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Complementarity between species in the use of flower resources can enhance the pollination services of diverse pollinator communities. To test for complementarity, we studied fine-scale patterns of flower visitation and contribution to seed set of the three locally dominant bee species (commercially managed honeybees and two wild, non-managed Lasioglossum species) visiting confection (non-oil) sunflower in central Israel. The three species differed in their temporal (time of day) and phenological (head bloom stage) visitation patterns but generally showed niche redundancy. Moreover, honeybees strongly outperformed the wild species in both visitation rates and single-visit contributions to seed set. We conclude that the present communities and densities of wild bees do not complement honeybee sunflower pollination in the studied system. Sunflower seed production in central Israel is currently dependent solely upon the high stocking rate and pollination efficiency of honeybees. [ABSTRACT FROM AUTHOR]

Andrena is one of the most diverse bee genera, comprising about 1,600 described species of ground-nesting solitary bees. Many Andrena species are plant specialists, and several taxa have been indicated to be important pollinators of wild and/or crop plants. The Eastern Mediterranean Basin and Israel in particular are one of the main world diversity hotspots of Andrena. Based on extensive examination of museum specimens combined with DNA barcoding, we hereby describe twenty-five Levantine species of Andrena new to science: Andrena anathema Pisanty sp. nov., A. ardentia Pisanty sp. nov., A. asluji Pisanty sp. nov., A. curviocciput Pisanty & Wood sp. nov., A. dividicincta Pisanty sp. nov., A. dorchini Pisanty sp. nov., A. euphorbiae Pisanty sp. nov., A. gageae Wood & Pisanty sp. nov., A. herodesi Pisanty & Wood sp. nov., A. hulae Pisanty sp. nov., A. igraeca Pisanty & Wood sp. nov., A. inusitata Pisanty sp. nov., A. janthinoides Pisanty sp. nov., A. longistilus Pisanty & Wood sp. nov., A. lunaris Pisanty & Wood sp. nov., A. macula Pisanty & Wood sp. nov., A. obtusa Pisanty sp. nov., A. ornithogali Pisanty & Wood sp. nov., A. petrae Wood sp. nov., A. protuber Pisanty sp. nov., A. sulfurea Wood sp. nov., A. turmalina Pisanty & Wood sp. nov., A. veronicae Pisanty & Wood sp. nov., A. veterana Pisanty sp. nov., and A. xera Pisanty sp. nov. We synonymise Andrena edentula Wood with A. tadauchii Gusenleitner syn. nov., and recognise four infraspecific names as valid species: Andrena mediterranea Pisanty & Scheuchl stat. nov., A. mizorhina Warncke stat. nov., A. noacki Alfken sp. resurr. and A. ochraceohirta Alfken sp. resurr. We additionally describe the hitherto unknown sexes of four species, provide new records for fifteen species previously unknown from Israel, and list fourteen taxa whose previously reported presence in Israel is considered erroneous or questionable.

Wild pollinators, bees in particular, may greatly contribute to crop pollination and provide a safety net against declines in commercial pollinators. However, the identity, life history traits, and environmental sensitivities of main crop pollinator species.have received limited attention. These are crucial for predicting pollination services of different communities and for developing management practices that enhance crop pollinators. We sampled wild bees in three crop systems (almond, confection sunflower, and seed watermelon) in a mosaic Israeli Mediterranean landscape. Bees were sampled in field/orchard edges and interiors, and in seminatural scrub surrounding the fields/orchards. We also analyzed land cover at 50-2500 m radii around fields/orchards. We used this data to distinguish crop from non-crop pollinators based on a set of life history traits (nesting, lecty, sociality, body size) linked to habitat preference and crop visitation. Bee abundance and species richness decreased from the surrounding seminatural habitat to the field/orchard interior, especially across the seminatural habitat-field edge ecotone. Thus, although rich bee communities were found near fields, only small fractions crossed the ecotone and visited crop flowers in substantial numbers. The bee assemblage in agricultural fields/orchards and on crop flowers was dominated by ground-nesting bees of the tribe Halictini, which tend to nest within fields. Bees' habitat preferences were determined mainly by nesting guild, whereas crop visitation was determined mainly by sociality. Lecty and body size also affected both measures. The percentage of surrounding seminatural habitat at 250-2500 m radii had a positive effect on wild bee diversity in field edges, for all bee guilds, while at 50-100 m radii, only aboveground nesters were positively affected. In sum, we found that crop and non-crop pollinators are distinguished by behavioral and morphological traits. Hence, analysis of life-history traits of bee communities can help assess the pollination services they are likely to provide (when taking into account single-visit pollination efficiency). The ecotone between agricultural fields and surrounding habitats is a major barrier that filters many bee species, particularly with regard to their nesting requirements. Thus, greater attention should be given to management practices that encourage pollinators to live and nest, and not only forage, within fields.