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The identification of females of Agapostemon angelicus Cockerell and A. texanus Cresson has been a longstanding problem, with females of the two species considered morphologically indistinguishable. Prompted by recent collections in Minnesota that unexpectedly revealed the presence of A. angelicus as well as a cryptic form of A. texanus, we reassess the taxonomy of the “doubly punctate” Agapostemon species in both Minnesota and the broader United States. Examination of both new and old specimens has allowed us to identify A. angelicus females morphologically, and we reinstate A. subtilior Cockerell stat. rev. from synonymy with A. texanus. We recognize a number of new synonyms of A. subtilior that were formerly considered synonyms of A. texanus: A. borealis Crawford syn. nov., A. californicus Crawford syn. nov., A. texanus vandykei Cockerell syn. nov., A. californicus psammobius syn. nov., A. angelicus idahoensis syn. nov., and A. californicus clementinus syn. nov. We provide keys and diagnoses to allow for morphological identification of A. angelicus, A. subtilior, and A. texanus. We show that A. texanus s. s. has a relatively restricted range in the prairie region of the United States, with A. subtilior making up the bulk of what was formerly considered A. texanus. We further show that A. angelicus has a more extensive range than previously thought. Additional work remains, as there are a number of gaps in the known ranges of these species and more taxonomic work is required in the A. texanus complex south of the United States.

Augochloropsis and other shiny green Halictinae have had various taxonomic issues and are often misidentified. One prevailing taxonomic issue is that Augochloropsis metallica (Fabricius) has two subspecies, that have long been recognized as morphologically distinct (Augochloropsis metallica metallica and Augochloropsis metallica fulgida (Smith), but the subspecies are inconsistently applied in the literature. Here, we review the Augochloropsis of the Midwest and further address the Augochloropsis species in the broader United States to resolve the outstanding taxonomic issues with the midwestern species. We provide identification keys and diagnoses for the genera and species of the shiny green Halictinae of the midwestern United States, which includes the genera Agapostemon, Augochlora, Augochlorella, and Augochloropsis. This work results in taxonomic changes to Augochloropsis. Augochloropsis sumptuosa (Smith) is split into two species, with the name Augochloropsis sumptuosa retained for the eastern form, and Augochloropsis humeralis (Patton), stat. nov., reinstated for the western form. Augochloropsis metallica is split into five species, with two of those species occurring in the midwestern United States: Augochloropsis metallica and Augochloropsis viridula (Smith), stat. nov. Examination of the holotype of Augochloropsis fulgida (Smith) revealed that it does not agree with the prevailing concept of Augochloropsis metallica fulgida; it is reinstated as Augochloropsis fulgida, stat. nov., but is currently known only from the holotype female from Florida. Augochloropsis cuprea (Smith), long considered to be a synonym of Augochloropsis metallica, is also distinct, and we are reinstating Augochloropsis cuprea, stat. nov., though the range of this species is unclear. We further recognize Augochloropsis fulvofimbriata (Friese), stat. nov., from South and Central America, as distinct. These changes result in a total of three Augochloropsis species in the Midwest and seven named species in the United States. We are aware of additional species from the southern and southwestern United States that are undescribed, and we highlight additional taxonomic work that remains to be done.

Abstract Network analyses rarely include fitness components, such as germination, to tie invasive plants to population‐level effects on the natives. We address this limitation in a previously studied network of flower visitors around a suite of native and invasive plants that includes an endemic plant at Badlands National Park, South Dakota, USA. Eriogonum visheri coflowers with two abundant invasive plants, Salsola tragus and Melilotus officinalis, as well as a common congener, E. pauciflorum. Network analyses had suggested strong linkages between E. visheri and S. tragus and E. pauciflorum, with a weaker link to M. officinalis. We measured visitation, pollen deposited on stigmas, achene weight and germination over three field seasons (two for germination) in four populations (two in the final season) of E. visheri and applied in situ pollen treatments to E. visheri, adding pollen from other flowers on the same plant; flowers on other E. visheri plants; S. tragus, M. officinalis, or E. pauciflorum; open pollination; or excluding pollinators. Insect visitation to E. visheri was not affected by floral abundance of any of the focal species. Most visitors were halictid bees; one of these (Lasioglossum packeri) was the only identified species to visit E. visheri all three years. Ninety‐seven percent of pollen on collected E. visheri stigmas was conspecific, but 22% of flowers had >1 grain of E. pauciflorum pollen on stigmas and 7% had >1 grain of S. tragus pollen;

Pollen is the primary protein and nutrient source for bees and they employ many different behaviors to gather it. Numerous terms have been coined to describe pollen gathering behaviors, creating confusion as many are not clearly-defined or overlap with existing terms. There is a need for a clear yet flexible classification that enables accurate, succinct descriptions of pollen gathering behaviors to enable meaningful discussion and comparison. Here, we classify the different pollen gathering behaviors into two main classes: active and incidental pollen collection. Active pollen collection is subdivided into six behaviors: scraping with the extremities, buzzing, rubbing with the body and/or scopae, rubbing with the face, tapping, and rasping. In addition to the active and incidental pollen gathering behaviors, many bees have an intermediate step in which they temporarily accumulate pollen on a discrete patch of specialized hairs. Each behavior is described and illustrated with video examples. Many of these behaviors can be further broken down based on the variations found in different bee species. Different species or individual bees mix and match these pollen collecting behaviors depending on their behavioral plasticity and host plant morphology. Taken together, the different behaviors are combined to create complex behavioral repertoires built on a foundation of simple and basic steps. This classification sets the groundwork for further research on various topics, including behavioral plasticity in different species, comparisons between generalists and specialists, and the relative effectiveness of different pollen gathering behaviors.

A systematic study of Perdita subgenus Procockerellia Timberlake and the related subgenus Allomacrotera Timberlake results in the synonymy of the latter with the former, and two specific synonymies: Perdita (Hexaperdita) glamis Timberlake is a junior synonym of Perdita (Procockerellia) stephanomeriae Timberlake, while Perdita (Procockerellia) brachyglossa Timberlake is a junior synonym of Perdita (Cockerellia) imbellis Timberlake. Perdita (Procockerellia) moldenkei Timberlake is moved to subgenus Cockerellia Ashmead. A revised subgeneric diagnosis and key to the three included species are provided. Diagnoses of species are updated with novel characters; distributions and biological data are expanded. A gynandromorph of P. (Procockerellia) moabensis Timberlake, the first known in the genus Perdita, is reported.