Renan da Silva Olivier

Understanding the distribution of rare species is important for conservation prioritisation. Traditionally, museums and other research institutions have served as depositories for specimens and biodiversity information. However, estimating abundance from these sources is challenging due to spatiotemporally biased collection methods. For instance, large‐bodied reptiles that are found near research institutions or in popular, easily accessible sites tend to be overrepresented in collections compared to smaller species found in remote areas. Recently, a substantial number of observations have been amassed through citizen (or community) science initiatives, which are invaluable for monitoring purposes. Given the unstructured nature of this sampling, these datasets are often affected by biases, such as taxonomic, spatial and temporal preferences. Therefore, analysing data from these two sources can lead to different abundance estimates. This study compiled data on Brazilian reptile species from the Global Information Biodiversity Facility (GBIF). It employed a community‐ecology approach to analyse data from research institutions and citizen science initiatives, separately and collectively, to assess taxonomic and spatial species coverage and predict species rarity. Using a 1‐degree hexagonal grid, we analysed the spatial distribution of reptile communities and calculated rarity indices for 754 reptile species. Our findings reveal that 87 species were exclusively recorded in the citizen science subset, while 212 were recorded only by research institutions. The number of observations per species in the citizen science data followed a Gambin distribution, which aligns with the expected pattern of abundance in natural communities, unlike the data from research institutions. This suggests that citizen science data may be a more accurate source for estimating species abundance and rarity. The discrepancies in rarity classifications between the datasets were likely due to differences in sample size and potentially other sampling parameters. Nevertheless, combining data collected by both research institutions and citizen science initiatives can help to fill knowledge gaps in reptile species occurrence, thus enhancing the foundation for conservation efforts on a national scale.

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.

Global climate change will likely exacerbate crop losses from insect pests, reducing agricultural production and threatening food security. To predict where crop losses will occur, scientists have mainly used correlative models of species’ distributions, but such models are unreliable when extrapolated to future environments. To minimize extrapolation, we developed mechanistic and hybrid models that explicitly capture range‐limiting processes, and we explored how incorporating mechanisms altered the projected impacts of climate change for an agricultural pest, the South American locust (Schistocerca cancellata). Because locusts are generalist herbivores surrounded by food, their population growth may be limited by thermal effects on digestion more than food availability. To incorporate this mechanism into a distribution model, we measured thermal effects on the consumption and defecation of field‐captured locusts and used these data to model energy gain in current and future climates. We then created hybrid models by using outputs of the mechanistic model as predictor variables in correlative models, estimating the potential distribution of gregarious outbreaking locusts based on multiple predictor sets, modeling algorithms, and climate scenarios. Based on the mechanistic model, locusts can assimilate relatively high amounts of energy throughout temperate and tropical South America; however, correlative and hybrid modeling revealed that most tropical areas are unsuitable for locusts. When estimating current distributions, the top‐ranked model was always the one fit with mechanistic predictors (i.e., the hybrid model). When projected to future climates, top‐ranked hybrid models projected range expansions that were 23‐30 percentage points smaller than those projected by correlative models. Therefore, combining the correlative and mechanistic approaches bracketed the potential outcomes of climate change and enhanced confidence where model projections agreed. Because all models projected a poleward range expansion under climate change, agriculturists should consider enhanced monitoring and management of locusts near the southern margin of the range.