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Abstract Silene spaldingii S Watson is a rare long-lived forb (Caryophyllaceae) found primarily in open native grasslands of the Inland Pacific Northwest and is putatively pollinated by one key bumble bee pollinator, Bombus fervidus (Fabricius). However, populations of bumble bees and their visitation patterns can vary dramatically, and some species are in decline including B. fervidus. Understanding the role of co-pollinators such as sweat bees (Halictidae) could be crucial as the plight of rare plants and pollinators intensifies. We collected data across three seasons (2015–2017) on the Bombus-S. spaldingii pollination system, focusing on three Key Conservation Areas in the Channeled Scablands of eastern Washington. Bee visitors to S. spaldingii were monitored and the pool-of-pollinators was surveyed with blue vane traps. Nine species of bees were observed foraging on the plant, while 2211 bees comprised of five families, 22 genera and 81 taxa were captured in blue vane traps, meaning only 11.1% of species in the pollinator pool visited S. spaldingii. Halictus tripartitus Cockerell, a sweat bee, was a common visitor to the plant, but this was the first record of visitation for several other species, including Lasioglossum buccale (Pérez) which has never before been recorded in the Americas. These sweat bees appear to vector S. spaldingii pollen, suggesting they are co-pollinators of the plant. Weather and patch characteristics affected visitation patterns and the pool-of-pollinators. We conclude that sweat bees are likely co-pollinators of S. spaldingii and that they could become increasingly important if B. fervidus populations continue to decline.

It is widely understood that bees play an important role in many different ecosystems, due to the services they provide as pollinators [...]

Abstract Species occurrence data are foundational for research, conservation, and science communication, but the limited availability and accessibility of reliable data represents a major obstacle, particularly for insects, which face mounting pressures. We present BeeBDC, a new R package, and a global bee occurrence dataset to address this issue. We combined >18.3 million bee occurrence records from multiple public repositories (GBIF, SCAN, iDigBio, USGS, ALA) and smaller datasets, then standardised, flagged, deduplicated, and cleaned the data using the reproducible BeeBDC R-workflow. Specifically, we harmonised species names (following established global taxonomy), country names, and collection dates and, we added record-level flags for a series of potential quality issues. These data are provided in two formats, “cleaned” and “flagged-but-uncleaned”. The BeeBDC package with online documentation provides end users the ability to modify filtering parameters to address their research questions. By publishing reproducible R workflows and globally cleaned datasets, we can increase the accessibility and reliability of downstream analyses. This workflow can be implemented for other taxa to support research and conservation.

Gynandromorphs are individuals that exhibit aspects of both males and females simultaneously and are the most commonly reported sexual anomalies in bees. We describe the first known specimen of a gynandromorph of the specialist pollinator Florilegus condignus (Cresson, 1878) (Hymenoptera: Apidae: Eucerini) collected in an agricultural field in northwestern Mississippi, USA. Additionally, we include and discuss phenological data from collections made in Mississippi and the Mid-Atlantic region of the United States.

Abstract Sex‐associated differences in behavior can have large ecological consequences, especially in plant–pollinator communities where floral visitor behavior affects plant reproduction. Whether these differences are prevalent enough to impact community‐level processes, however, is unknown. Using 256 plant–pollinator communities, we built networks where the floral interactions of each sex were modeled separately, comparing observations to simulated networks where sex was randomized. We found that (1) in many species the sexes differed in their network roles and visited different partners, with females tending to visit more species and more peripheral species than males; (2) more generalist species differed more in network roles between the sexes; and (3) networks where nodes were separated by sex were more specialized than simulated networks, but were similarly resistant to perturbations. These findings suggest that despite variation among species, sex‐associated differences in behavior are large enough to impact the network roles of male and female pollinators and common enough to influence the interaction patterns of entire plant–pollinator communities.

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.

In the summer of 2010, two male specimens of the neotropical orchid bee genus Eufriesea Cockerell were collected in the Guadalupe Mountains of western Texas and southeastern New Mexico, USA. We tentatively identified them as E. coerulescens (Lepeletier de Saint Fargeau) because of the uncertainty surrounding the limits of this taxon and hypothesized that they were members of a persistent bee population, rather than long-distance transient vagrants. The goals of this paper are to clarify the identity of these specimens, assess the species limits of E. coerulescens, and to evaluate suitability of habitats in the USA for this adventive species. Herein, we revise the species in the coerulescens group using morphological features of both sexes and confirm that the specimens of Eufriesea from the USA are E. coerulescens. We recognize the following six species in the coerulescens group: E. coerulescens, E. micheneri Ayala & Engel, E. simillima (Moure & Michener), which is reinstated from synonym with E. coerulescens, and three new species from Mexico (E. barthelli Gonzalez & Griswold, sp. n., E. engeli Gonzalez & Griswold, sp. n., and E. oliveri Gonzalez & Griswold, sp. n.). To facilitate the identification of these taxa, we present a fully illustrated account of the species, comparative diagnoses, descriptions, and an updated key to all Mexican species of Eufriesea. Our analyses using species distribution modelling show an absence of suitable habitat for E. coerulescens in western Texas and southeastern New Mexico, thus favoring the long-distance dispersal hypothesis. The analyses also suggest high suitability of habitats across the Caribbean and some areas in Florida, as well as in other regions in Mexico and Central America. We discuss the implications of these results and compare them with the predicted distribution available for the other two known adventive orchid bee species in the USA.

Native bees (Hymenoptera: Anthophila) were sampled using bee bowls in two states to determine biodiversity in commercial cotton fields of the southern United States. In both states, native bee communities found in cotton fields were dominated by generalist pollinators in the genera Agapostemon, Augochloropsis, Halictus, and Lasioglossum (Hymenoptera: Halictidae), and Melissodes (Hymenoptera: Apidae). Melissodes tepaneca (Cresson) was the most abundant species found in cotton fields in both states. Some species collected are known specialists on other plant taxa, suggesting they may be tourist species. Here we provide a baseline species list of native bees found in cotton. Ordination indicated separation between the communities found in the two states when pooled by genus, but these differences were not significant. While cotton is grown in highly managed and disturbed landscapes, our data suggest that a community of common generalist native pollinators persists. Many of these species are also found in other cropping systems across North America.

Interest in bees has grown dramatically in recent years in light of several studies that have reported widespread declines in bees and other pollinators. Investigating declines in wild bees can be difficult, however, due to the lack of faunal surveys that provide baseline data of bee richness and diversity. Protected lands such as national monuments and national parks can provide unique opportunities to learn about and monitor bee populations dynamics in a natural setting because the opportunity for large-scale changes to the landscape are reduced compared to unprotected lands. Here we report on a 4-year study of bees in Grand Staircase-Escalante National Monument (GSENM), found in southern Utah, USA. Using opportunistic collecting and a series of standardized plots, we collected bees throughout the six-month flowering season for four consecutive years. In total, 660 bee species are now known from the area, across 55 genera, and including 49 new species. Two genera not previously known to occur in the state of Utah were discovered, as well as 16 new species records for the state. Bees include ground-nesters, cavity- and twig-nesters, cleptoparasites, narrow specialists, generalists, solitary, and social species. The bee fauna reached peak diversity each spring, but also experienced a second peak in diversity in late summer, following monsoonal rains. The majority of GSENM’s bees are highly localized, occurring in only a few locations throughout the monument, and often in low abundance, but consistently across the four years. Only a few species are widespread and super-abundant. Certain flowering plants appear to be inordinately attractive to the bees in GSENM, including several invasive species. GSENM protects one of the richest bee faunas in the west; the large elevational gradient, incredible number of flowering plants, and the mosaic of habitats are all likely contributors to this rich assemblage of bees.

This paper describes AnthWest, a large dataset that represents one of the outcomes of a comprehensive, broadly comparative study on the diversity, biology, biogeography, and evolution of Anthidium Fabricius in the Western Hemisphere. In this dataset a total of 22,648 adult occurrence records comprising 9657 unique events are documented for 92 species of Anthidium, including the invasive range of two introduced species from Eurasia, A. oblongatum (Illiger) and A. manicatum (Linnaeus). The geospatial coverage of the dataset extends from northern Canada and Alaska to southern Argentina, and from below sea level in Death Valley, California, USA, to 4700 m a.s.l. in Tucumán, Argentina. The majority of records in the dataset correspond to information recorded from individual specimens examined by the authors during this project and deposited in 60 biodiversity collections located in Africa, Europe, North and South America. A fraction (4.8%) of the occurrence records were taken from the literature, largely California records from a taxonomic treatment with some additional records for the two introduced species. The temporal scale of the dataset represents collection events recorded between 1886 and 2012. The dataset was developed employing SQL server 2008 r2. For each specimen, the following information is generally provided: scientific name including identification qualifier when species status is uncertain (e.g. “Questionable Determination” for 0.4% of the specimens), sex, temporal and geospatial details, coordinates, data collector, host plants, associated organisms, name of identifier, historic identification, historic identifier, taxonomic value (i.e., type specimen, voucher, etc.), and repository. For a small portion of the database records, bees associated with threatened or endangered plants (~ 0.08% of total records) as well as specimens collected as part of unpublished biological inventories (~17%), georeferencing is presented only to nearest degree and the information on floral host, locality, elevation, month, and day has been withheld. This database can potentially be used in species distribution and niche modeling studies, as well as in assessments of pollinator status and pollination services. For native pollinators, this large dataset of occurrence records is the first to be simultaneously developed during a species-level systematic study.

Two new species of squash bees, Peponapis pacifica Ayala and Griswold sp. n. and P. parkeri Griswold and Ayala sp. n., are described and illustrated. Peponapis pacifica is oligolectic on flowers of Schizocarpum longisepalum (Cucurbitaceae) endemic to Mexico, where it is found in the tropical dry forest along the Pacific Coast, between Sonora and Chiapas and in the Balsas River basin; and P. parkeri is known only from the Pacific slope of Costa Rica. A key for the North and Central American species of Peponapis is provided.Se describen e ilustran 2 especies nuevas de abejas, Peponapis pacifica Ayala and Griswold sp. n. y P. parkeri Griswold and Ayala sp. n. De éstas, P. pacifica es oligoléctica sobre flores de Schizocarpum longisepalum (Cucurbitaceae), endémica de México, con distribución asociada al bosque tropical caducifolio a lo largo de la vertiente del Pacífico entre Sonora y Chiapas y en la Cuenca del río Balsas; P. parkeri es conocida sólo para la vertiente del Pacífico de Costa Rica. Se incluye una clave para las especies de América del norte y central.

New species of the rarely encountered megachilid genera Afroheriades Peters from South Africa, A. hyalinus sp. n., and Noteriades Cockerell from Myanmar and Thailand, N. jenniferae sp. n. and N. spinosus sp. n., are described and illustrated. The species are described to make their names available for forthcoming publications on phylogenetic studies of the family Megachilidae. Taxonomic notes and a comparative diagnosis for each genus are presented. Afroheriades hennigi (Peters) and A. reicherti (Brauns) are new junior synonyms of A. dolichocephalus (Friese). A key to the known species of Afroheriades is provided.

We describe females and males of Osmia (Melanosmia) calaminthae sp. n., an apparent floral specialist on Calamintha ashei (Lamiaceae), and provide observations on the behavior of female bees on flowers of this plant. We also provide diagnostic information for Osmia (Diceratosmia) conjunctoides Robertson, stat. n., and synonymize O. (Diceratosmia) subfasciata miamiensis Mitchell with O. conjunctoides syn. n. Females of both O. calaminthae and O. conjunctoides are unique among North American Osmia forshort, erect, simple facial hairs, which are apparent adaptations for collecting pollen from nototribic flowers. Osmia calaminthae is currently only known from sandy scrub at four nearby sites in the southern Lake Wales Ridge in Highlands County, Florida, USA, while O. conjunctoides is known from limited but widespread sites in the southeastern USA. We discuss the conservation status of both species based on known or speculated floral associates and distributions.

Two distinctive new species of the Neotropical stingless bee genus Paratrigona Schwarz from Ecuador and Paraguay are described and figured. The Ecuadorian species, P. scapisetosa sp. n., belongs to the haeckeli-lineatifrons group and is easily distinguished from its congeners by the unique shape and pubescence of the antennal scape, which is distinctly convex on its outer margin and bears thick, long, simple hairs along its inner margin. The Paraguayan species, P. wasbaueri sp. n., belongs to the lineata group and is easily distinguished by the pattern of body pubescence in both sexes and male genitalic characters. The male of the Mesoamerican species P. ornaticeps (Schwarz) is described and figured. New geographical records for P. impunctata and P. opaca, and an updated key to the haeckeli-lineatifrons and lineata species groups are provided.

We review the six species of non-metallic Osmia (Melanosmia) found in North America, including the description of two new species found in Canada and the northern United States: Osmia (Melanosmia) aquilonaria sp. n., and Osmia (Melanosmia) nearctica sp. n., respectively belonging to the inermis and xanthomelana species groups. We additionally provide keys to the non-metallic Melanosmia found in North America, and keys to the palearctic Melanosmia based on study of the type specimens of Osmia disjuncta Tkalců, O. ephippiata Smith, O. ishikawai Hirashima, and O. pamirensis Gussakovskij.

Megalopta Smith, 1853, is a Neotropical genus of nocturnal or crepuscular bees. Two subgenera are recognized with most of its nearly 30 species placed in the nominate subgenus. Species of Megalopta s. str. are more commonly collected than species of Noctoraptor Engel et al. 1997, all presumably parasites of Megalopta s. str. Two new species of Megalopta are described here: M. (Megalopta) tetewana, n. sp., from Mexico and M. (Noctoraptor) huaoranii, n. sp., from Ecuador. Identification keys to the Central American species of Megalopta s. str. and the species of the parasitic subgenus Noctoraptor are presented. Rev. Biol. Trop. 58 (1): 255-263. Epub 2010 March 01.Megalopta Smith, 1853, es un género Neotropical de abejas nocturnas o crepusculares. Dos subgéneros son reconocidos con la mayoría de las 30 especies ubicadas en el subgénero nominal. Las especies de Megalopta s. str. son más comúnmente recolectadas que las especies de Noctoraptor Engel et al. 1997, todas probablemente parásitas de Megalopta s. str. Aquí se describen dos especies nuevas de Megalopta: M. (Megalopta) tetewana, n. sp., de México y M. (Noctoraptor) huaoranii, n. sp., de Ecuador. Se presentan claves de identificación para las especies de Megalopta s. str. de América Central y las especies del subgénero parásito Noctoraptor.

The Rancho La Brea Tar Pits is the world's richest and most important Late Pleistocene fossil locality and best renowned for numerous fossil mammals and birds excavated over the past century. Less researched are insects, even though these specimens frequently serve as the most valuable paleoenvironemental indicators due to their narrow climate restrictions and life cycles. Our goal was to examine fossil material that included insect-plant associations, and thus an even higher potential for significant paleoenviromental data. Micro-CT scans of two exceptionally preserved leafcutter bee nest cells from the Rancho La Brea Tar Pits in Los Angeles, California reveal intact pupae dated between ∼23,000-40,000 radiocarbon years BP. Here identified as best matched to Megachile (Litomegachile) gentilis Cresson (Hymenoptera: Megachilidae) based on environmental niche models as well as morphometrics, the nest cells (LACMRLP 388E) document rare preservation and life-stage. The result of complex plant-insect interactions, they offer new insights into the environment of the Late Pleistocene in southern California. The remarkable preservation of the nest cells suggests they were assembled and nested in the ground where they were excavated. The four different types of dicotyledonous leaves used to construct the cells were likely collected in close proximity to the nest and infer a wooded or riparian habitat with sufficient pollen sources for larval provisions. LACMRLP 388E is the first record of fossil Megachile Latreille cells with pupae. Consequently, it provides a pre-modern age location for a Nearctic group, whose phylogenetic relationships and biogeographic history remain poorly understood. Megachile gentilis appears to respond to climate change as it has expanded its distribution across elevation gradients over time as estimated by habitat suitability comparisons between low and high elevations; it currently inhabits mesic habitats which occurred at a lower elevation during the Last Glacial Maximum ∼21,000 years ago. Nevertheless, the broad ecological niche of M. gentilis appears to have remained stable.

The expected invasion of the United States by Africanized honey bees has inspired long-term studies documenting the ecological importance of native and introduced bees. Baseline data are being gathered to predict the effects of the invasion. Standardized sampling procedures and tools have been developed to monitor bee communities. The studies will provide information for developing wildland area conservation policies.

A trap-nesting program in northern Spain undertaken in cooperation with Dr. Enrique Asensio (Instituto Nacional de Investigaciones Agrarias, Valladolid) over the past few years has resulted in numerous nests of megachilids. One of these represents a new species of Protosmia Ducke. It is described here in order to make the name available for the description of its nesting biology, and is named in honor of Dr. Asensio, in recognition of his considerable help in this trap-nesting study.

Historic data in the form of pinned specimens in entomological collections offer the potential to determine trends in genetic diversity of bumble bees (Bombus). We screened eight microsatellite loci in pinned bumble bee specimens from the U. S. National Pollinating Insects Collection. We tested three species (Bombus appositus, Bombus huntii and Bombus occidentalis) representing three subgenera of bumble bees (Subterraneobombus, Pyrobombus and Bombus sensu stricto) respectively. Bombus occidentalis is a species of particular concern for conservation biologists. Single mid-legs of ninety-six individuals from each species were assayed to determine microsatellite amplification success rates of historic material in a museum collection. Microsatellite alleles amplified in specimens up to 101 years old, but the rate of amplification success was significantly lower in material over 60 years of age. Loci with shorter allele sizes amplified more frequently than relatively longer alleles in samples from all age classes. We correlate the age of specimens to the age at which loci fail to amplify and discuss potential impacts of using certain markers for population genetic studies of museum specimens. [ABSTRACT FROM AUTHOR]