Seasonal differences in trace metal concentrations in the major rivers of the hyper-arid southwestern Andes basins of Peru.

The southern rivers of Peru originate in the Andes Mountains and flow in a southwestern direction to the Pacific Ocean through one of the most hyper-arid regions of the world. During each sub-equatorial summer from December to February, rains and snow melt in the Andes increase the streamflow in these rivers, even as they pass through the 100 km arid zone to the ocean. This study quantified seasonal dynamics of 34 trace metal elements (TM) and other constituent concentrations in four southern river basins of Peru (Chili-Quilca, Tambo, Camana-Majes-Colca, and Ocoña) during 2019-2020. Consistent with previous studies, we observed that: (1) the river water in the southern basins had relatively high concentrations of B, As, Fe, Al, Mn, P, Pb and Ni, with As the most ubiquitous toxic TM in all the basins, often detected at concentrations surpassing Peruvian and USEPA regulated concentrations; and (2) basins with the most to least toxic TM contamination were the Tambo > Chili-Quilca > Camana-Majes-Colca > Ocoña. Seasonal streamflow strongly influenced the concentrations of twenty TM, with 15 TM (Al, Au, Ba, Cd, Co, Cu, Fe, Gd, Mn, Ni, P, Pb, Ti, Yb and Zr) consistently higher in the wet season, and with As, B, Ge, Li, and Pd higher in the dry season. Our results improve the understanding of seasonal variability and vulnerability in western Andes superficial water sources, which are highly influenced by both local geogenic and anthropogenic conditions. A Spanish translation of this paper is available in the online Supplementary Material.

Characterization of medium and small-scale gold processing operations, wastewaters, and tailings in the Arequipa region of Peru.

Gold cyanidation facilities in the Arequipa Region of Peru are challenged by the availability and quality of water for processing in an arid environment. The facilities reuse decant water which recycles residual cyanide but also undesirable constituents. To understand the impact of intensive water recycling on cyanide and metals concentrations, we collected barren water, decant water, and tailings samples from six gold cyanidation facilities with ore capacities of 10-430 tons per day. Processing facilities in Arequipa recycle all effluents, with decant waters making up 58 ± 11 % of process waters. Decant water contained non-target metals: copper (394 ± 161 mg/L), iron (59 ± 34 mg/L), and zinc (74 ± 42 mg/L). In addition, decant water mean free and complexed cyanide concentrations were 534 ± 129 mg/L and 805 ± 297 mg/L, respectively. Complexed cyanide concentrations remained more constant than free cyanide concentrations with 786 ± 299 mg/L for barren water and 805 ± 297 mg/L for decant water. Cyanide mass balances showed between 21 % and 42 % of unaccounted free cyanide from the start of gold cyanidation and discharge to the tailings storage facility (TSF). Free cyanide estimated losses due to volatilization were 0.8 kg and 2.5 kg of hydrogen cyanide per ton of ore processed at barren water pH of 10.1 and 9.7. Together these results indicate two acute hazards: 1) volatilization of free cyanide during processing and 2) loading and retention of cyanides and metals into TSFs. This study elucidates the extent of uncontrolled vapor phase cyanide release during gold processing operation and contaminant concentrations in the tailings storage facilities. The data highlights the need for improvement oversight, accountability, and regulation of gold processing facilities practicing intensive recycling and zero discharge.

Biological characteristics of the Trypanosoma cruzi Arequipa strain make it a good model for Chagas disease drug discovery.

Trypanosoma cruzi, the causative agent of Chagas disease (CD), is a genuine parasite with tremendous genetic diversity and a complex life cycle. Scientists have studied this disease for more than 100 years, and CD drug discovery has been a mainstay due to the absence of an effective treatment. Technical advances in several areas have contributed to a better understanding of the complex biology and life cycle of this parasite, with the aim of designing the ideal profile of both drug and therapeutic options to treat CD. Here, we present the T. cruzi Arequipa strain (MHOM/Pe/2011/Arequipa) as an interesting model for CD drug discovery. We characterized acute-phase parasitaemia and chronic-phase tropism in BALB/c mice and determined the in vitro and in vivo benznidazole susceptibility profile of the different morphological forms of this strain. The tropism of this strain makes it an interesting model for the screening of new compounds with a potential anti-Chagas profile for the treatment of this disease.

An Endemic and Endangered New Species of the Lizard Liolaemus montanus Group from Southwestern Peru (Iguania: Liolaemidae), with a Key for the Species of the L. reichei Clade.

The southwestern Andes of Peru harbor a hidden taxonomic diversity of reptiles. We describe a new species of Liolaemus Wiegmann (Iguania: Liolaemidae) from xerophytic environments of the southwestern slopes of the Andes of Peru, 2,400-2,900 m asl. The new species, previously considered to be a population of L. insolitus Cei, exhibits unique diagnostic characters of morphology, scalation and color pattern, and molecular evidence that suggest that it belongs in the Liolaemus montanus species group and the L. reichei clade. Moreover, the species is endemic to the eastern slopes of La Caldera batholith in the Department of Arequipa, southern Peru. We also provide information on the conservation status of the species and suggest it be included in the IUCN red list of the threatened species as endangered (EN). A key for the species of the L. reichei clade is provided.

PM10 correlates with COVID-19 infections 15 days later in Arequipa, Peru.

The emergence of COVID-19 and the spread of this novel disease around the world in 2020 has entailed several cultural changes; some of those changes are positive for the environment, such as the decrease in the concentration of atmospheric particulate matter. We compared the concentrations of PM2.5 and PM10 recorded in October and November 2019 (pre-pandemic period) with the concentrations recorded from May to October 2020 (pandemic period) in the city of Arequipa, Peru. A significant decrease in the concentration of PM2.5 (less than 21.0%) and PM10 (less than 21.5%) was observed on Sundays, when population movement was strongly restricted. First, we observed a significant correlation between PM2.5 and PM10 concentration in the atmosphere and the number of infections reported in Arequipa, Peru. However, when we removed the data of Sundays from the database, these correlations were no longer significant. Subsequently, we correlated PM2.5 and PM10 concentrations with the number of COVID-19 infections on the same day and up to a 20-day delay and found that from day 15 to day 18, PM10 concentration was significantly correlated with COVID-19 infections, suggesting that SARS-CoV-2 might circulate attached to the coarse particle (PM10) and that this fraction would act as infection vector. However, these results may reflect other factors, such as social or economic factors that could explain the dynamics of infection in Arequipa, Peru. Further research is needed to better understand the dynamics of the SARS-CoV-2 pandemic.

Phyllocnistis furcata sp. nov.: a new species of leaf-miner associated with Baccharis (Asteraceae) from Southern Peru (Lepidoptera, Gracillariidae).

The southwestern Andes of Peru harbors a hidden taxonomic diversity of Lepidoptera. Here a new leaf-mining species of Gracillariidae (Lepidoptera) is described, Phyllocnistis furcata Vargas & Cerdeña, sp. nov., from a dry Andean valley of southern Peru, at 2400 m above sea level. The morphological aspects of adults (male and female) and the immature stages associated with Baccharis alnifolia Meyen & Walp. (Asteraceae) are given, under optical microscopy and scanning electron microscopy. DNA barcodes show that its nearest neighbor is the Atlantic Forest species Phyllocnistis ourea Brito & Moreira, 2017 that feeds on Baccharis anomala DC. The importance of morphological characters from immature stages for diagnosis among congeneric species is also discussed. Phyllocnistis furcata represents the fourth species of Phyllocnistis Zeller for Peru, and first record from the south of Peru for the genus.

A new species of Mathania Oberthür, 1890 from Peru (Lepidoptera, Pieridae).

A new species of the genus Mathania Oberthür, 1890, M. hughesi Lamas, Farfán Cerdeña, sp. n. is described from the southwestern slopes of the Andes of Peru, associated with xerophytic environments, between 2300 and 3500 m elevation. This new species is distinguishable from its congeners by the following external character: a black band on forewing dorsal surface at the end of the discal cell, extending from the costal margin to the base of cell M3-CuA1. Adults and male and female genitalia are illustrated and compared to other species of Mathania. In addition, we report Ligaria cuneifolia (R. et P.) Tiegh. (Loranthaceae) as host plant of M. hughesi.

Health risk assessment of polycyclic aromatic hydrocarbons (PAHs) adsorbed in PM2.5 and PM10 in a region of Arequipa, Peru.

The concentrations of PM2.5 and PM10, as well as those of the PAHs bound to these particles, were quantified at four sites in the region of Arequipa, Peru, during the year 2018. These samples were collected with high volume samplers, and the concentrations of the PAHs were quantified by liquid chromatography (HPLC). The values found for PM2.5 and PM10 at all the sampling sites in Arequipa exceeded the norms established in Peru (50 µg m-3 annual average value for PM10 and 25 µg m-3 annual average value for PM2.5), with the industrial site presenting the highest values of particulate matter (PM10 max = 235.1 µg m-3; PM2.5 max = 218.4 µg m-3). With respect to seasonality, in the cold season (winter), the concentration of particles was higher compared to the other seasons. Concerning the PAHs, it was found that these had the highest concentrations at the industrial site, followed by the site with high vehicular traffic, with both these sites differing significantly from the rural sites. In addition, at the industrial and high traffic sites, there was a predominance of PAHs with 5 and 6 rings, whereas at the rural sites, PAHs with fewer rings predominated. Finally, the calculated values of lifetime lung cancer risk also revealed a difference between sites with marked emission sources, where irrigation was considered moderate, and the rural sites, where irrigation was considered low. This demonstrated that people living at sites with mobile sources and/or industries had a higher cancer risk compared to the inhabitants of rural sites.

Estatus taxonómico de Talides basistrigata Eaton, 1932 (Lepidoptera, Hesperiidae) y su reincorporación basados en una evaluación integrativa

Talides basistrigata Eaton, 1932, originalmente descrita de Perú, posteriormente fue transferida por Evans (1955) al género Hylephila Billberg, 1820, y considerada como una subespecie de H. phyleus (Drury, 1773), argumentando que basistrigata ocurre en ambientes más secos que los que habita phyleus. Actualmente se mantiene el rango taxonómico propuesto por Evans. El objetivo del presente trabajo es restituir el estatus taxonómico de especie válida para basistrigata con base en un análisis integrativo considerando aspectos morfológicos, ecológicos y genéticos. Se examinó las estructuras genitálicas en ejemplares de basistrigata y phyleus, se obtuvo secuencias del gen mitocondrial COI para ambas especies y se recopiló datos en campo para conocer su comportamiento de oviposición en los alrededores de Arequipa, suroeste de Perú. Como resultado del examen morfológico se halló diferencias notorias entre las estructuras genitálicas de ambas especies, principalmente en los procesos caudales de las valvas, la disposición de las pectinas y la forma del uncus en los machos. Con relación al análisis genético, se halló una distancia genética mayor a 3% entre ambas especies, apoyando así el estatus taxonómico de especie para basistrigata. Adicionalmente, desde una perspectiva ecológica, se registró que ambas especies utilizan distintos mecanismos de oviposición y diferentes plantas hospederas, exhibiendo además simpatría espacial y sincronía temporal en la vertiente occidental de los Andes en Perú. Se redescribe el macho y hembra adultos de basistrigata y se designa su lectotipo.

Talides basistrigata Eaton, 1932, originally described from Peru, was subsequently transferred to the genus Hylephila Billberg, 1820 by Evans (1955) and considered a subspecies of H. phyleus (Drury, 1773), arguing that basistrigata inhabits drier environments than phyleus. Currently, the taxonomic status proposed by Evans is retained. The aim of this study is to reinstate the taxonomic status of valid species for basistrigata based on an integrative analysis considering morphological, ecological, and genetic aspects. Genitalic structures were examined in specimens of both basistrigata and phyleus, mitochondrial COI gene sequences were obtained for both species, and field data were collected to understand their oviposition behaviour in the vicinity of Arequipa city, southwestern Peru. As a result of the morphological examination, notable differences were found between the male genitalia structures of both species, primarily in the caudal processes of the valvae, the arrangement of the pectines, and the shape of the uncus. Regarding the genetic analysis, a genetic distance of greater than 3% was observed between the two species, thus supporting the taxonomic status of species for basistrigata. Additionally, from an ecological perspective, it was recorded that both species employ distinct oviposition mechanisms and different host plants, exhibiting spatial sympatry and temporal synchrony on the western slope of the Andes in Peru. Male and female adults of basistrigata are redescribed, and a lectotype is designated.

Magmatic gas percolation through the old lava dome of El Misti volcano.

The proximity of the major city of Arequipa to El Misti has focused attention on the hazards posed by the active volcano. Since its last major eruption in the fifteenth century, El Misti has experienced a series of modest phreatic eruptions and fluctuating fumarolic activity. Here, we present the first measurements of the compositions of gas emitted from the lava dome in the summit crater. The gas composition is found to be fairly dry with a H2O/SO2 molar ratio of 32 ± 3, a CO2/SO2 molar ratio of 2.7 ± 0.2, a H2S/SO2 molar ratio of 0.23 ± 0.02 and a H2/SO2 molar ratio of 0.012 ± 0.002. This magmatic gas signature with minimal evidence of hydrothermal or wall rock interaction points to a shallow magma source that is efficiently outgassing through a permeable conduit and lava dome. Field and satellite observations show no evolution of the lava dome over the last decade, indicating sustained outgassing through an established fracture network. This stability could be disrupted if dome permeability were to be reduced by annealing or occlusion of outgassing pathways. Continued monitoring of gas composition and flux at El Misti will be essential to determine the evolution of hazard potential at this dangerous volcano.

Una nueva especie de Liolaemus (Iguania: Liolaemidae) perteneciente al grupo L. montanus en las lomas costeras del sur de Perú

El género Liolaemus presenta una gran diversidad entre los tetrápodos actuales, al punto de corresponder al segundo género con mayor número de especies válidas descritas del infraorden Iguania. En este trabajo, se describe una nueva especie de lagartija arenícola perteneciente al subgénero Eulaemus, grupo de Liolaemusmontanus, procedente de las lomas costeras de Quilca, La Chira y Ocoña, todos en la provincia de Camaná, departamento de Arequipa, Perú. Para determinar el estatus taxonómico de esta nueva especie, analizamos los caracteres morfológicos, moleculares y geográficos. Los caracteres morfológicos permitieron la caracterización y diagnóstico de la nueva especie, los moleculares fueron utilizados para realizar una inferencia bayesiana y los geográficos para determinar potenciales áreas de distribución. Este reptil se diferencia de las otras especies del grupo Liolaemusmontanus en su tamaño pequeño a mediano, su conjunto de caracteres morfológicos, folidosis y patrón de coloración: es la única especie del género donde los machos tienen un patrón de manchas laterales de forma redondeada con borde oscuro e interior verde desde las axilas hasta la mitad del cuerpo. Del mismo modo, los resultados filogenéticos moleculares realizados con el gen Cyt-b indican que no tiene relación directa con las especies fenéticamente similares descritas para el grupo. Sin embargo, existe una relación con poblaciones geográficamente cercanas que permanecen taxonómicamente innominadas. Finalmente, se determinó que esta lagartija tiene un endemismo muy marcado y sus poblaciones son poco abundantes.

The genus Liolaemus presents great diversity among the current tetrapods. It is the second genus with the highest number of valid species described of the Iguana infraorder. In this study, we described a new species of sand lizard from the coastal lomas of Quilca, La Chira and Ocoña that belongs to the subgenus Eulaemus and group of Liolaemus montanus, all in the province of Camaná, department of Arequipa, Peru. To determine the taxonomic status of this new organism, we analyzed morphological, molecular and geographical characters. The morphological characters allowed the characterization and diagnosis of the new species, the molecular data was used to make a Bayesian inference, and the geographic data served to determine potential distribution areas. This lizard diverges from the other species of the Liolaemus montanus group for its small to medium size, several sets of morphological characters, folidosis and color pattern. It is also the only species of the genus where the males have a pattern of lateral spots of rounded shape with dark border and green interior, from the armpits to the middle of the body. Additionally, the molecular phylogenetic results made with the Cyt-b gene indicate that it has no direct relationship with the phenetically similar species described for the group; nevertheless, there is a relationship with geographically close populations, which has not been properly described. Finally, it was determined that this lizard has a very marked endemism and its populations are not abundant.

Bistriopelma fabianae, una nueva especie de tarántula (Araneae: Theraphosidae: Theraphosinae) de un bosque de Queñua en el sur de Perú / Bistriopelma fabianae, a new species of tarantula (Araneae: Theraphosidae: Theraphosinae) in a Queñua forest from southern Peru

Resumen Se describe, diagnostica e ilustra una nueva especie de Bistriopelma Kaderka 2015, Bistriopelma fabianae sp. nov., para la región de Arequipa en el sur de Perú. Los especímenes se encontraron en un bosque de Queñua (Polylepis rugulosa Bitter) ubicado en las faldas del volcán Pichu Pichu en la zona de amortiguamiento de la Reserva Nacional de Salinas y Aguada Blanca. Se presentan datos biológicos y ecológicos de B. fabianae sp. nov. y también notas adicionales sobre B. kiwicha y B. peyoi, dos nuevas especies recientemente descritas de las regiones de Apurímac y Cusco.

Abstract A new species of Bistriopelma Kaderka 2015, Bistriopelma fabianae sp. nov., from the Arequipa region in southern Peru is described, diagnosed, and illustrated. Specimens were found in a Queñua forest (Polylepis rugulosa Bitter) spread out on the slopes of Pichu Pichu volcano in the buffer zone of Salinas and Aguada Blanca National Reserve. Biological and ecological data of B. fabianae sp. nov. are provided as well as notes on B. kiwicha and B. peyoi, two new species recently described from Apurimac and Cusco regions.

Ampliación del rango de distribución de la cotinga cariblanca Zaratornis stresemanni (Aves: Cotingidae) en el sur del Perú / Distribution range extension of the White-cheeked Cotinga Zaratornis stresemanni (Aves: Cotingidae) in southern Peru

La cotinga cariblanca Zaratornis stresemanni (Koepcke, 1954) (Aves: Cotingidae) es un ave endémica del Perú especialista de bosques de Polylepis. Actualmente se encuentra amenazada por la pérdida y degradación de su hábitat. En esta nota reportamos dos registros documentados al noroeste del departamento de Arequipa, en el sur de Perú, los cuales amplían en al menos 130 km su rango de distribución austral y corresponden a los primeros registros documentados de la especie para el departamento de Arequipa. Se sugiere que la cotinga cariblanca residiría en los bosques de Polylepis en el noroeste de Arequipa.

The White-cheeked Cotinga Zaratornis stresemanni (Koepcke, 1954) (Birds: Cotingidae) is an endemic bird of Peru, specialist of Polylepis forests. Is currently threatened by habitat loss and degradation. In this note, we document records to the northwest of Arequipa department, in southern Peru. These records extend in at least 130 km the austral distribution range and correspond to the first documented records of the species for Arequipa department. We suggest that the White-cheeked Cotinga would be resident in the Polylepis forests in northwest Arequipa.

Mariposas (Lepidoptera: Papilionoidea) de Arequipa, Perú: Lista preliminar con dos nuevos registros para Perú / Butterflies (Lepidoptera: Papilionoidea) of Arequipa, Peru: A checklist, with two new records from Peru

Se presenta una lista de 74 especies de mariposas diurnas registradas para el Departamento de Arequipa, Perú. Se reporta por primera vez para Perú las especies Strymon flavaria (Ureta 1956) e Hylephila herrerai MacNeill 2002, ambas descritas del norte de Chile. Se suministran datos de distribución local para cada una de las especies. Se brindan comentarios para aquellas especies citadas en la literatura para el Departamento de Arequipa y que fueron excluidas de la presente lista preliminar por errores de identificación y/o ubicación geográfica.

A list of 74 butterfly species recorded until present at the Arequipa Department, Peru, is presented herein. Two new records from Peru of Strymon flavaria (Ureta 1956) and Hylephila herrerai MacNeill 2002 are reported herein, both described from northern Chile. Comments for species cited to Arequipa in the literature and that were excluded from this preliminary list are provided.