Museo Nacional de Historia Natural, Chile

While a clear human presence may be recognised in the Andes by 12 000-11 000 cal BP, most archaeological research has focused on occupation of the Andean highlands. To understand the initial occupation of inland areas of South America, the authors consider regional connections and spatial exploitation strategies of hunter-gatherers highlighted in a recent survey of Andean sites. Focusing on north-central Chile, artefacts and radiocarbon dates from three rock shelters suggest sporadic and brief occupation during the Terminal Pleistocene-Early Holocene. Co-occurrence of marine and montane resources, the authors argue, demonstrates a strategy of high mobility and local adaptation in early Andean occupation , using rock shelters as landmarks to navigate and learn new landscapes.

Acroceridae are active parasitoids of mygalomorph spiders. However, little is known of their interaction numbers and biology in the Neotropics. In this study, we present 15 new records of acrocerid-mygalomorph interactions, adding new biological information about spider fly development. Mygalomorph spiders were captured in the field and maintained in captivity, and the development time of acrocerids was followed from the 4th instar to adulthood. Only seven acrocerid flies were able to complete their development. The acrocerids obtained were Arrhynchus stuardoi, Arrhynchus maculatus, and Archipialea sp. The total recorded development time (from the point where the larva leaves its host to the eclosion of the adult fly) of the spider flies was between 20 and 29 days. The collaboration of citizen scientists could be a useful alternative in the future to fill gaps in the biological and ecological information about these parasitoid flies.

This article discusses the archaeological implications of the discovery of the highland species Hippocamelus antisensis (Cervidae) and Vicugna vicugna (Camelidae) in two coastal contexts in the Atacama Desert (20º S, Chile). H. antisensis is currently distributed throughout the Peruvian Andes, northern Chile, western Bolivia and northwestern Argentina, between 1800 and 5500 m above sea level. V. vicugna is distributed throughout northern Peru and northwestern Argentina, in environments that exceed 3200 m above sea level. The archaeological record of deer antlers on the Atacama coast has previously been documented at the Caleta Huelén-42 site (21º S). In the case of V. vicugna, fibers have been recovered only at the coastal site of Camarones-14 (19º S). A dating of 4180 ± 20 year BP obtained from V. vicugna bone and indirect dating of the antlers suggest an early social exchange between groups from coastal regions and those from the Atacama Desert Mountain range, as well as encourage to the potential record of remains/products of these animals in areas far from their natural habitats.

The South American archaeological record has ample evidence of the socio-cultural dynamism of human populations in the past. This has also been supported through the analysis of ancient genomes, by showing evidence of gene flow across the region. While the extent of these signals is yet to be tested, the growing number of ancient genomes allows for more fine-scaled hypotheses to be evaluated. In this study, we assessed the genetic diversity of individuals associated with the Inka ritual, Qhapaq hucha. As part of this ceremony, one or more individuals were buried with Inka and local-style offerings on mountain summits along the Andes, leaving a very distinctive record. Using paleogenomic tools, we analyzed three individuals: two newly-generated genomes from El Plomo Mountain (Chile) and El Toro Mountain (Argentina), and a previously published genome from Argentina (Aconcagua Mountain). Our results reveal a complex demographic scenario with each of the individuals showing different genetic affinities. Furthermore, while two individuals showed genetic similarities with present-day and ancient populations from the southern region of the Inka empire, the third individual may have undertaken long-distance movement. The genetic diversity we observed between individuals from similar cultural contexts supports the highly diverse strategies the Inka implemented while incorporating new territories. More broadly, this research contributes to our growing understanding of the population dynamics in the Andes by discussing the implications and temporality of population movements in the region.

Resumen Los últimos trabajos de sondeo llevados a cabo en la zona de reservas de la cultura Chinchorro en el Morro de Arica (Desierto de Atacama, costa centro-sur andina), han permitido fechar y analizar estratigráficamente los depósitos domésticos asociados espacialmente a las conocidas áreas de funebria Chinchorro de los sitios arqueológicos Morro 1, Morro 1/6, Morro 1/5 y Colón 10. El rango de fechas ¹⁴ C precerámicas obtenidas en este sondeo (7090-3715 cal aP), en comparación al rango de fechas ¹⁴ C de funebria (6453-3687 cal aP) registradas en estudios anteriores, permite hipotetizar para los espacios domésticos de este sector del Morro de Arica, un probable momento ocupacional previo al desarrollo de la momificación entre la población humana. El análisis crono-estratigráfico llevado a cabo sugiere un proceso de formación de sitios marcado por dos momentos de actividad fúnebre en asociación con la actividad doméstica vecina. Esta última se inicia más tempranamente, y todos los depósitos se encuentran intensamente intervenidos durante momentos alfareros, intermedio tardíos y tiempos recientes.

We present an updated distribution of Akodon reigi , a sigmodontine endemic to Campos in southern South America, and explore its habitat of occurrence and genetic diversity. Our findings reveal new occurrences of A. reigi extending approximately 110 km northwest and 120 km northeast beyond previously known limits. Contrary to previous assumptions of close association with forest formations, recent sightings suggest a degree of habitat plasticity within the species, with specimens found in shrubby/herbaceous phytophysiognomies. Fifty-three individuals sequenced for Cytochrome b (cyt b ; 806 bp) and the first exon of Interphotoreceptor Retinoid Binding Protein (IRBP; 408 bp) showed low variability. Eleven distinct cyt b haplotypes were identified. The largest haplotype richness was observed in a locality in the Sul-Riograndense Shield, a region that could represent a center of the species' genetic diversification. No nucleotide variation was observed for IRBP. No significant indications of population expansion or contraction were detected. The relatively small range, the low genetic diversity, and the current condition of habitat stress due to floods related to global climate change draw attention to the species’ conservation.

The genus Elasmoderus belongs to the family Tristiridae, an orthopteran group that is distributed across the transitional region of South America and represented in the Andean areas of Peru, Argentina, and Chile. The species of Elasmoderus have morphological adaptations that make them especially suited for surviving in extreme arid environments and are an endemic and eremic group of the north-central region of Chile. On the basis of field samplings, direct observations, and a comprehensive literature review, we collected information about the genus Elasmoderus. The objectives of this research were: (i) to provide updated information on the geographical distribution range of the species of the genus Elasmoderus, and (ii) to collect and synthesize the most relevant information on the natural history and ecology of this orthopteran group as a basis for future long-term studies of its populations. Although this genus is underrepresented compared to other orthopteran families, it has developed interesting adaptations to extreme arid environments that remain unstudied to this date. E. lutescens is known to be one of the species with a wider latitudinal distribution, mostly on the coast and longitudinal valley of Atacama. E. minutus has a more restricted distribution, whereas E. wagenknechti is concentrated in coastal and interior environments of the Coquimbo region, an area where it reaches high population densities, thus affecting crops and natural vegetation and polluting water sources. Our findings underscore the importance of conducting comprehensive research on native insect groups that are poorly known but crucial for arid and semiarid ecosystems. These data will serve as a starting point for conducting long-term studies on this orthopteran group to gain a better understanding of the importance and role of these species in the semiarid ecosystems of northern Chile.

We present the results of an interdisciplinary study conducted at the Pedernales-5 site, situated in the Salar de Pedernales basin (26°S; 3356 masl), dated from 10,510−10,749 to 11,201−11,612 cal. BP. Unlike other Late Pleistocene and Holocene sites in the Andean Puna, where vicuñas (Vicugna vicugna) were the primary prey, at Pedernales-5, the zooarcheological assemblage consists almost exclusively of flamingo (Phoenicopteridae) and bird remains. Through the analysis of lithic and bone artifacts, archeobotanical remains, pigment composition, and paleoenvironmental data, we propose that the emphasis on flamingo exploitation cannot be solely explained by alimentary consumption but also served cultural and symbolic purposes related to the acquisition of feathers, hides, and bones. The unique archeological context of Pedernales-5 offers a distinctive perspective on human dynamics in the Andean highlands during the Early Holocene.

Asteraceae is the world’s richest plant family and is found on all continents, in environments ranging from the coast to the highest mountains. The family shows all growth forms and, as in other angiosperm families, species richness is concentrated in tropical regions. South America has the highest diversity of Asteraceae in the world, yet taxonomic and distributional knowledge gaps remain. This study compiles an updated catalog of Asteraceae native to South America, based on national and regional checklists and ongoing large-scale flora projects. The resulting checklist includes a total of 6,940 species and 564 genera native to South America to date, which represent about a quarter of the family’s global diversity. Countries already considered to be megadiverse show the greatest diversity, such as Brazil with 2,095 species, followed by Peru (1,588), Argentina (1,377), and Colombia (1,244), with this diversity mainly focused on the Brazilian Highlands and the Andes. Species endemism also peaks in Brazil, but Sørensen distances reveal the Chilean flora to be eminently different from the rest of the continent. Tribes better represented in the continent are Eupatorieae, Senecioneae and Astereae, also with a remarkably presence of entirely South American subfamilies representing earliest diverging lineages of the Asteraceae, such as Barnadesioideae, Wunderlichioideae, Famatinanthoideae, and Stifftioideae. It is estimated that the discovery and description curves have not yet stabilized, and the number of species is likely to increase by 5 to 10% in the coming years, posing major challenges to continental-scale conservation.

Hanseniella chilensis is the only myriapod of the class Symphyla known from Chile. This garden centipede, or pseudocentipede, was described more than 120 years ago based on morphologically incomplete specimens collected in central Chile, a well-known biodiversity hotspot. In this study, we redescribe this species based on morphologically complete specimens collected near the type locality using scanning electron microscope images. Our study provides the description of diagnostic characters hitherto unknown in this species such as macrochaetae of the tergites and spinnerets of the cerci. We also include a new record from central Chile and discuss the presumed presence of this species in Argentina and Madagascar.

Caviomorph rodents are an exceptional model for studying the effects of ecological factors and size relations on brain evolution. These mammals are not only speciose and ecologically diverse but also present wide body size disparity, especially when considering their fossil relatives. Here, we described the brain anatomy of the largest known rodent, Josephoartigasia monesi, uncovering distinctive features within this species regarding other taxa. Albeit resembling extant pacarana Dinomys branickii, J. monesi stands out due to its longer olfactory tract and well-developed sagittal sinus. Challenging the previous hypothesis that giant rodents possessed comparatively smaller brains, we found that J. monesi and another giant extinct rodent, Neoepiblema acreensis, are within the encephalization range of extant caviomorphs. This was unraveled while developing the a Phylogenetic Encephalization Quotient (PEQ) for Caviomorpha. With PEQ, we were able to trace brain-size predictions more accurately, accounting for species-shared ancestry while adding the extinct taxa phenotypic diversity into the prediction model. According to our results, caviomorphs encephalization patterns are not the product of ecological adaptations, and brain allometry is highly conservative within the clade. We challenge future studies to investigate caviomorphs encephalization within different taxonomic ranks while increasing the sampled taxa diversity, especially of extinct forms, in order to fully comprehend the magnitude of this evolutionary stasis.

This article examines a new dataset of radiocarbon dates that provides insights into the progressive installation of Inca infrastructure in the Copiapo Valley, situated at the southern edge of the Atacama Desert in northern Chile. It shows that the Inca imperial expansion in this region was not a linear process and was likely shaped by local negotiations and conflicts. The findings describe three main stages of Inca expansion. The first is the construction of the North–South Inca Road and the establishment of high-altitude mountain shrines. The next stage consisted of a physical intervention in a local village located in the upper valley, including the construction of administrative buildings and public spaces. The last stage involved indirect intervention in local villages, characterized by the presence of isolated administrative buildings that were potentially used for diplomacy and negotiation. I argue that the Inca imperial expansion, characterized by evolving strategies across regions and time periods, not only demonstrates the state's capacity for learning but also suggests the pivotal role of local actors in positions of power who wielded agency to shape these developments.

Beetle species living in high-latitude forests may be sensitive to variations in habitat conditions and microclimate. We tested that the functional traits and guild structure of canopy-dwelling beetle species of the southernmost subantarctic forests respond to habitat and microclimate. Beetles were collected in 50,400 m radius circular landscapes regularly distributed over the study area, where habitat and microclimate variables were quantified. We assigned species to representative ecological guilds and estimated four components of functional diversity using traits related to feeding ecology, dispersion, size and color patterns. Generalized linear mixed models were used to estimate the additive and interactive effects of habitat and microclimate. The cover of open habitats (peatbogs and meadow) and landscape diversity had a negative effect on functional dispersion and richness, as well as on the abundance of large-sized, small-sized and saproxylic species. The moisture stress index (MSI) negatively affected the abundance of all species, large-sized species and saproxylic species. Winter temperature positively affected predators and interacted with woodpecker’s foraging holes to positively affect small-sized species. A larger density of dead trees positively influenced large-sized species and reduced the negative effect of elevation and MSI on saproxylic species. These findings suggest that human-created habitat heterogeneity engages in negative effects on different guilds of beetles whereas climate conditions are limiting factors. However, unfavorable microclimate conditions are buffered by habitat and microhabitat features. Therefore, the conservation of beetle assemblages in high-latitude forests requires the preservation of habitats and microhabitats providing less stressful climate conditions to beetles.

Two new species of Haplopappus (Asteraceae) from central Chile are described in this article. Haplopappus colliguayensis sp. nov. is restricted to La Chapa hill, Colliguay, Valparaíso Region, and is most similar to H. undulatus but differs from the latter in its stem indumentum, leaf shape and margin, and synflorescence arrangement. Haplopappus teillieri sp. nov . has been recorded from four high-Andean localities in the Choapa, Petorca, Rocín and Aconcagua river basins, and is most similar to H. punctatus but differs from the latter in its leaf length and margin, number of peduncles per twig, width of outer phyllaries, number of ray florets per capitulum, and achene dimensions. Additionally, we propose the reinstatement of H. kingii in agreement with an exhaustive revision of type material and protologues, as well as the study of herbarium specimens. Haplopappus kingii is restricted to mountainous areas in the southern portion of the Atacama Region, and resembles H. parvifolius and H. retinervius but differs from both by its leaf margin and apex, besides additional differences from each. We provide morphological descriptions, field images, distributional maps, conservation assessments, and taxonomic notes for the three species treated, as well as illustrations for the novel taxa.

Diapoma pampeana was recently described to occur in the upper Negro basin in Uruguay and Brazil. An isolated population tentatively identified as D. pampeana from the Pando stream, a perturbed coastal drainage in Uruguay, is studied and compared under the light of morphological and molecular data to test if there is evidence to consider it as a separate species. New geographical records for the species are presented and included in the comparisons. The specimens analyzed were pooled into four groups: Pando, Santa Lucía, Middle Negro and Upper Negro. We analyzed 32 morphological characters using statistical procedures and recovered a COI-based phylogeny of different populations of D. pampeana to test if they may represent different species. Size-corrected PCA revealed that the Pando and Upper Negro groups are greatly diverging in both morphometric and meristic data along PC1 (mainly by the snout to dorsal-fin origin, dorsal to adipose-fin origins, number of longitudinal scales and predorsal scales). This deviating pattern was also obtained in a cluster analysis. The Santa Lucía and Middle Negro groups were found to be intermediate morphotypes. In contrast, molecular analyses revealed that the Pando and Upper Negro specimens resemble genetically and, thus, are placed together in the Neighbor-joining and Bayesian topologies, as part of a monophyletic Diapoma . We proposed that the Pando population, despite its deviating morphology observed, can be classified as D. pampeana . Therefore, this population constitutes a remarkable example of an isolated population that is morphologically divergent but genetically similar to the geographically most distant conspecific population.

Carpobrotus edulis, a highly invasive plant species repeatedly introduced along the Atlantic coast of South America, poses a significant threat to the ecological integrity of coastal dune ecosystems in Uruguay. This study used 15 years of iNaturalist records to assess the magnitude of Carpobrotus invasion, focusing on its distribution, abundance, and reproductive phenology. Through the analysis of georeferenced and dated data, we determined that Carpobrotus has spread extensively, covering a 10-km-wide coastal area and occupying approximately 220 km along the Atlantic coast and the outer Rio de la Plata estuary. Records have increased in the last three years, with a summer prevalence of 52.9%, due to higher activity on the platform. The species exhibited two flowering peaks in spring and autumn, suggesting an extended reproductive period. The widespread presence of this species in both natural and urbanized areas highlights the urgent need for effective management strategies to mitigate its impact on native biodiversity. Utilizing citizen science platforms like iNaturalist has been instrumental in monitoring and documenting processes of invasion. However, further investigations are necessary, particularly in less sampled regions, to fully understand the extent of Carpobrotus invasion. To protect the country’s coastal ecosystems, it is crucial for local authorities to reassess current practices related to non-native species ornamental planting. By addressing the invasion of C. edulis, the ecological integrity of coastal dune ecosystems can be preserved, ensuring the survival of native flora and fauna along Uruguay’s Atlantic coast.

With 76 currently valid species, the bushynose catfish genus Ancistrus is the fourth most species‐rich catfish genus, yet Ancistrus diversity remains underestimated, with many species still undescribed. This is especially true of the Peruvian Andean headwaters of the Amazon, which are rich in unnamed Ancistrus species but have received little recent taxonomic attention. We describe a distinctively striped new Ancistrus species from tributaries of the Palcazú River, in the Pachitea‐Ucayali‐Amazonas drainage basin. The new species differs from all congeners by having black, vermiculated lines covering the head and two to four distinct black, parallel, lateral body stripes from head to caudal fin (vs. body uniformly colored or with dark or light spots or blotches over head and body, or black vermiculate lines on flanks). The new species is the fifth valid species of Ancistrus described from the rich Ucayali River ichthyofauna. It has previously been recognized in the aquarium fish trade as L267.

Today’s Campos Sulinos have witnessed important paleogeographic, paleoclimatic, and paleoenvironmental shifts in the last 300 million years. When this history is evaluated through the perspective of fossil-bearing sedimentary rocks, it can be divided into four major events: Permian deglaciation and evolution to an alluvial plain in Pangean condition; Triassic recovery of a massive extinction and development in alluvial plains in Pangean circumstances; establishment of an aeolian system under desertic conditions during the Jurassic-Cretaceous; and the Pleistocene onset of megafauna and dominance of grassland vegetation responding to glacial and interglacial cycles. Permian biotas range from marine parareptiles, such as mesosaurs, to fully terrestrial fauna, including large herbivores such as provelosaurids, a saber-toothed herbivore, and large carnivores. Terrestrial environments were dominated by a Glossopteris Flora, with large pteridophytes and primitive gymnosperms. Triassic biota vary from near-the-water parareptiles, temnospondyls, and archosauromorphs, right after the most impressive mass extinction on our planet, to the onset of dinosaurs and the evolution of cynodonts. The Triassic also witnessed one of the main vegetation transitions in Earth’s history: environments once dominated by a Glossopteris Flora gradually became occupied by Dicroidium and Coniferous Floras. The Jurassic faunas are mostly represented by dinosaur footprints from a desert-dominated environment prior to the South America/Africa breakup. Late Pleistocene biota includes large-bodied mammals and reptiles, representatives of the so-called Pleistocene Megafauna. In addition, extant taxa are also present in the fossil record. The Late Pleistocene paleobotanic fossil record demonstrates widespread grasslands that were only slowly subject to the expansion of forests.

The Pacific coast of the Southern Andes has a long occupational history that shows regional diversification by the Middle and Late Holocene. The coast of north-central Chile had a significant hunter-gatherer occupation between cal 6000 and 2000 BP, which differs from those observed in neighboring areas because of their envionmental and historic characteristics. Studies of funerary contexts reveal that these groups underwent a demographic expansion and experienced social conflict during this period. But an emphasis on the significance of funerary contexts in the period cal 6000-2000 BP has limited our knowledge of these groups’ environmental strategies and use of coastal resources. This research examines evidence recovered from residential and funerary contexts from the Punta Teatinos site (Coquimbo Bay, north central coast of Chile, 29°S) to assess the strategies of environmental use. The study of this evidence—including stratigraphy; radiocarbon dating; lithic, malacological, and zooarchaeological material; microfossils; dental calculi, stable isotopes; and rock art—indicates an exploitation of coastal resources, to which others of terrestrial origin were added. Although no temporal changes in the exploitation of coastal resources were identified, the evidence also indicates changes in the constitution of historical landscapes and extra-regional social networks.