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The decapod fauna in the intertidal zone of the rocky shores of Chile is highly diverse, especially along the northern and central mainland coasts, where the influence of the cold Humboldt Current results in high productivity. One of the most abundant species in these ecosystems is the decapod Cyclograpsus cinereus Dana, 1851. The aim of the present study, carried out in the spring and summer seasons between 2018 and 2020, was to determine the spatial distribution patterns of the decapod C. cinereus in different sites along the rocky shores of Antofagasta bay, northern Chile, in order to establish probabilistic models that explain its distribution at each site. Individuals were counted in random quadrants in the intertidal zone. The data thus obtained were processed by application of the variance/mean ratio to determine whether the distribution of individuals was random, aggregated or uniform, associated with Poisson, negative binomial or positive binomial distributions, respectively. The data revealed aggregated (negative binomial) distribution in 15 sampling events, and uniform (positive binomial) distribution in 4 events. The sampling sites were located on rocky shores in four sectors of an urban zone, and two in a protected zone; no significant differences were found between the densities of the sites in the two zones. The results of the interpretative probabilistic models indicated aggregated distribution patterns, agreeing with previously reported interpretative probabilistic models for the distribution of decapods on the rocky shores of central and southern Chile.

The brine shrimp Artemia in Chile has been studied since the 1980s, initially on populations inhabiting shallow coastal and inland mountain ponds, and saltworks in northern and central Chile. Based on morphometric and molecular evidence, these populations were identified as A. franciscana. In the 1990s, A. persimilis was recorded from southern Patagonia, a species previously considered endemic to Argentina. Recently, two new populations of A.franciscana have been recorded, from one saline coastal pond in northern Chile and from a saltwork in central Chile. The scope for further research to increase both understanding of the strain characterization and basic population ecology descriptions of the Chilean brine shrimps and improve their conservation status is discussed. It is suggested that future studies should investigate first the management of local brine shrimp population for local aquaculture or conservation resources, other direction would be the effects of ultraviolet radiation (UVR) exposition that is notoriously high in brine shrimp habitats. This last factor is very important because the UVR is an important mutagen on the genetic structure of the populations. In this scenario, it is suggest a carefully management for introduced brine shrimp populations for local aquaculture for avoid alterations in native populations that due their genetic isolation would need conservation procedures for avoid local extinctions.El camarón de salmuera o Artemia ha sido estudiado en Chile desde la década de 1980, las primeras descripciones de poblaciones fueron para lagunas someras en zonas costeras y de montana, y en salinas artificiales en la zona central y norte de Chile. Sobre la base de evidencias morfométricas y moleculares estas poblaciones fueron descritas como A. franciscana. En la década de 1990, se describió la presencia de A. persimilis en la zona sur de la Patagonia, lo cual fue una ampliación del rango de distribución significativa, pues esta especie se le consideró endémica de Argentina. Recientemente dos nuevas poblaciones de A. franciscana fueron reportadas en una laguna somera en el norte y para una salina artificial en la zona central. El objetivo del presente estudio fue realizar una investigación para entender la caracterización de poblaciones y ecología básica de las poblaciones chilenas del camarón de salmuera y discutir como mejorar el estado de la conservación de estas. Se discute que a futuro los estudios se deberían enfocar primero al manejo de poblaciones nativas para acuicultura local o como un recurso para su conservación, otras orientaciones de estudio, podrían ser los efectos de la radiación ultravioleta (UVR) que es notoriamente alta en los hábitats del camarón de salmuera. Este último factor es importante porque la radiación ultravioleta es un agente mutágeno importante en la estructura genética de las poblaciones. En este escenario, se sugiere un manejo cuidadoso de las poblaciones introducidas del camarón de salmuera para la acuicultura local, con el fin de evitar alteraciones en las poblaciones nativas que debido a su aislamiento genético necesitarían procedimientos para su conservación con el fin de evitar extinciones locales.

Abstract Temporary pools are freshwater bodies of significant interest due to their high species diversity, and the colonization and extinction processes observed at temporal scales. The aim of the present study was to perform a short-term ecological comparison in a group of shallow temporary pools in northern Chilean Patagonia in two periods, August and September 2018. The results revealed marked differences in terms of species richness in the study pools at different conductivities and chlorophyll a concentrations. The dominant species was the calanoid copepod Boeckella gracilis Daday, 1902, while the presence of the rare Anostracan Branchinecta rocaensis Cohen, 1982 was reported in conditions of low chlorophyll a and low conductivity. The community was studied using co-occurrence null models that revealed the absence of structured patterns in species associations, and the presence of niche overlap, with many repeated species that have a similar ecological niche. The present results are identical with observations from temporary pools in southern Chilean Patagonia.

Abstract The oyster culture has the incrusting organism as problem for production, in this context, it evaluated as biological control against incrusting organism and sediments the introduction of gastropod Tegula atra (Lesson, 1830) in Chilean oysters (Triostrea chilensis Phillippi, 1844) cultures in conditions of starvation presence and absence located in floating cages and bottom cultures. The predation and mechanic effect on T. atra grazing generated a decreasing in seven days of 19.8% and 13.7% of incrusting organisms in cage culture and bottom sediments by effects of gastropods without starvation respectively. Whereas it had a decrease of 12.6% and 11.4% of incrusting organisms in cage culture and bottom sediments by effects of gastropods with starvation respectively. The incrusting organism removed were mainly algae, colonial ascidia, polychaeta, bryozoan and small crustaceans.

Dissotichus eleginoides has a discontinuous circumpolar geographic distribution restricted to mountains and platforms, mainly in Subantarctic and Antarctic waters of the southern hemisphere, including the Southeast Pacific, Atlantic and Indian oceans and in areas surrounding the peninsular platforms of subantarctic islands. The aim of this work was to determine and characterize the gastrointestinal parasitic and microbial fauna of specimens of D. eleginoides captured in waters of the south-central zone of Chile. The magnitude of parasitism in D. eleginoides captured in waters of the south-central zone of Chile is variable, and the parasite richness is different from that reported in specimens from subantarctic environments. Next-generation sequencing (NGS) of the microbial community associated to intestine showed a high diversity, where Proteobacteria, Firmicutes, and Bacteriodetes were the dominant phyla. However, both parasitic and microbial structures can vary between fish from different geographic regions

En Chile, el principal insumo usado como alimento para abalones son las algas Gracilaria chilensis y Macrocystis pyrifera. Estas algas experimentan una notable baja de disponibilidad en otoño e invierno, lo cual trae consigo un aumento considerable de los precios, al tener que depender del abastecimiento desde áreas cada vez más alejadas de los centros de cultivo de abalones y, eventualmente, generando impactos ecológicos indirectos en sus poblaciones. El objetivo fue elaborar y evaluar un ensilado del alga G. chilensis para la alimentación de abalón rojo (Haliotis rufescens), determinando la cantidad de lixiviados generados durante el proceso, el cambio en la composición proximal del alga, la preferencia y consumo del abalón rojo de ensilado de G. chilensis. Se logró un producto ensilado de buenas características físicas, químicas y de conservación, así como una buena aceptación por parte del abalón.

The Chilean inland water crustaceans are characterized by a combination of endemic and cosmopolitan species: some occur throughout the territory of continental Chile, while others are restricted to specific latitudinal regions. This study examined the zoogeographical patterns exhibited by Chilean inland water crustaceans. We considered six regions: Northern Chile (18°-27°S), North-Central Chile (27°-30°S), Central Chile (30°-38°S), Northern Patagonia (38°-41°S), Central Patagonia (41°-51°S), and Southern Patagonia (51°-55°S), and these were identified based on literature records of inland water crustaceans. The classification analysis generated dendrograms for the following groups considered in this categories: all inland water crustaceans (Branchiopoda, Copepoda and Malacostraca), the zooplanktonic crustaceans (Branchiopoda and Copepoda), the Malacostraca alone, and each group separately. Analysis of total data and of the zooplankton group taxa alone revealed the existence of a main grouping consisting of the three Patagonian zones plus Central Chile, that is distinct from that of Northern Chile and North-Central Chile. Similarly, analysis of the malacostracan data revealed the existence of two main groups, one comprising the three Patagonian zones plus Central Chile, contrasted with a second group of Northern and North-Central Chile combined. Our results are in agreement with other panbiogeographical studies of South American crustaceans and insects. Possible factors responsible for generating this pattern are the dispersal and colonization potential of zooplanktonic crustaceans and the marked endemism of the malacostracans.

Los copépodos intermareales chilenos han sido un grupo poco estudiado, existiendo reportes aislados para el litoral de Chile central y para territorios insulares. El objetivo del presente estudio fue analizar los ensambles de especies de copépodos intermareales en territorios insulares chilenos (islas de Pascua, San Félix, Alejandro Selkirk y Robinson Crusoe) y compararlas respecto a una zona del continente (Montemar, Valparaíso), por medio de un análisis de modelo nulo de co-ocurrencia de especies y un análisis de conglomerados. Los resultados del modelo nulo indicaron, para una simulación, que hay factores reguladores, mientras que en dos simulaciones no hay factores reguladores, lo que se debería al bajo número de especies reportadas. Por otro lado, el análisis de conglomerados reportó la existencia de un grupo principal conformado por las islas Alejandro Selkirk, San Félix y Robinson Crusoe, seguido después por la isla de Pascua y finalmente por Montemar. Se analizaron tópicos ecológicos, principalmente relacionados con los patrones de regulación de la riqueza de especies, como posibles explicaciones de los resultados observados.

The increased activity of aquaculture in Chile involves cultivation of salmonids, oysters mussels and other species such, and to a lesser extent species such as red abalone (Haliotis rufescens) and Japanese abalone (Haliotis discus hannai). The aim of this study was to evaluate the growth rate of Haliotis rufescens and Haliotis discus hannai fed with different pellet based diets with Macrocystis sp. and Ulva sp., grown in ponds for 13 months. The results for both species denoted that there was an increase in length and biomass during experimental period, existing low growth rates during the austral winter (July-September) and increase during the austral summer (December-January). Results are consistent with descriptions of literature that there is high rate of growth during the summer and using diet of brown algae. From the economic standpoint abalone farming would be an economically viable activity for local aquaculture, considering the water quality and food requirements.

Chilean inland-water ecosystems are characterized by their low species-level biodiversity. This study analyses available data on surface area, maximum depth, conductivity, chlorophyll-α concentration, and zooplankton crustacean species number in lakes and ponds between 23° and 51°S. The study uses multiple regression analysis to identify the potential factors affecting the species number. The partial correlation analysis indicated a direct significant correlation between chlorophyll-α concentration and species number, whereas the multiple regression analysis indicated a direct significant response of species number to latitude and chlorophyll-α concentration. These results agree with findings from comparable ecosystems in Argentina and New Zealand.

Se realiza una revisión de las especies de anfípodos del género Hyalella en aguas continentales de la Patagonia, isla Tierra del Fuego, Reserva de la Biosfera de Cabo de Hornos e islas adyacentes (38-54°S). Esta zona austral presenta numerosos tipos de ambientes acuáticos continentales como lagos, humedales y arroyos, y las principales especies en ambientes bentónicos corresponden a anfípodos del género Hyalella. La bibliografía menciona la presencia de H. costera, H. chiloensis, H. falklandensis, H. franciscae, H. neonoma, H. patagónica, H. rionegrina y H. simplex. La distribución de estas especies concuerda con estudios biogeográficos sobre la presencia de especies endémicas y de amplia distribución en el sur de la Patagonia y zona subantárticas. A pesar de la presencia de especies depredadoras introducidas, sobre la base de la literatura, los anfípodos serían más abundantes debido a la presencia de materia orgánica particulada.This study reviews the amphipod species of the genus Hyalella in the inland waters of Patagonia, Tierra del Fuego Island, Cape Horn Biosphere Reserve, and adjacent islands (38-54°S). This southern zone has numerous kinds of continental water bodies such as lakes, wetlands, and streams, and the main species in benthic assemblages are amphipods of the genus Hyalella. The literature mentions the presence of H. costera, H. chiloensis, H. falklaidensis, H. franciscae, H. neonoma, H. patagonica, H. rionegrina, and H. simplex. The distribution of these species agrees with biogeographical studies about the presence of widespread, endemic species in southern Patagonia and the sub-Antarctic zone. In spite of the presence of introduced predatory species, the literature indicates that the amphipods are more abundant due to the presence of particulated organic matter.

Chilean Patagonia has protected mountainous areas with evergreen native forests; in which the lakes and rivers, of volcanic or glacial origin, are oligotrophic. In Bulgaria, there are mountainous zones with native forests and associated lakes of volcanic origin. The aim of the present study is to carry out a preliminary comparison of zooplanktonic crustaceans in lake ecosystems associated with native forests of Chilean Patagonia and of Bulgarian mountains. The study revealed that the lakes studied in Chilean Patagonia are associated mainly with Nothofagus forests; they are oligotrophic, with a low number of zooplanktonic crustacean species. Similar results were observed for Bulgarian mountain lakes associated with Fagus forests. A null model analysis of species co-occurrence was applied to the two groups of lakes, and the result revealed the absence of regulatory factors in species associations. These studies agree with similar descriptions of lakes in Andean Patagonia and New Zealand. They highlight the important role of native Nothofagus forests in Argentina and Chile, and of Fagus forests with associated soil properties in Bulgaria, in the oligotrophy of the lakes studied.La Patagonia de Chile tiene una serie de áreas protegidas con bosques nativos perennes asociados a lagos y ríos oligotróficos y de origen glacial. Por otro lado en Bulgaria hay una serie de zonas montañosas con lagos asociados de origen volcánico o glacial. El objetivo del presente trabajo es realizar una primera descripción de especies de crustáceos zooplanctónicos en ecosistemas lacustres asociados a bosques nativos en la Patagonia de Chile y en las montañas de Bulgaria. Los estudios indican que los lagos de la Patagonia de Chile están asociados principalmente con bosques de Nothofagus, mientras que similares resultados fueron observados en lagos de Bulgaria con bosques de Fagus. La regresión lineal entre concentración de clorofila y número de especies para lagos chilenos, fue significativa mientras que en lagos de Bulgaria el análisis de regresión no indicó diferencias significativas. Se aplicó un análisis de co-ocurrencia de especies para ambos grupos de lagos y los resultados indicaron la ausencia de factores reguladores en las asociaciones de especies. Estos estudios concuerdan con descripciones similares para lagos de la Patagonia andina y Nueva Zelanda, y remarcan el rol de los bosques nativos de Nothofagus en Argentina y Chile, así como la presencia de bosques de Fagus y las propiedades del suelo en Bulgaria, como regulador importante de la oligotrofía asociada a los lagos analizados.

The lakes studied (Tinquilco, Verde, Toro, Chico) are located in the Huerquehue National Park (39°08'S, 71°40'W), Chile. An inventory of the aquatic and riparian species was performed between December 2005 and March 2006. A null model analysis was done to determine the existence of regulatory factors of species associations, and the Jaccard index was applied to determine floristic similarities. Seventy-five species were identified. The greatest number (54) and highest percentage of introduced species (37%) occurred at Tinquilco Lake, placing it in the category of "high human disturbance". Verde Lake, on the other hand, presented the lowest number of species (21), and the percentage of introduced species did not exceed 20% in the other three lakes, which are considered to have "low human disturbance". The analysis of the null model revealed the presence of regulatory factors in one of the three simulations. However, in the other two simulations, the species associations appeared to be random, presumably because many species were repeated at the study sites. According to the Jaccard index, Tinquilco Lake is noticeably different from the other lakes, probably due to its transition from oligotrophy to mesotrophy.Los lagos estudiados (Tinquilco, Verde, Toro, Chico) se localizan en el Parque Nacional Huerquehue (39°08'S, 71°40'W). Entre diciembre de 2005 y marzo de 2006, se inventarió su flora acuática y ribereña. Para determinar la influencia de factores reguladores en las asociaciones de especies se aplicó un análisis de modelo nulo y para determinar similitudes florísticas se aplicó el índice de Jaccard. Se identificaron 75 especies, donde el mayor número (54) y el mayor porcentaje de especies introducidas (37%) se registró en el lago Tinquilco, por lo que se incluye en la categoría de "altamente intervenido"; mientras que el menor número de especies se registró en el lago Verde con 21, y el porcentaje de especies introducidas no superó el 20% en los otros tres lagos, por lo cual se consideran como "poco intervenidos". Los análisis del modelo nulo muestran la presencia de factores reguladores en una de las tres simulaciones, mientras que en las dos restantes se sugiere una asociación aleatoria de las especies, supuestamente explicada por la presencia repetida en los sitios. El índice Jaccard reveló que el Tinquilco es notablemente diferente a los otros lagos, cuya probable causa se relacionaría con la transición de oligotrofía a mesotrofía.

The brine shrimp Artemia is important for aquaculture since it is bighly nutritious. It is also used widely in biological studies because it is easy to culture. The aim of the present study is to review the literature on the taxonomical nomenclature of Artemia. The present study indicates the existence of seven species: three living in the Americas, one in Europe, and three in Asia.El camarón de salmuera Artemia es importante para la acuicultura por su alta calidad nutricional y es muy utilizado para estudios biológicos por ser de fácil cultivo. El objetivo del presente estudio es revisar la literatura sobre la nomenclatura taxonómica de Artemia. Se determina la existencia de siete especies; tres de ellas viven en América, una en Europa y tres en Asia.

The crustacean zooplankton of Chilean inland waters are characterized by abundant calanoid copepods, mainly from the gemís Boeckella. The present study aims to update the distribution of Boeckella gracilis in the inland waters of the Araucania region (38-39°S) and to use null model analysis to understand the B. gracilis species associations. In the literature for Chile, this species is reported to be found in one northern lake and in three lakes of northern Patagonia. These fmdings are complemented by reports of this species for coastal and mountain ponds and mountain lakes of the Araucania region. These results agree with descriptions of this species for South American inland waters. The results of the null model analysis reveal factors regulating the species associations, whether comparing all the inhabitats or the guild structure, although some simulations show the opposite situation due to the presence of repeated species at many sites.Los crustáceos zooplanctónicos en aguas continentales chilenas están caracterizados por la abundancia de copépodos calanoideos, principalmente del género Boeckella. El objetivo del presente trabajo es actualizar la distribución de esta especie en aguas continentales de la región de la Araucania (38-39°S), y el uso de modelos nulos para comprender sus especies asociadas. Las descripciones de la literatura indican que en Chile esta especie está en un lago del norte, y tres lagos en el norte de la Patagonia. Estos resultados están complementados con reportes de esta especie en pozas costeras, pozas y lagos de montaña en la región de la Araucania. Estos resultados concuerdan con las descripciones de esta especie para aguas continentales Sudamericanas. Los resultados del análisis de modelos nulos revelan que las asociaciones de especies tuvieron factores reguladores, ya sea comparando todos los habitantes y como estructura de gremios, aunque en algunas simulaciones se observó una situación opuesta, esto se debió a la presencia de especies repetidas en muchos sitios.

The Chilean Patagonia has numerous kinds of inland water ecosystems such as lakes, ponds, wetlands and rivers that have been poorly studied due to access difficulties. This study was carried out in Aysen region, in southern Chile, and it included different kinds of water bodies such as rivers, streams, ponds, lagoons and lakes distributed along an altitudinal gradient at 46° S. It was found a low species number, essentially cladocerans, copepods and amphipods. A null model was applied in order to determine the existence of regulator factors of species associations, and the results revealed that they are not random. The patterns would be influenced by geographical and limnological characteristics of the studied sites. Our results would agree with regional studies on habitat heterogeneity such as in Torres del Paine National Park and other zones in Tierra del Fuego island.