diagnostic character.

Habitat varies by species; includes alpine regions of Central Europe, limestone bluffs and hilltop prairies, dry-mesic deciduous forests, and open glades. Some species associated with specific geological formations such as dolomite glades.

Widespread distribution across multiple continents. Documented from North America (including eastern United States, Michigan, Illinois, and southern Arizona), Europe (including Iberian Peninsula and Alps), and other regions. Individual species show more restricted ranges; for example, Dufourea lusitanica is endemic to Iberia, while Dufourea harveyi has been recorded in Michigan and represents the first published record in the eastern United States.

Activity periods vary by species and region. In southern Arizona, adults have been observed in September. In temperate regions, activity generally coincides with blooming periods of host plants.

Adult females collect pollen from flowers for provisioning nests. Degree of host specialization varies among species: some are oligolectic specialists (e.g., Dufourea lusitanica and related species apparently specialized on Caryophyllaceae), while others show broader pollen host spectra.

Solitary nesting biology. Females construct and provision nests independently without cooperative social structure.

Solitary bees; females collect pollen and nectar to provision individual nest cells. Some species display oligolectic behavior, consistently visiting flowers of a single plant family or genus for pollen collection. Adults have been observed resting on flowers in inactive aggregations.

Pollinators in various ecosystems including alpine and prairie habitats. Contribution to pollination of native wildflowers, particularly in specialized plant-pollinator relationships where oligolectic species are involved.

Contributes to pollination of native flora. Subject of scientific research on bee evolution, olfactory receptor evolution, and sociality origins due to comparison with eusocial bees.

• Other Halictidae generaDufourea distinguished by low antennal base position, short wide clypeus, and pre-episternal groove; other halictids typically have antennal bases positioned higher on the face
• PanurginusMorphologically similar females distinguished by quantitative characters; both genera occur in alpine habitats and show variation in pollen host specialization

• BugGuide
• Wikipedia
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• Lepidoptera | Beetles In The Bush | Page 4
• Dufourea ( Dentirophites) in Iberia, with first records of a pollen host for Dufourea lusitanica Ebmer, 1999 (Hymenoptera: Apoidea, Halictidae)
• Bees of the genera <i>Dufourea</i> and <i>Dieunomia</i> of Michigan (Hymenoptera: Apoidea: Halictidae), with a key to the <i>Dufourea</i> of the eastern United States
• Pollen host selection by predominantly alpine bee species of the genera Andrena, Panurginus, Dufourea, Megachile, Hoplitis and Osmia (Hymenoptera, Apoidea)
• <i>Dufourea Novaeangliae</i> in Illinois, with Confirmation of Host Plant (Hymenptera: Halictidae)
• Computational genome-wide survey of odorant receptors from two solitary bees Dufourea novaeangliae (Hymenoptera: Halictidae) and Habropoda laboriosa (Hymenoptera: Apidae)