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This paper explores illegal coca crop expansion in indigenous Amazonian communities in Peru. The ethnographic study sheds light on the historical development of these areas as frontier spaces, where the growth of illicit crops intertwines with socio-ecological transformations and gives rise to conflicts over new forms of land control, opportunities for capital accumulation, and political power dynamics. The paper argues that this expansion is shaped by dual processes: from 'below,' involving small-scale migrant farmers from the Andes, and from 'above,' primarily driven by state-led agrarian interventions. Consequently, communities experience significant tensions, as they adapt to the forces of market expansion to secure their livelihoods, while simultaneously facing risks of violence and insecurity. [ABSTRACT FROM AUTHOR]

This paper employs the concepts of heritage-making, communal identity formation, and landscape production to analyse the spaces that contribute to local, provincial, and national identities. Specifically, we examine how these spaces, now valued for their natural and historical significance, shape contemporary collective identity. Our study is located in the Andes mountain range, in an area called Manzano Histórico, in central- western Argentina, which is part of a larger nature reserve created to protect the headwaters of the basin and mountain areas from large-scale economic projects. This paper utilises a qualitative methodology that combines archaeological and historical studies with ethnographic techniques and a survey to describe and analyse the millennial occupation of the region. This continuous occupation has been shaped by multiple ways of inhabiting the world, some dominant and others marginalised or made invisible, resulting in ongoing present-day tensions. The heritage landscape proposed is a partial result of these tensions, a textured, fractured, and patched product of diverse, historically enabled practices. By analysing these spaces, we aim to acknowledge the various ways of being in the world that intersect within them, as well as the identity formations of alterity that hierarchise or invisibilise these practices. [ABSTRACT FROM AUTHOR]

This paper seeks to advance our theoretical understanding of diversifying and homogenizing processes in human societies by exploring the sources of and threats to ethnolinguistic or cultural diversity. Invoking concepts such as ethnogenesis, schismogenesis, and structural transformations, it discusses the parallels as well as the divergences between biological and cultural theory. Models in historical linguistics risk importing unwarranted assumptions about diversification from biological models of speciation. A more pertinent theorization of ethnolinguistic diversity might build on anthropological perspectives such as those of Fredrik Barth, Gregory Bateson, and Claude Lévi-Strauss, all of whom recognized that such diversity reflects interaction rather than isolation. The empirical test of these considerations is the ethnography and history of language use among Indigenous peoples in Amazonia and the Andes. The conclusion is that premodern expansions of language families, in tolerating local cultural autonomy, multilingualism, and diglossia, did not threaten ethnolinguistic identities as has modern globalization. [ABSTRACT FROM AUTHOR]

In this paper we explore what campesino [peasant] livelihoods in the rural Andean mountains of Colombia offer to understandings of more-than-human co-existence and care. For, while new conservation paradigms promise to transform economic and social horizons, being "paramuno" [resident of the "paramo," or high moorlands] in the small community of Monquentiva is already characterized by becoming-with-other-beings-and-practices; a disposition toward incorporation of elements that are at-hand, and an ethics of care toward other beings in the landscape. We draw on ethnographic data to present this case study, emphasizing the forms of social organization and persistence that have enabled the emergence of economically and ecologically sustainable livelihoods. We explore these processes in terms of what we call world-making practices, showing how relationships with Indigeneity and collectivity are being renegotiated, and arguing for modes of conservation that engage with existing forms of peasant innovation. [ABSTRACT FROM AUTHOR]

Plot-based monitoring has yielded much information on the taxonomic diversity and carbon (C) storage in tropical lowland forests of the Amazon basin. This has resulted in an improved understanding of the relationship between lowland forest biomass dynamics and global change drivers, such as climate change and atmospheric CO2 concentration. Much less attention has been paid to the mountain ecosystems of South America that comprise montane forests and alpine vegetation (páramo, puna, high Andean grasslands, wetlands, and alpine heath). This vegetation complex provides a variety of ecosystem services and forms a natural laboratory along various physiographic, geological and evolutionary history/biogeography, and land use history gradients. Here, we review existing empirical understanding and model-based approaches to quantify the contribution of mountain ecosystems to ecosystem service provision in the rapidly changing socioecological setting of the South American mountains. The objective of this paper is to outline a broad road map for the implementation of mountain vegetation into dynamic global vegetation models (DGVM) for use in Earth System Models (ESM), based on our current understanding of their structure and function and of their responsiveness to global change drivers. We also identify treeline processes, critical in mountain ecosystems, as key missing elements in DGVMs/ESMs, and thus explore in addition a treeline model. Stocktaking of the availability of empirical data was undertaken from eight research sites along the Andes and in south-eastern Brazil. Out of eight sites, two (one each in Venezuela and Brazil) had some climate, ecological and ecophysiological data potentially suitable to parametrise a DGVM. Tree biomass data were available for six sites. A preliminary assessment of the Joint UK Land Environment Simulator (JULES) DGVM was made to identify gaps in available data and their impacts on model parametrisation and calibration. Additionally, the potential climate-determined elevation of the treeline was modelled to check the DGVM for its ability to identify the transition between the montane forest and alpine vegetation. Outcomes of the evaluation of the JULES land surface model identified the following key processes in montane forests: temperature-related decrease in net primary production, respiration, and allocation to above-ground biomass and increase in soil C stocks with elevation. There was a variable agreement between simulated biomass and those derived from field measurements via allometric equations. We identified major gaps between data availability and the needs for process-based modelling of South American mountain vegetation and its dynamics in DGVMs. To bridge this gap, we propose a transdisciplinary network, composed of members of the theoretical/modelling and empirical scientific communities, to study the natural dynamics of mountain ecosystems and their responses to global change drivers locally, regionally and at the continental scale, within a social-ecological system framework. The work presented here forms the basis for the design of data collection from field measurements and instrumental monitoring stations to parametrise and verify DGVMs. The network is designed to collaborate with and complement existing long-term research initiatives in the region and will adopt existing standard field protocols. Complementary protocols will ensure compatibility between field data collection and data needed for process-based and empirical models. [ABSTRACT FROM AUTHOR]

The paper, 'A relational turn for sustainability science? Relational thinking, leverage points and transformations' presents a compelling summary of the incipient relational turn in sustainability science. That piece and the reply and response that follow put forth important arguments about what relational thinking is and how it can infuse sustainability science research. We are grateful for this conversation, but also recognize that crucial intellectual contributions from the Global South require further treatment. In response to West et al'.s invitation to conversation, we offer a summary of a diverse body of scholarship and practice that informs sustainability science in subtle but clear ways: Latin American contributions. We first summarize a set of Latin American theoretical contributions to relational thinking relevant to sustainability science. We then offer examples of how relational thinking infuses everyday life in many Latin American contexts. We close with reflections on the importance of Latin American thinking for sustainability science and transformations toward sustainability. [ABSTRACT FROM AUTHOR]

This paper explores institutional changes in two water users' associations (WUAs) in the Venezuelan Andes. The methodology is based on ethnographic work. The results show that both WUAs have modified the rule systems in irrigation management to respond to economic, institutional and environmental changes. They have implemented a better organization of water sharing, adopted more efficient irrigation technologies, restored infrastructure and preserved high-altitude wetlands. The comparative approach adopted allowed us to show not only the similar factors that promoted institutional change, such as social capital, but also the differences related to the characteristics of the resource. [ABSTRACT FROM AUTHOR]

Innovation has been central to development. Yet most assumptions around innovation stem from values derived by capitalist economies such as growth, individualism, and competition which prove to only widen inequalities and promote unsustainable environmental models of extraction and consumption. This paper explores what values and assumptions would underlie innovation in development if based on an alternative ontological and epistemological stance linked to the Andean cosmovision of Buen Vivir. We focus on the case of an Indigenous-led initiative in the Andes of Peru to highlight the underpinnings of its innovation processes. In doing so, we aim to contribute to both development studies literature and innovation studies by exposing the limitations to the accepted Western approach to innovation and exploring what decolonising innovation in development would look like. [ABSTRACT FROM AUTHOR]

In 2013, the Collaborative Crop Research Program (McKnight Foundation), initiated support for farmer research networks (FRNs). FRNs were envisaged as a general approach to networked participatory research aimed at supporting the agroecological intensification (AEI) of smallholder farming in ten countries in Africa and the Andes region in South America. The 30 FRNs ranged in size from 15 to more than 2,000 farmers. Rather than imposing a rigid FRN model, the programme used principles to guide action and reflection. The principles concerned ways of working with farmers, conducting research, and networking. This approach made it possible to reflect on how principles were interpreted, implemented, and used to guide learning in different contexts. This paper reports on insights gained from facilitated learning from 2013–2019 and focuses on subsets of diverse FRNs. Of the 30 FRNs supported, four were analyzed at some depth, reports and interviews were analyzed for 16, and a survey was conducted for 21. Relying on principles rather than an operational model has allowed for their progressive application, as participatory processes, farmer engagement, organizational capital, trust, and networks are built. Any reduced clarity and coherence seem outweighed by greater adaptability to context and resulting creativity. [ABSTRACT FROM AUTHOR]

In the Neotropics, Panopinae spider flies are the most diverse within Acroceridae, specializing as endoparasites of mygalomorph spiders. Camposella insignata Cole, 1919 is one of the most enigmatic flies within this subfamily, given its conspicuously enlarged antennal flagella and apparent rarity, with only two specimens known to this day. This paper describes recently collected C. insignata specimens from the Ecuadorian Andes and provides pictures and measurements. We also discuss the possible function of the enlarged antennal flagella and give recommendations on future collection efforts to increase knowledge about this enigmatic genus. [ABSTRACT FROM AUTHOR]

In this paper we review the growing evidence of anthropogenic landscapespresent in the semi-deciduous neotropical forest biomes of eastern NW Argentina,which have remained relatively neglected in favour of arid to semi-arid western Andean regions. The evidence gathered in de El Alto-Ancasti provides animportant case study where multidisciplinary methodologies have beenapplied to sites that document the emergence and variability in food productionstrategies across the eastern Andean forests and grasslands of NWArgentina. We discuss evidence offarming structures from archaeological surveys, plant management from phy-tolith analysis, and the tempo and nature of settlement from archaeological excavations undertaken at a variety of sites in the El Alto Ancasti mountainrange. We suggest that the communities that inhabited this region during thefirst millennium AD (ca. 1500–1000 BP) established a strategy of 'overlappingpatchworks' of food production that were able to contend with considerableseasonal variability. We argue that, through the use of cross-channelling, low river areas, erosion control techniques and the establishment of mesothermal crops,including maize, legumes, and tubers, throughout the region, these societies adopted flexible strategies to adapt to life in a region prone to climatic change [ABSTRACT FROM AUTHOR]

Top-down processes of regional integration among the Andean countries of South America are occurring alongside bottom-up processes of Indigenous regionalism in Bolivia and Ecuador that weave together Indigenous peoples' territories across local administrative units and even national borders. In light of this dynamic, the study asks: What explains the new Indigenous regionalism in the Andes? And, what are its implications for formal processes of regional integration? The study examines the cases of the Coordinator of Indigenous Organizations of the Amazon River Basin (COICA) and the National Council of Ayllus and Markas of Qullasuyo (CONAMAQ) as examples of Indigenous regionalism in relation to the institutional innovations of the Andean Community of Nations (CAN) to incorporate Indigenous organizations into its structure and agenda. The article argues that the intersections of regional integration, the enactment of the plurinational state, and Indigenous autonomies have provided the necessary institutional space for expressions of Indigenous regionalism to flourish. [ABSTRACT FROM AUTHOR]

Colonial control is studied through a narrative sound designed to entomb a black woman's voice under noise. Interpreting Charles Marie de La Condamine's 1746 letter, recounting the murder of a colleague during his scientific travels through Cuenca, involves mapping the effort to quell the scandalous scream of an enslaved woman who spoke up against the traveller and went unpunished. The text is read for the concatenation of sounds that follow her scream and the way these accrue into white, order-restoring noise at the hands of the author. However, simultaneously tracking how this defiant sound travels and is inscribed through layers of noise underscores the limits of such attempts to erase a racialised voice. Examining this tangential episode in an Andean town within La Condamine's larger Geodesic Mission (1735–45) introduces narrative silencing to the study of noise-making, wherein race thwarts the act of writing to regulate sounds during colonial encounters. [ABSTRACT FROM AUTHOR]

Imaginaries arerepresentational assemblages of the past, ways to understand and(re)create history and projections of the self and others that ground ever-changing identities. They are embedded in the cultural meaning-making systems of each society. However, researchers and practitioners within the heritage field have not directly analysed heritage as a product-producer of imaginaries or conceived heritage itself as an imaginary. This conceptual article proposes imaginaries as a useful analytical lens to critically study heritage. Imaginariesenable us to uncover how people assume and signify heritage from various positions and experiences. Furthermore, this article aims to shed light on how alternative imaginaries grounded in non-western ontologies enable us to rethink heritage meaning and practice in the encounters and conflicts between different systems of meaning in daily life. More concretely, we identify three significant contributions of using imaginaries as a lens for the study of heritage. To illustrate our theoretical propositions, we incorporate empirical examples from ethnographic fieldwork conducted in the Ecuadorian Andes. [ABSTRACT FROM AUTHOR]

Intensification of agricultural land use in traditional Andean production landscapes has led to changes in the provision of nature's contributions to people (NCP) that can threaten people's wellbeing. Understanding local stakeholders' valuation of these NCP is crucial for improving land use decisions. We implemented a spatially explicit and participatory NCP valuation method, using semi-structured interviews and participatory mapping, followed by a spatial multi-criteria decision analysis, to identify priority areas for NCP provision in a highly intensified production landscape in the Colombian Andes. We considered multiple value types, ecological, economical and sociocultural, and the points of view of different actors, orienting this towards decision-making on land use. Our results show that local actors can identify and value a wide range of NCP. However, there are also significant differences between actors. Environmentalists attached special importance to regulating NCP, while agricultural laborers focused more on agriculture-related material NCP. As we expected, tourism entrepreneurs especially valued non-material NCP related to their business experiences. Small-scale farmers tended to put more importance on regulating and non-material NCP than big farmers did. Although there was a consensus between actors as to the importance of natural ecosystems for NCP provision, agricultural actors tended to attach more importance to material NCP in areas deemed important for regulating and non-material NCP by other actors. Our main results confirm the importance of involving different stakeholders in spatial NCP valuation exercises, recognizing their different points of view to help identify possible trade-offs and synergies related to land use. [ABSTRACT FROM AUTHOR]

As an alternative to the current technologies, we explored the feasibility of using low cost and massive use of digital cameras as photometric sensors to retrieve the atmospheric total optical depth (τ) in the urban area of a city in the Colombian Andes. This study proposes a simple way to estimate τ from digital processing of images of the Sun based on the Beer-Bouguer-Lambert law Langley's linear fitting for the colour levels in channels red, green, and blue registered by the pixels of cameras' sensors. From February to March 2022, the τ values retrieved from the images were correlated to the retrieved values from a solar spectral radiometer (SSR). We found that τ is sensible to the featured changes in the local atmosphere and to the cameras' exposure parameters setup. Under conditions of partly clear sky, around 80% (r > 0.8) of the τ values from cameras showed a linear correspondence to those retrieved from SSR system. Its spectral dependency (τ _red < τ _green < τ _blue) is in accordance with the physical phenomena in light-atmosphere interaction. The results suggest that the methodology applied can be used for monitoring the atmosphere at any geographical location in the world. [ABSTRACT FROM AUTHOR]

Archaeology has long faced fundamental issues of sampling and scalar representation. Traditionally, the local-to-regional-scale views of settlement patterns are produced through systematic pedestrian surveys. Recently, systematic manual survey of satellite and aerial imagery has enabled continuous distributional views of archaeological phenomena at interregional scales. However, such 'brute force' manual imagery survey methods are both time- and labour-intensive, as well as prone to inter-observer differences in sensitivity and specificity. The development of self-supervised learning methods (e.g. contrastive learning) offers a scalable learning scheme for locating archaeological features using unlabelled satellite and historical aerial images. However, archaeological features are generally only visible in a very small proportion relative to the landscape, while the modern contrastive-supervised learning approach typically yields an inferior performance on highly imbalanced datasets. In this work, we propose a framework to address this long-tail problem. As opposed to the existing contrastive learning approaches that typically treat the labelled and unlabelled data separately, our proposed method reforms the learning paradigm under a semi-supervised setting in order to fully utilize the precious annotated data (<7% in our setting). Specifically, the highly unbalanced nature of the data is employed as the prior knowledge in order to form pseudo negative pairs by ranking the similarities between unannotated image patches and annotated anchor images. In this study, we used 95,358 unlabelled images and 5,830 labelled images in order to solve the issues associated with detecting ancient buildings from a long-tailed satellite image dataset. From the results, our semi-supervised contrastive learning model achieved a promising testing balanced accuracy of 79.0%, which is a 3.8% improvement as compared to other state-of-the-art approaches. [ABSTRACT FROM AUTHOR]

The use of natural resources for food production and the identification of viable solutions to problems related to agricultural sustainability are topics of current debate. Our proposed objectives were to: i) determine the agronomic characteristics of strawberry crops in open-field and aeroponic greenhouse production systems, ii) assess the sustainability of production systems concerning social, environmental, economic, and governance dimensions, and iii) identify the variability of sustainability scores between production systems. Surveys were conducted on small Mestizo strawberry producers with open-field production systems and aeroponic production researchers in the Ecuadorian Andes. The SAFA-FAO methodology was applied, considering 111 indicators, 56 subtopics, and 20 topics, distributed among the four dimensions. A principal component analysis was performed using the Infostat programme. The sustainability score (0–5) of the aeroponic system was 1.09 times higher than that of the traditional system. The dimensions of economic resilience (2.23) and good governance (2.29) obtained low scores in the open-field system, and in the aeroponic production system the dimensions with high scores were environmental integrity (4.05) and social welfare (4.46). The identified sustainability dynamics contribute to a better multidimensional understanding for decision-makers and are a contribution toward meeting the goals of the UN's 2030 Agenda. [ABSTRACT FROM AUTHOR]

The movements and habitat use of three species of Sigmodontine rodents (Akodon mollis, Phyllotis haggard and Thomasomys paramorum) from the high Andes of Ecuador were evaluated using the spool-and-line technique in four transects. The floristic composition was analyzed at sampling sites to explain how these three species of Sigmodontine rodents use the vegetation as a habitat. Rodents were captured using live Sherman traps and equipped with a spool-and-line device. Each thread trail was traced, and their nests, feeders and shelters were recorded using GPS receivers. Also, the construction materials, nest morphology and shelters used during foraging, and the food resources were described. These three rodent species overlap in their distribution, but they present certain preferences for different habitats such as grasslands, open areas with cushions and shrubs, respectively. This study is an approach to the natural history of these Sigmodontine rodents in high mountain elevations. [ABSTRACT FROM AUTHOR]

Copyright of Neotropical Biodiversity is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

High Andean ponds and reservoirs are among the least-studied environments. We evaluated the composition of littoral macrobenthos and how it is affected by the physicochemical conditions of the water in El Pañe reservoir (Peru), located at 4,550 m.a.s.l. Samples were taken between November 2017 and October 2018 from three zones in the reservoir: low (downstream), middle and high (upstream); two of these zones with fish farms (low and middle) and one zone without fish farms (high). The following physicochemical parameters of the water were measured: dissolved oxygen, conductivity, pH and temperature. The macrobenthic community was analysed through diversity indices such as Shannon-Wiener (H'), Simpson's dominance index (D), Pielou's evenness (J'), true diversity (D1), and richness (S). The influence of the physicochemical variables on the macrobenthos was estimated by canonical correspondence analysis (CCA) and non-metric multidimensional scaling (NMDS). Dissolved oxygen was found to have lower values (<0.5 mg/l) than specified in the Environmental Quality Standards (EQS). Macroinvertebrate richness for the whole reservoir was 17 families, and the family with highest relative abundance was Chironomidae (42.24% in the low zone, 51% in the middle zone and 40.43% in the high zone). The indices showed greater species richness in the high zone, where there are no fish farms. Dissolved oxygen and conductivity were the main factors determining macrobenthos distribution and composition. [ABSTRACT FROM AUTHOR]

The Devonian Terra Australis accretionary orogen along the proto-Andes is characterized south of 33°S by the eastward accretion of the Chilenia and Chaitenia terranes. From the middle Silurian to the early Carboniferous the evolution north of 33°S, in the southern central Andes, is enigmatic, and herein called the Silurian-Devonian lull. This lull is notable for the absence of magmatism, metamorphism and deformation while mature siliciclastic detritus accumulated in marginal basins governed by depositional and not by tectonic controls. Detrital zircon age spectra uniformly display a marked scarcity of Silurian and Devonian ages. No evidence of a Devonian active margin system has been put forward so far. Newly discovered volcanic arc lavas in the Devonian-early Carboniferous Compléjo Epimetamórfico Chañaral (CEMC) of northern Chile give evidence of Devonian to early Carboniferous intermediate arc magmatism in this area for the first time. The CEMC also includes mafic volcanic rocks as syndepositional intercalations and as tectonic accretions. They predominantly have E-MORB and OIB characteristics and very likely formed at an extensional volcanic rifted margin environment. The veiled presence of scarce arc magmatism during the Silurian-Devonian lull might be taken as evidence of flat-slab subduction. However, present-day flat-slab regimes produce strongly telescoped mountain belts with high topography and relief. The absence of any deformation during the lull attests against this interpretation. Assuming an extension of Chilenia into northern Chile is unlikely because of different stratigraphies and the absence of ophiolitic sutures. The Silurian-Devonian lull may be explained as a magmatic lull between the flare-ups of the Famatinian and Gondwanide orogenies (Cambrian-Ordovician and Carboniferous-Triassic, respectively) the latter of which is attributed to rapid trenchward migration of the volcanic axis. Magmatic lulls are characterized by less than 25% of magma production relative to flare-ups and occur at times of slow landward migration of an arc system. [ABSTRACT FROM AUTHOR]

Copyright of Tapuya: Latin American Science, Technology & Society is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Phenotypically similar species – often called cryptic species – represent a challenge for taxonomy and conservation biology because they are usually undetectable to scientists. To unravel these cryptic taxa, studies now employ data from different sources under an integrative approach. We present an assessment of the cryptic diversity of the Lophostoma brasiliense species complex (Chiroptera: Phyllostomidae) based on multiple lines of evidence (molecular, morphological, morphometric, and geographic data) and using molecular (ABGD, ASAP, GMYC, and bPTP) and phenotypic (distance-based approaches and Normal Mixture Model Analyses) species delimitation methods. Our analyses recognized two distinct lineages with clear allopatric distributions. One lineage corresponds to Lophostoma brasiliense with a cis-Andean distribution and the other to the formerly species Lophostoma nicaraguae with a trans-Andean distribution. The two lineages probably diverged from a vicariant speciation driven by the uplift of the Andes less than six million years ago. Our work also shows that the wide range of environmental conditions during the recent history of South America may have promoted restrictions to gene flow among the populations of Lophostoma brasiliense. Finally, we raised L. nicaraguae to species level clarifying the species limit and morphological characteristics of lineages, and we provide an emended diagnosis and comparisons between the two taxa. We highlight the need for multiple lines of evidence to solve the remaining taxonomic problems among the remaining species complexes in Lophostoma. [ABSTRACT FROM AUTHOR]

The Trichocentrum cepula complex comprises three species, T. caatingaense, T. cepula and T. sprucei, endemic to tropical forests east of the Andes in South America. The delimitation of these species has been diversely interpreted due to the extensive morphological variation in the complex. We applied an integrative approach to achieve a better understanding of these biological units, using geometric morphometrics, cytogenetic analysis (chromosome counts and CMA/DAPI banding) and molecular phylogenetics (ITS and rpl32-trnL). An initial morphometric analysis using the pre-identified specimens into three taxa suggested that T. sprucei is distinct from the other two, which show some overlap. A subsequent analysis of the labellum, including only T. caatingaense and T. cepula organized in six pseudo-populations, suggested the existence of four morphological groups. All analysed specimens presented 2n = 36 chromosomes, CMA+/DAPI− terminal bands and CMA−/DAPI+ pericentromeric bands, which varied in number across species, localities or even individuals from the same locality. The notable variation in DAPI+ pericentromeric bands may be related to transposable elements that could also be a factor influencing the wide morphological variation in the flowers. In the phylogenetic analysis, the specimens belonging to T. caatingaense formed a strongly supported clade sister to the rest, whereas the specimens belonging to T. cepula and T. sprucei emerged together, with their relationships tending to be determined by geographic proximity. The evidence we generated suggests that treating the Brazilian populations of this species complex under a single name, T. cepula, provides more taxonomic stability and utility, thus the necessary taxonomic changes are implemented. [ABSTRACT FROM AUTHOR]

We characterized the crustal thickness variations and magmatic saturation temperatures of the Early Jurassic to Early Cretaceous (194–130 Ma) plutonic and volcanic rocks of the Northern Andes of Colombia and Ecuador, combining trace elements signatures and zircon and apatite saturation temperatures. Also, we analysed the implications of the emplacement conditions during the last stage of the magmatism using Al-in-hornblende thermobarometry. Moderate rare earth elements (REE) slopes and depleted heavy REE patterns show that the primary residual magma source was amphibole, but plagioclase and pyroxene were also significant residual phases indicating that the magma source was formed in a crust that varied in thickness from 35 to 50 km. According to the La/Yb and Sr/Y crustal quantifications and the REE ratios, two phases in the arc evolution are characterized by a thick crust. The first is in Santa Marta Massif, Upper Magdalena Valley and Garzón Massif (190–180 Ma), which could be associated with shortening or basaltic underplating due to magmatic events. The second one recorded in the Ibagué Batholith (160–154 Ma) is related to the crustal thickening on an oblique subduction setting. During the latter period, the magmatic volumes progressively decreased, as is recorded by saturation temperatures increase. Finally, a thin crust emplaced the last stage of the arc magmatism during the Late Jurassic to Early Cretaceous (154–130 Ma). [ABSTRACT FROM AUTHOR]

Two new species of oribatid mites of the family Scheloribatidae – Urubambates jakobisp. nov. and Pachygena annaesp. nov. – are described, based on adults collected from upper soil and leaf litter in primary mountain forests in the Andes, Central Peru. Pachygena makarovae is supposedly a member of the genus Perscheloribates. [ABSTRACT FROM AUTHOR]

The southern boundary of the high level, discordant, Devonian Strathbogie batholith in central Victoria includes two near-linear sections that strike east–west, and one north–south. Field mapping has delineated the 100 km southern boundary with 2200 waypoints taken where granite and hornfels are within 10 m of one another. There is 790 m of topographic relief along the southern boundary and, where the mapping is overlain on contours, there are intervals that reflect a steep-dipping contact and others that reflect near-horizontal contacts. Of the latter, some reflect the granite roof and others the floor. Complementary evidence from mineralogic and textural data indicates a strong correlation between the interpreted roof of the granite and the abundance of tourmaline, aplite and pegmatite. When combined, the roof and floor intervals indicate a batholith thickness up to 350 m; nowhere along the southern boundary can a thickness of 1 km be demonstrated. Along the southern boundary, at least, the batholith shape is a thin, tabular and extensive composite granite sheet analogous to a pizza rather than a pipe. The roof of the granite is nearly horizontal in both east–west and north–south sections, and the plateaux today are close to the batholith roof. On regional and local scales, granite emplacement was determined by pre-existing anisotropies, such as master joint sets, across which the propagation of magma-filled fractures (granite sheets) was arrested. The emplacement records a fine balance between magma pressure, and the interplay of lower confining (overburden) pressures and pre-existing anisotropies that also facilitated roof uplift. The opportunistic magmas used the slightest variations of those parameters. This interpretation of the Strathbogie batholith matches examples in the Himalaya and Chilean Andes but differs markedly from the portrayal of very large batholiths beneath Cu–Au porphyry systems. The boundary of the Strathbogie batholith can be mapped in moderately outcropping terrain to an accuracy of 10 m or better. Steep intervals of the boundary are interspersed with near-horizontal intervals that delineate the granite floor and roof along the 100 km of the southern boundary. The batholith, at least near its southern boundary, comprises near-horizontal sheets of <500 m aggregate thickness. The boundary determined by geophysics is adequate for regional studies but has been misleading in three-dimensional interpretations. [ABSTRACT FROM AUTHOR]

A new species of the genus Diachea (order Physarales, Myxomycetes, Amoebozoa) is described from Peru. Relevant details on spore germination, as well as morphological and phylogenetic data, are provided. At first glance, the new species shares some morphological similarities with both D. leucopodia, type of the genus, and D. koazei, but it strikingly differs from all other species of its genus by combining a short dark stalk, with a reticulate columella, and clustered spores. Moreover, it seems to be the only species of Diachea exclusively associated with Polylepis tropical forests at elevations above 3500 m. Apart from a comprehensive morphological study of 31 specimens, we here provide phylogenetic evidence to confirm the inclusion of this species in the genus Diachea. Specifically, our phylogenetic analyses of the nuclear 18S rDNA (18S), mitochondrial 17S rDNA (17S), and elongation factor-1 alpha (EF-1α) genes show that the new species is related to D. leucopodia and D. bulbillosa. The remarkably different morphological characters distinguishing the new Diachea from all other species of its genus, along with its particular ecological preferences and geographic distribution, indicate that it is a distinct entity deserving recognition as an independent species. [ABSTRACT FROM AUTHOR]

The family Cynodontidae is composed of freshwater fishes inhabiting drainages east of the Andes in South America. Its fossil record is mostly represented by isolated teeth that are difficult to identify. Here we describe fossil cranial remains of the extant species Hydrolycus scomberoides as well as isolated teeth that were identified as Hydrolycus and cf. Rhaphiodon in sediments of the late Pliocene Ware Formation in the Guajira Peninsula, west of the Andes. Novel, phylogenetically informative characters were found including the number of symphysial teeth, the plane of insertion of the leading teeth onto the dentary, the presence of accessory posterior dentigerous patches, and depressions and outline of the dentary. We performed a phylogenetic analysis combining morphological and molecular characters including both extant and extinct specimens, producing a well-resolved topology that recovers a novel sister-group relationship between the genera Hydrolycus and Cynodon, while the genus Rhaphiodon falls to the base of this clade. This contradicts earlier studies recovering Hydrolycus and Rhaphiodon as sister taxa. The phylogenetic position of Hydrolycus wallacei was found to be unstable. The occurrence of H. scomberoides in the late Pliocene of Guajira is a puzzle that could be explained by different mechanisms, including a persistent drainage connection across the Andes during the late Pliocene, and/or the result of severe drying and subsequent extinction. [ABSTRACT FROM AUTHOR]

Little is known about distribution patterns of micrometazoan organisms at different spatial scales and the mechanisms driving these patterns across different environments. Here we explore the fine-scale structure of tardigrades in a high-elevation Polylepis forest in northern Ecuador. To investigate spatial patterns of tardigrade abundance, we collected samples from different bryophyte taxa (hosts) on the woodland floor. We identified some tardigrades to species, but most taxa were considered at the level of morphological operational taxonomic units. Tardigrade assemblages differed in composition between host taxa, with some tardigrade taxa associated more with certain hosts, which might relate to host architecture or chemistry. Tardigrade occupancy, richness and abundance varied considerably between samples, and we estimate that more than 50 samples are required to estimate tardigrade taxon richness in this forest habitat. Physical distance between samples was not related to similarity of composition, and it seems that fine-scale differences in environmental conditions (including the distribution of host bryophytes) is much more important in determining tardigrade composition. We conclude that standardised, comprehensive sampling of terrestrial tardigrades at fine scales is necessary before making broader comparisons at coarser geographical scales. Such sampling should account for the diversity of potential hosts, with sufficient replication to capture tardigrade diversity. [ABSTRACT FROM AUTHOR]

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Habitat fragmentation is a severe problem that negatively affects forests around the world. This phenomenon has consequences at a genetic level in populations such as genetic diversity and gene flow reduction. As a result, population fitness decreases, and the possibility of extinction increases. Polylepis (Rosaceae) forests are endemic to the Andes and their distribution reflects hundreds of years of human activities. Polylepis microphylla is the most endangered species of the genus in Ecuador and is represented by only two known forests in Chimborazo province, separated from each other by 1,6 km. The present study focused on i) exploring the genetic structure and connectivity, ii) analyzing the genetic diversity patterns in these two forests of P. microphylla. Parameters such as Fixation index, molecular variance (AMOVA) and genetic diversity estimators were calculated from the haplotypic sequences of one chloroplastic DNA region (trnG intron), one nuclear DNA region (ITS), and the concatenation of both. We found that DNA regions used were highly polymorphic with a total of nine, four and thirteen segregation sites, respectively, and nine, six and fifteen haplotypes, respectively. Also, we detected that both forest work as a single population unit due to low fixation index values (Fst = 0,03822, -0,03883 and -0,00469, respectively), which indicate high gene flow between these two forests. In addition, we detected high genetic diversity reflected by haplotype diversity in both forest (hd = 0,54204, 0,63664 and 0,81682, respectively). Likewise, haplotype relationships were visualized in networks, which demonstrated limited spatial structuring between haplotypes, corroborating the low genetic differentiation among these forests. In conclusion, our results suggest there is a single population unit of P. microphylla in Ecuador. Habitat fragmentation does not seem to have negative effects on the genetic diversity of this species. Nevertheless, the species may be vulnerable to rapid environmental fluctuations despite having relatively high genetic diversity. Its long generational time causes increased susceptibility of P. microphylla to environmental changes and may eventually lead to the extinction of the species in Ecuador. [ABSTRACT FROM AUTHOR]

New field and petrographic observations, whole-rock major- and trace-element geochemical data, Nd and Sr isotope systematics and U-Pb SHRIMP zircon ages of the Peltetec metaophiolite and related rocks (Ecuador) allow the characterization of the igneous and sedimentary protoliths and the evaluation of the geodynamic evolution of the active western margin of Gondwana during the Mesozoic. The Peltetec ophiolitic belt, exposed along the western margin of the Cordillera Real (Ecuador) and previously considered of Cretaceous age, comprises slices of metamorphosed (greenschist facies) and variably deformed peridotites, gabbros (locally cumulate), basaltic lavas and dykes, hydrothermal breccias and sedimentary rocks. The geochemical characteristics of the tholeiitic basaltic rocks indicate a Sr-Nd isotope depleted mantle source with variable imprint of subduction zone-derived or continental crust-assimilated components, as indicated by enrichment in Th, negative anomaly of Nb and relative depletion in high field strength elements (HFSE). Geochemical diversity allows defining different groups of noncumulate igneous rocks with oceanic island arc and NMORB-like back-arc affinities. U-Pb zircon ages from a metabasite yielded 228.1 ± 1.7 Ma, interpreted as the crystallization age of the magma. These data allow proposing the generation of the Peltetec ophiolite in a back-arc setting as a consequence of late Triassic extension of the western continental margin of Gondwana. Granites located at the western margin of the Peltetec Unit with S-type affinity and equal Triassic age (U-Pb age of 228.2 ± 0.8 Ma) document coeval anatexis of the continental crust as a consequence of heating associated with the same extensional event that originated the ophiolite. Geologic correlation allows enlarging such tectonic scenario to include ophiolitic units of similar age in Colombia. [ABSTRACT FROM AUTHOR]

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Reconstructions of the plate tectonic history of a continental margin are rarely unique. Comments on my recent contribution point out statements that the commentators considered confusing and misleading. The comments essentially focus on the significance, or not, of the Chilenia terrane and coeval magmatism in Argentina and to the south of the area which is the focus of my contribution. I offer here a perspective on this issue. [ABSTRACT FROM AUTHOR]