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Janthina and Recluzia species are pleustonic snails that feed on cnidarians and can be easily differentiated by their shells, which are of a striking purple to violet-blue hue in Janthina, and whitish to brownish in Recluzia. In the southeastern Pacific off Chile, four of the five extant Janthina species and a single species of Recluzia have been recorded. In this work, we present new records for Janthina janthina (Linnaeus, 1758) for specimens collected at San Felix Island, in the Desventuradas Islands, and for Recluzia lutea (Bennet, 1840) for a specimen collected at Robinson Crusoe Island, in the Juan Fernandez Archipelago. These records fill a gap in the geographical distribution of J. janthina in the southeastern Pacific and extend the distribution of R. lutea in about 3000 km from its previous record at Easter Island, being the most easterly record for the species.

Lasia pulla has not recorded since their description in 1865 by Philippi. New specimen records and an updated taxonomical description is provided here. This hummingbird fly species is endemic from the Los Ríos Region, Chile. In this area, many ecosystems are still unexplored, but anthropic activities are currently fragmenting the evergreen forests. A IUCN Red List assessment is suggested.

The first record of the epibiont cirripedium of sea turtles, Chelonibia testudinaria (Linnaeus, 1758), is described for northern Chile (the second record for the species in the country), extending the distribution of this species by almost 10 latitudinal degrees (about 1020 km), and filling a gap in its geographic range in the southeastern Pacific.

Introducción: la Macroglobulinemia de Waldenström (MW) es un tipo raro de linfoma de células B caracterizado por la proliferación de células linfoplasmocíticas que secretan altas cantidades de inmunoglobulinas M (IgM) monoclonales. Puede presentarse con una amplia gama de síntomas, entre ellos los derivados del aumento de la viscosidad plasmática. Métodos: reportamos un caso de MW que presentó una trombosis de la vena central de la retina (TVCR) bilateral en el contexto de un síndrome de hiperviscosidad (SHV). El objetivo de este trabajo fue revisar algunos aspectos clínicos de la MW, con especial énfasis en el SHV y la TVCR. Resultados: las manifestaciones clínicas y de laboratorio de la MW son inespecíficas y comunes a otras neoplasias hematológicas. El SHV se produce cuando los niveles de IgM sobrepasan los 3 mg/dL, situación que ocurre en un 15-30% de los pacientes. La TVCR es una complicación grave y rara asociada al SHV, presentándose típicamente como una pérdida de agudeza visual indolora. El fondo de ojo exhibe signos característicos, como tortuosidad venosa y hemorragias retinales hasta la periferia, y la angiografía con fluorosceína y la OCT pueden orientar al diagnóstico y guiar el manejo. El tratamiento incluye la plasmaféresis y tratamientos oftalmológicos basados en agentes antioangiogénicos. Conclusión: la MW es una enfermedad incurable. Sin embargo, es importante sospechar una TVCR en pacientes que debutan con una pérdida de agudeza visual, ya que existen tratamientos efectivos en el manejo de esta complicación.

The Molluscan species of the northern littoral of Chile have been sparsely studied. This work reviews for the first time the diversity of polyplacophoran molluscs around the port of Caldera, in the Region of Atacama (26°45’49”S; 70°45’17”W to 27°20’23”S; 70°56’46”W), northern Chile. Eleven species were found in this study: Acanthopleura echinata (Barnes, 1824); Callistochiton pulchellus (Gray, 1828); Calloplax vivipara (Plate, 1899), Chaetopleura peruviana (Lamarck, 1819); Chiton cumingsii Frembly, 1827; Chiton granosus Frembly, 1827; Chiton magnificus Deshayes, 1827; Enoplochiton niger (Barnes, 1824), Radsia barnesii (Gray, 1828), Tonicia atrata (G. B. Sowerby II, 1840) and Tonicia chilensis (Frembly, 1827). All of the species occurring in the area have distributions in the southeastern Pacific Ocean, from Ecuador to central Chile, and three of them are species endemic to the Chilean coasts (Calloplax vivipara, Radsia barnesii, and Tonicia atrata). This diversity of species is comparable to that of better surveyed faunas of central and southern Chile or Patagonia. Of the eleven species recorded, the geographic distribution records for Callistochiton pulchellus, Radsia barnesii and Tonicia atrata are extended, and Calloplax vivipara is found alive again after 40 years, filling a gap in its known distribution. Illustrations of living specimens in their habitat, distribution records and a taxonomic key for all the studied taxa are also provided.

Deep waters of the South Pacific off northern Chile remain poorly studied, particularly in regard to invertebrate faunas. Some recent works include new records on deep-water species, mostly from the bycatch of benthic fisheries concentrated along the continental margin of the country. Among these, a few specimens of an unidentified bathylasmatine balanomorph were collected off Caldera, northern Chile, and they are described here as Bathylasma chilense sp. nov. While this is the second report of a bathylasmatid in the Eastern Pacific Ocean, the first being Tetrachaelasma southwardi Newman & Ross, 1971, it is not only the first but the deepest known (1800-2000 m) species of Bathylasma. Its discovery increases the number of described Bathylasma species to eight, four of which are extant. This is the third deep-water balanomorph cirriped recorded for the region where it may represent an isolate from a West Wind Drift fauna, an immigrant from the western Pacific, or a relict of a once cosmopolitan Paleocene-Eocene fauna now having an amphitropical component.

Deep-sea fishing bycatch enables collection of samples of rare species that are not easily accessible, for research purposes. However, these specimens are often degraded, losing diagnostic morphological characteristics. Several tubes of vestimentiferans, conspicuous annelids endemic to chemosynthetic environments, were obtained from a single batch of deep-sea fishing bycatch at depths of around 1,500 m off Huasco, northern Chile, as part of an ongoing study examining bycatch species. DNA sequences of the mitochondrial cytochrome c oxidase subunit I (COI) gene and an intron region within the hemoglobin subunit B2 (hbB2i) were successfully determined using vestimentiferans' dried-up tubes and their degraded inner tissue. Molecular phylogenetic analyses based on DNA sequence identified the samples as Escarpia spicata Jones, 1985, and Lamellibrachia barhami Webb, 1969. These are the southernmost records, vastly extending the geographical ranges of both species from Santa Catalina Island, California to northern Chile for E. spicata (over 8,000 km), and from Vancouver Island Margin to northern Chile for L. barhami (over 10,000 km). We also determined a 16S rRNA sequence of symbiotic bacteria of L. barhami. The sequence of the bacteria is the same as that of E. laminata, Lamellibrachia sp. 1, and Lamellibrachia sp.2 known from the Gulf of Mexico. The present study provides sound evidence forthe presence of reducing environments along the continental margin of northern Chile.

A new species of Scutalus Albers, 1850 (Gastropoda: Bulimulidae), Scutalus chango sp. n., is described from a coastal area of northern Chile. Empty shells of this new species were found buried in sand and under boulders and rocks in the foothills of the Chilean Coastal Range at Paposo, Región de Antofagasta. This new species is distinguished from all other Chilean terrestrial snails by its slender shell with a flared and reflected aperture, and by the presence of a columellar fold. This is the first record of Scutalus in Chile, and the southernmost record for this endemic South American bulimulid genus. The presence of this species in Paposo highlights the need for further research and for conservation guidelines in coastal areas of northern Chile, which have comparatively high levels of biodiversity and endemism.

The objective of this work was to estimate the (co)variance and the genetic parameters for weight and average daily gain from two national generations of the GIFT strain of the Nile tilapia (Oreochromis niloticus). We evaluated 3918 fish from two generations of the breeding program from the Universidade Estadual de Maringá, Northwestern Paraná. Univariate and bivariate analysis were carried out using Bayesian inference. The estimates of heritability using one-trait models for weight was 0.15, average daily gain was 0.19, fish length was 0.23, fish width was 0.19, standard length was 0.17, fish height was 0.15, and the head length was 0.17. The genetic and phenotypic correlations were above 0.68 and 0.95, respectively. The values of Spearman and Pearson correlations for breeding values of the morphometric traits in relation to average daily gain ranged from 0.58 to 0.98 and from 0.63 to 0.99, respectively. In the second generation (G2), the genetic gain was 2.6%, the effective size of the population was 94, and the inbreeding coefficient was 0.005. In the next generation (G3), these values were 8.1%, 124 and 0.004, respectively. The genetic gains over the generations gradually increased from one generation to another, indicating that the criterion, average daily gain, chosen for feature selection was efficient.

Terrestrial mollusca are sparsely studied in Chile and, for the first time, a formal record of the diversity of land snails in northern Chile is reported. Coastal and desertic areas in the Region of Atacama, in the border of the Atacama desert and the Pacific Ocean, were surveyed with the aim to describe the presence and distribution of this poorly known fauna. Of the fourteen species recorded, the geographic distribution records for nine species are extended, and some taxa are recorded for the first time since their original descriptions. All, except one, of the fourteen terrestrial molluscan species occurring in the area are endemic to Chile; they are all terrestrial species, most of them have a restricted geographic distribution, and none of them is currently protected by law. The results reveal that the region of Atacama has one of the most diverse terrestrial snail biodiversity in Chile, ranking only after the Juan Fernandez Archipelago. Distribution records of all the studied species and a taxonomic key are also provided.

INTRODUCCIÓN: la solución en la que se almacenan los discos de dentina mientras son estudiados, ha determinado ser vital para reproducir condiciones posibles de encontrar “in vivo”, y finalmente resulta crítica en la evaluación de cualquier estudio relativo a la conductancia hidráulica. El objetivo de este estudio fue determinar in vitro la variación en la tasa de filtración transdentinaria en discos de dentina humana, luego de 2,4,6,7,14,21 y 28 días almacenados en HBSS(Hank’s Balanced Salt Solution), formalina al 10% y suero fisiológico. MÉTODOS:se utilizaron 41 terceros molares humanos sanos en inoclusión. Estos dientes fueron desinfectados en Timol al 0,1% por 24 horas, para luego ser incluidos en bloques de resina epóxica. Estos fueron cortados de manera que se lograran discos de dentina de 1 mm de grosor. Posterior a esto, a los discos dentinarios se les midió su conductancia hidráulica, luego fueron separados para ser almacenados en diferentes medios. Se conformaron los siguientes grupos: 1)formalina al 10%; b) solución de Hank (HBSS) y c)suero fisiológico. Luego se midió su conductancia hidráulica luego de 1, 2, 4, 6, 7, 14, 21 y 28 días. El análisis estadístico fue por ANOVA y post hoc de Tukey (SPSSv15). RESULTADOS: : los resultados obtenidos indicaron que las medias de los discos dentinarios, en todas las soluciones de almacenamiento, aumentaron su conductancia hidráulica comparando el día de corte y el día 28 de análisis. CONCLUSIONES: no existieron diferencias significativas (p > 0,005) de conductancia hidráulica entre los diferentes días de los discos almacenados en solución de Hank.

A new species of the genus Aeneator Finlay, 1926 is described from off the coast of Caldera (27°S), northern Chile. Aeneator martae sp. n. has a small, broad, stout, angulated shell with more prominent axial ribs and a more obviously keeled periphery than all previously named Chilean species. Comparisons are provided with all other South American named species of Aeneator.

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The coast of northern Chile has been sparsely studied in regards to its invertebrate fauna, with just a few works reviewing the distribution of local mollusks. This work presents a survey of the shallow water heterobranch sea slugs currently occurring around the port of Caldera (27 °S), in the Región de Atacama, northern Chile. Eight species of sea slugs were found in this study: Aplysiopsis cf. brattstroemi (Marcus, 1959), Baptodoris peruviana (d’Orbigny, 1837), Diaulula variolata (d’Orbigny, 1837), Doris fontainii d’Orbigny, 1837, Onchidella marginata (Couthouy in Gould, 1852), Phidiana lottini (Lesson, 1831), Tyrinna delicata (Abraham, 1877) and the new species Berthella schroedli sp. nov., described herein. All of the species found in the area are endemic to South America, having distributions in the southeastern Pacific and South Atlantic Oceans, from Ancash, Perú to Peninsula Valdés, Argentina, and two of them represent species which are endemic to the Chilean coasts (Aplysiopsis cf. brattstroemi and Berthella schroedli). The finding of a previously undescribed species emphasizes the need of further surveys, particularly in subtidal and deeper waters, in order to improve the knowledge on this neglected fauna in Atacama.

The bulimulid genus Bostryx Troschel, 1847 is the most species-rich genus of land snails found in Chile, with the majority of its species found only in the northern part of the country, usually in arid coastal zones. This genus has been sparsely studied in Chile and there is little information on their distribution, diversity or ecology. Here, for the first time, a formal analysis of the diversity of bulimulids in the Región de Atacama, northern Chile, is reported. Of the seventeen species recorded for the area, most of them were efectively found in the field collections and one record was based on literature. Five taxa are described as new: Bostryx ancavilorum sp. nov., Bostryx breurei sp. nov., Bostryx calderaensis sp. nov., Bostryx ireneae sp. nov. and Bostryx valdovinosi sp. nov., and the known geographic distribution of seven species is extended. Results reveal that the Región de Atacama is the richest region in terrestrial snails in Chile, after the Juan Fernández Archipelago. All of the terrestrial molluscan species occurring in the area are endemic to Chile, most of them with restricted geographic distributions along the coastal zones, and none of them are currently protected by law. Further sampling in northern Chile will probably reveal more snail species to be discovered and described.

The extreme dependence on external oxygen supply observed in animals causes major clinical problems and several diseases are related to low oxygen tension in tissues. The vast majority of the animals do not produce oxygen but a few exceptions have shown that photosynthetic capacity is physiologically compatible with animal life. Such symbiotic photosynthetic relationships are restricted to a few aquatic invertebrates. In this work we aimed to explore if we could create a chimerical organism by incorporating photosynthetic eukaryotic cells into a vertebrate animal model. Here, the microalgae Chlamydomonas reinhardtii was injected into zebrafish eggs and the interaction and viability of both organisms were studied. Results show that microalgae were distributed into different tissues, forming a fish-alga chimera organism for a prolonged period of time. In addition, microscopic observation of injected algae, in vivo expression of their mRNA and re-growth of the algae ex vivo suggests that they survived to the developmental process, living for several days after injection. Moreover microalgae did not trigger a significant inflammatory response in the fish. This work provides additional evidence to support the possibility that photosynthetic vertebrates can be engineered.