Álvaro Wille Trejos

The solitary oil-collecting bees of the tribes Centridini, Tapinotaspidini, and Tetrapediini inhabit areas from the southern part of the Nearctic Region through the Patagonian in southern South America, including the Caribbean. These bees are morphologically and behaviorally specialized in collecting oils as a reward from specialized floral glandular structures present in oil-producer plants. Oil-producer plants and oil-collecting bees have a mutualistic relationship in which the latter potentially pollinate the formers while collecting oils from their flowers. The main objective of this work is to infer the species richness and the key areas for conservation, research, and sustainable use of oil-collecting bees of the tribes Centridini, Tapinotaspidini, and Tetrapediini in the Americas. We collected occurrence records for 528 species of oil-collecting bees and estimated the species richness for each tribe and genus. In total, we estimated 664 species across the three mentioned tribes. With that baseline information, we created models of the richness and rarity patterns of the entire group of species and each tribe as a criterion to highlight key areas, along with richness and rarity centers for the American oil-collecting bees. We identified several critical areas that can be prioritized for conservation and research projects, including territories in Panama, Costa Rica, the Central and Northern Andes, the Amazon basin, and the biogeographic provinces of Cerrado, Atlantic Forest, Pampean, and Chacoan. Here we provide crucial information on key diversity areas for oil-collecting bees across the Americas. This information can be used for the conservation, research, and sustainable use of this important group of insect pollinators.

The stingless bees, Tetragonisca angustula (Latreille, 1811), have a large habitat distribution across Central and South America. These bees are considered beneficial for plant pollination and honey production. This study aims to identify the significant environmental factors affecting the distribution of these bees and the potential effects of future climatic conditions on their distribution. To achieve this objective, the study employed a modeling approach based on MaxEnt, GIS, and DIVA-GIS, using six environmental variables based on temperature and precipitation, and two future climate models for 2050: The Beijing Climate Center Climate System Model (BCC-CSM2-MR) and model Earth System Model2 (CMCC-ESM2). The model’s performance was high, as the area under the curve was 0.965±0.003, and the true skill statistic was 0.64, indicating the accuracy of the outputs. The results revealed a high restriction of these bees to their native distribution and the suitability of some regions outside their native range. The study found annual precipitation to be highly important for T. angustula and suggests a limited potential invasion to other regions in the near future.

This paper presents an exploratory study on the taxonomic diversity of pre-Hispanic archaeofaunas in the South-Central Andes (SCA; western South America) from the Pleistocene-Holocene boundary to the Late-Holocene. The SCA is a complex of diverse environments and has undergone distinct climate events for the last 13,000 years, such as the occurrence of warmer and drier conditions in the Middle-Holocene. The South-Central Andean area was part of the larger Andes interaction area, which was a primary center for animal and plant domestication and the emergence of agro-pastoralist economies. Since subsistence was key to these processes, the SCA provides a relevant case study on the interactions among environment, foodways and sociocultural evolution. Taxonomic diversity was used here as a proxy for diet breadth. A total of 268 archaeofaunal assemblages were sampled from the zooarchaeological literature. Reviewed variables included the cultural chronology and spatial coordinates of the assemblages, as well as the presence and abundance of taxa at the family rank. Taxonomic diversity covered two dimensions: composition (families present in each assemblage) and structure (quantitative relationships among taxa), which was measured through richness (NTAXA), ubiquity and relative abundance (NISP based rank-order). Despite the uneven distribution of samples, the analyses revealed the following trends: (1) a moderate relationship between NTAXA and distance from coastline for most of the Holocene; (2) a potential decrease in assemblage richness for coastal ecoregions during the Late-Holocene; and (3) a generalized increase in the relative abundance of Camelidae.

Abstract Ninetinae are a group of poorly known spiders that do not fit the image of ‘daddy long-legs spiders’ (Pholcidae), the family to which they belong. They are mostly short-legged, tiny and live in arid environments. The previously monotypic Andean genus Nerudia exemplifies our poor knowledge of Ninetinae: only seven adult specimens from two localities in Chile and Argentina have been reported in the literature. We found representatives of Nerudia at 24 of 52 localities visited in 2019, mostly under rocks in arid habitats, up to 4450 m a.s.l., the highest known record for Pholcidae. With now more than 400 adult specimens, we revise the genus, describing ten new species based on morphology (including SEM) and COI barcodes. We present the first karyotype data for Nerudia and for its putative sister-genus Gertschiola. These two southern South American genera share a X1X2X3Y sex chromosome system. We model the distribution of Nerudia, showing that the genus is expected to occur in the Atacama biogeographic province (no record so far) and that its environmental niche is phylogenetically conserved. This is the first comprehensive revision of any Ninetinae genus. It suggests that focused collecting may uncover a considerable diversity of these enigmatic spiders.

Aim Aggregated species occurrence data are increasingly accessible through public databases for the analysis of temporal trends in the geographic distributions of species. However, biases in these data present challenges for statistical inference. We assessed potential biases in data available through GBIF on the occurrences of four flower-visiting taxa: bees (Anthophila), hoverflies (Syrphidae), leaf-nosed bats (Phyllostomidae) and hummingbirds (Trochilidae). We also assessed whether and to what extent data mobilization efforts improved our ability to estimate trends in species' distributions. Location The Neotropics. Methods We used five data-driven heuristics to screen the data for potential geographic, temporal and taxonomic biases. We began with a continental-scale assessment of the data for all four taxa. We then identified two recent data mobilization efforts (2021) that drastically increased the quantity of records of bees collected in Chile available through GBIF. We compared the dataset before and after the addition of these new records in terms of their biases and estimated trends in species' distributions. Results We found evidence of potential sampling biases for all taxa. The addition of newly-mobilized records of bees in Chile decreased some biases but introduced others. Despite increasing the quantity of data for bees in Chile sixfold, estimates of trends in species' distributions derived using the postmobilization dataset were broadly similar to what would have been estimated before their introduction, albeit more precise. Main conclusions Our results highlight the challenges associated with drawing robust inferences about trends in species' distributions using publicly available data. Mobilizing historic records will not always enable trend estimation because more data do not necessarily equal less bias. Analysts should carefully assess their data before conducting analyses: this might enable the estimation of more robust trends and help to identify strategies for effective data mobilization. Our study also reinforces the need for targeted monitoring of pollinators worldwide.

Animal trade, such as birds, mammals and reptiles, is a common human activity. Among insects, few are as charismatic as bees. Their hives are commonly commercialized for multiple purposes, such as honey production, crop pollination and leisure. However, hive trade has the potential to adversely intr…

Aim: Due to the sessile nature of flowering plants, movements to new geographical areas occur mainly during seed dispersal. Frugivores tend to be efficient dispersers because animals move within the boundaries of their preferable niches, so seeds are more likely to be transported to environments tha…

The Amazon has high biodiversity, which has been attributed to different geological events such as the formation of rivers. The Old and Young Amazon hypotheses have been proposed regarding the date of the formation of the Amazon basin. Different studies of historical biogeography support the Young A…

Agricultural intensification is a key suspect among putative drivers of recent insect declines, but an explicit link between historical change in agricultural land cover and insect occurrence is lacking. Determining whether agriculture impacts beneficial insects (e.g. pollinators), is crucial to enh…

Insects are the focus of many recent studies suggesting population declines, but even invaluable pollination service providers such as bees lack a modern distributional synthesis. Here, we combine a uniquely comprehensive checklist of bee species distributions and >5,800,000 public bee occurrence re…