Induction of defences and within-plant variation on palatability in two brown algae from the northern-central coast of Chile: effects of mesograzers and UV radiation

Macroalgae possess different defense mechanisms in response to herbivory. Some species produce anti-herbivore secondary metabolites, but production of these substances can be costly. Therefore, algae may produce defensive metabolites only in response to herbivory (inducible defense) or defend particular parts of the alga differentially (within-alga variation). In the present study, we examined whether two species of brown algae from the SE-Pacific show evidence of inducible chemical defense (non-polar compounds) or within-alga variation of defense, which we estimated in form of palatability of differently treated algae to amphipod grazers (with live algae and agar-based food containing non-polar algal extracts). In Glossophora kunthii (C. Agardh) J. Agardh, we observed an increase in palatability after algae were acclimated for 12 days without grazers. Subsequent addition of grazers for 12 days then resulted in a reduction of palatability indicating the existence of inducible defense. After removal of grazers for 12 days, these induced effects again disappeared. The reaction of G. kunthii was triggered even by the mere presence of grazers, which suggests that this alga can respond to waterborne cues by reducing palatability. Effects were only found for agar-based food containing non-polar extracts, but not for live algae, suggesting that some parts of the algae are undefended. Our second experiment on within-alga variation confirmed that only apical (growth region) and basal parts (near the holdfast region) of G. kunthii are defended against herbivores. For the second species, Macrocystis integrifolia Bory, the first experiment revealed no induction of defense, while the second experiment on within-alga variation showed that amphipods avoided basal parts and in particular stipes of M. integrifolia but only in live algae. Although both studied algal species differed substantially in their defensive strategies, their reaction was independent of the presence or absence of UV radiation. Thus, it appears that UV effects play only a minor role in anti-herbivore defense, which is in accordance with most previous studies

Ecología de invasiones marinas en Chile continental: ¿Qué sabemos y que nos falta por saber?

The Chilean coast has fewer reports of introduced species for other shores worldwide, which could correspond to a natural phenomenon generated by oceanographic conditions, or an artifact caused by lack of available information. We analyzed 71 papers indexed in Web of Science related with ecology of marine invasions in the Chilean coast, published between 1998-2014, and we determined the current state of the discipline in Chile, and identified the trends (e.g., temporal, spatial, taxonomic) of the investigation. Most of the papers studied species naturalization stage, and very few deal with invasive species. The number of papers per year increases linearly with time, suggesting a growing interest of the scientific community in the study of the ecology of marine invasions. The amount of available information (i.e., number of publications) is not homogeneous among administrative regions, and most papers have examined specific sectors within each region (usually near the regional capital). Regions with high maritime traffic (e.g., Valparaíso, Magallanes) have been scarcely studied. With the exception of Coquimbo and Los Lagos, researches by region have been performed on a few taxa. Hardly any studies cover large spatial scales, although several of them do perform monitoring programs on longer time scales (e.g., monthly, yearly). Our results suggest that the number of exotic species in Chile may be underestimated. Field observations, periodic updating of catalogs and use of molecular tools are proposed as measures to achieve a greater understanding of the issue at national level.La costa chilena presenta menos reportes de especies introducidas respecto a otras costas a nivel mundial, lo que podría corresponder a un fenómeno natural generado por condiciones oceanográficas, o bien a un artefacto producido por falta de información disponible. Mediante el análisis de 71 trabajos indexados en Web of Science, relacionados con ecología de invasiones marinas en la costa chilena, publicados entre 1998-2014, determinamos el estado actual de esta disciplina en Chile, e identificamos las tendencias de las investigaciones realizadas. La mayoría de las publicaciones se relacionan con especies en etapa de naturalización, y pocas con especies invasoras. El número de publicaciones por año incrementa linealmente, sugiriendo un creciente interés de la comunidad científica respecto al tema. La cantidad de información disponible (i.e., número de publicaciones) no es homogénea entre las regiones administrativas, y la mayoría de los trabajos son realizados sectores puntuales dentro de cada región (usualmente cercanos a la capital regional). Regiones con alto tráfico marítimo (e.g., Valparaíso, Magallanes) han sido muy poco estudiadas. A excepción de la región de Coquimbo y Los Lagos, los trabajos por región apuntan a unos pocos taxa. Muy pocos trabajos abarcan grandes escalas espaciales, aunque varios de ellos realizan experimentos a escalas de tiempo mayores (e.g., mensual, anual). Nuestros resultados permiten sugerir que el número de especies reportadas como introducidas en Chile podría estar subestimado. Observaciones en terreno, actualización periódica de catastros y utilización de herramientas moleculares, son propuestos como medidas para una mayor comprensión del tema a nivel nacional

Induction of defenses and within-alga variation of palatability in two brown algae from the northern-central coast of Chile: effects of mesograzers and UV radiation.

Abstract Macroalgae possess different defense mechanisms in response to herbivory. Some species produce anti-herbivore secondary metabolites, but production of these substances can be costly. Therefore, algae may produce defensive metabolites only in response to herbivory (inducible defense) or defend particular parts of the alga differentially (within-alga variation). In the present study, we examined whether two species of brown algae from the SE-Pacific show evidence of inducible chemical defense (non-polar compounds) or within-alga variation of defense, which we estimated in form of palatability of differently treated algae to amphipod grazers (with live algae and agar-based food containing non-polar algal extracts). In Glossophora kunthii (C. Agardh) J. Agardh, we observed an increase in palatability after algae were acclimated for 12 days without grazers. Subsequent addition of grazers for 12 days then resulted in a reduction of palatability indicating the existence of inducible defense. After removal of grazers for 12 days, these induced effects again disappeared. The reaction of G. kunthii was triggered even by the mere presence of grazers, which suggests that this alga can respond to waterborne cues by reducing palatability. Effects were only found for agar-based food containing non-polar extracts, but not for live algae, suggesting that some parts of the algae are undefended. Our second experiment on within-alga variation confirmed that only apical (growth region) and basal parts (near the holdfast region) of G. kunthii are defended against herbivores. For the second species, Macrocystis integrifolia Bory, the first experiment revealed no induction of defense, while the second experiment on within-alga variation showed that amphipods avoided basal parts and in particular stipes of M. integrifolia but only in live algae. Although both studied algal species differed substantially in their defensive strategies, their reaction was independent of the presence or absence of UV radiation. Thus, it appears that UV effects play only a minor role in anti-herbivore defense, which is in accordance with most previous studies.

Distribución geográfica y descripción de cuatro especies de cirripedios pelágicos a lo largo de la costa chilena del Pacífico sur este - una aproximación zoogeográfica

The majority of zoogeographic studies along the Chilean Pacific coast have focused on benthic organisms and oceanographic conditions are considered the main factors influencing their distributions. Herein we examined the geographic distribution of pelagic barnacles of the family Lepadidae collected from floating macroalgae at seven sampling areas between 23 and 50° S. Four species were encountered and they are briefly described herein. The most abundant northern species was Lepas anatifera, and it diminished in abundance towards the south (33° S). Moreover, this species was not found in waters with a sea surface temperature (SST) of less than ~18 ºC. Lepas australis, primarily a circumpolar West Wind Drift species, diminished in abundance towards the north (33° S). This species was restricted to waters of < 18 ºC SST. A third species, L. pectinata, was encountered throughout almost the entire study area, but it was most abundant between 29 and 33° S. The fourth species, Dosima fascicularis, was only found at two sampling areas, namely at 27° S and 33° S, and this is the first record of this species from the central coast of Chile. The distributional pattern of the pelagic barnacles found herein corresponds to the three main zoogeographic regions as revealed by the majority of previous studies based on littoral organisms: the northern Peru-Chilean Province, the southern Magellanic Province, and the central Chilean Transition Zone where the two provinces overlap. Even though the present study only considers four species of pelagic barnacles, the results support the hypotheses on the importance of oceanographic conditions (in particular SST) in determining the zoogeographic patterns along the south east Pacific coast of Chile

Early Developmental Stages of Crustacean Decapods Associated with Floating Seaweed in Fiord and Channels from Southern Chile

Durante el crucero "CIMAR 9 Fiordos" realizado en agosto y noviembre de 2003 en los fiordos y canales de la región de Aysén, Chile, se cuantificó la abundancia de macroalgas flotando a la deriva (MFD) y se identificó los estados tempranos de desarrollo de crustáceos decápodos (megalopas y juveniles, ETD) asociados a ellas. Las macroalgas Macrocystis spp. y Durvillaea antarctica fueron las más abundantes. Para ambos meses monitoreados se registraron las mayores abundancias de MFD en la zona norte del área de estudio y en el sector sur del canal Moraleda. Las abundancias de macroalgas fueron sustancialmente más altas en primavera (noviembre) que en invierno (agosto). Del mismo modo, sólo en primavera se encontró ETD asociados a estas macroalgas, pero en abundancias relativamente bajas (máximo de 5 ind. por muestra). Las especies de crustáceos decápodos encontradas en MFD son especies principalmente intermareales. En un estudio sobre MFD, realizado en la misma localidad y durante primavera de 2002 (CIMAR 8 Fiordos), se encontró mayores abundancias de ETD asociados que en el presente estudio. Se concluye que en la área de estudio hay un suplemento relativamente consistente y alto de MFD, pero existe elevada variabilidad inter e intra-anual de la presencia de ETD en estas macroalgas. Por lo tanto, se sugiere examinar con mayor detalle esta asociación para determinar la importancia de MFD en el proceso de reclutamiento de especies de crustáceos decápodos

Estados Tempranos de Desarrollo de Crustáceos Decápodos Asociados a Macroalgas Flotando a la Deriva en Fiordos y Canales del Sur de Chile

Durante el crucero "CIMAR 9 Fiordos" realizado en agosto y noviembre de 2003 en los fiordos y canales de la región de Aysén, Chile, se cuantificó la abundancia de macroalgas flotando a la deriva (MFD) y se identificó los estados tempranos de desarrollo de crustáceos decápodos (megalopas y juveniles, ETD) asociados a ellas. Las macroalgas Macrocystis spp. y Durvillaea antarctica fueron las más abundantes. Para ambos meses monitoreados se registraron las mayores abundancias de MFD en la zona norte del área de estudio y en el sector sur del canal Moraleda. Las abundancias de macroalgas fueron sustancialmente más altas en primavera (noviembre) que en invierno (agosto). Del mismo modo, sólo en primavera se encontró ETD asociados a estas macroalgas, pero en abundancias relativamente bajas (máximo de 5 ind. por muestra). Las especies de crustáceos decápodos encontradas en MFD son especies principalmente intermareales. En un estudio sobre MFD, realizado en la misma localidad y durante primavera de 2002 (CIMAR 8 Fiordos), se encontró mayores abundancias de ETD asociados que en el presente estudio. Se concluye que en la área de estudio hay un suplemento relativamente consistente y alto de MFD, pero existe elevada variabilidad inter e intra-anual de la presencia de ETD en estas macroalgas. Por lo tanto, se sugiere examinar con mayor detalle esta asociación para determinar la importancia de MFD en el proceso de reclutamiento de especies de crustáceos decápodos

Dictyota falklandica sp. nov. (Dictyotales, Phaeophyceae) from the Falkland Islands and southernmost South America

ACKNOWLEDGEMENTS Special thanks to Paul Brickle (South Atlantic Environmental Research Institute) for hosting our expedition. FUNDING We thank the Shackleton Scholarship Fund (for travel grants to FCK and AFP to the Falkland Islands), the UK Natural Environment Research Council (program Oceans 2025 – WP 4.5 and grant NE/D521522/1), and the TOTAL Foundation (Project “Diversity of brown algae in the Eastern Mediterranean”). This work also received support from the Marine Alliance for Science and Technology for Scotland pooling initiative. MASTS is funded by the Scottish Funding Council (grant reference HR09011) and contributing institutions. ECM acknowledges support by the Chilean Millennium Initiative (NC120030) grant. This work makes use of resources and facilities provided by Ghent University as part of the Belgian contribution to EMBRC-ERIC (FWO GOH3817N).Peer reviewedPublisher PD

Geographic distribution and description of four pelagic barnacles along the south east Pacific coast of Chile - a zoogeographical approximation

The majority of zoogeographic studies along the Chilean Pacific coast have focused on benthic organisms and oceanographic conditions are considered the main factors influencing their distributions. Herein we examined the geographic distribution of pelagic barnacles of the family Lepadidae collected from floating macroalgae at seven sampling areas between 23 and 50° S. Four species were encountered and they are briefly described herein. The most abundant northern species was Lepas anatifera, and it diminished in abundance towards the south (33° S). Moreover, this species was not found in waters with a sea surface temperature (SST) of less than ~18 ºC. Lepas australis, primarily a circumpolar West Wind Drift species, diminished in abundance towards the north (33° S). This species was restricted to waters of < 18 ºC SST. A third species, L. pectinata, was encountered throughout almost the entire study area, but it was most abundant between 29 and 33° S. The fourth species, Dosima fascicularis, was only found at two sampling areas, namely at 27° S and 33° S, and this is the first record of this species from the central coast of Chile. The distributional pattern of the pelagic barnacles found herein corresponds to the three main zoogeographic regions as revealed by the majority of previous studies based on littoral organisms: the northern Peru-Chilean Province, the southern Magellanic Province, and the central Chilean Transition Zone where the two provinces overlap. Even though the present study only considers four species of pelagic barnacles, the results support the hypotheses on the importance of oceanographic conditions (in particular SST) in determining the zoogeographic patterns along the south east Pacific coast of Chile

Chloroplast genomes as a tool to resolve red algal phylogenies: a case study in the Nemaliales

Obtaining strongly supported phylogenies that permit confident taxonomic and evolutionary interpretations has been a challenge in algal biology. High-throughput sequencing has improved the capacity to generate data and yields more informative datasets. We sequenced and analysed the chloroplast genomes of 22 species of the order Nemaliales as a case study in the use of phylogenomics as an approach to achieve well-supported phylogenies of red algae.Australian Research Council/[FT110100585]/ARC/AustraliaAustralian Biological Resources Study/[RFL213-08]/ABRS/AustraliaMillennium Scientific Initiative/[NC120030]/MSI/Nueva JerseyUniversity of Melbourne///AustraliaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Ciencias del Mar y Limnología (CIMAR

Ecología de invasiones marinas en Chile continental: ¿Qué sabemos y que nos falta por saber?

The Chilean coast has fewer reports of introduced species for other shores worldwide, which could correspond to a natural phenomenon generated by oceanographic conditions, or an artifact caused by lack of available information. We analyzed 71 papers indexed in Web of Science related with ecology of marine invasions in the Chilean coast, published between 1998-2014, and we determined the current state of the discipline in Chile, and identified the trends (e.g., temporal, spatial, taxonomic) of the investigation. Most of the papers studied species naturalization stage, and very few deal with invasive species. The number of papers per year increases linearly with time, suggesting a growing interest of the scientific community in the study of the ecology of marine invasions. The amount of available information (i.e., number of publications) is not homogeneous among administrative regions, and most papers have examined specific sectors within each region (usually near the regional capital). Regions with high maritime traffic (e.g., Valparaíso, Magallanes) have been scarcely studied. With the exception of Coquimbo and Los Lagos, researches by region have been performed on a few taxa. Hardly any studies cover large spatial scales, although several of them do perform monitoring programs on longer time scales (e.g., monthly, yearly). Our results suggest that the number of exotic species in Chile may be underestimated. Field observations, periodic updating of catalogs and use of molecular tools are proposed as measures to achieve a greater understanding of the issue at national level.La costa chilena presenta menos reportes de especies introducidas respecto a otras costas a nivel mundial, lo que podría corresponder a un fenómeno natural generado por condiciones oceanográficas, o bien a un artefacto producido por falta de información disponible. Mediante el análisis de 71 trabajos indexados en Web of Science, relacionados con ecología de invasiones marinas en la costa chilena, publicados entre 1998-2014, determinamos el estado actual de esta disciplina en Chile, e identificamos las tendencias de las investigaciones realizadas. La mayoría de las publicaciones se relacionan con especies en etapa de naturalización, y pocas con especies invasoras. El número de publicaciones por año incrementa linealmente, sugiriendo un creciente interés de la comunidad científica respecto al tema. La cantidad de información disponible (i.e., número de publicaciones) no es homogénea entre las regiones administrativas, y la mayoría de los trabajos son realizados sectores puntuales dentro de cada región (usualmente cercanos a la capital regional). Regiones con alto tráfico marítimo (e.g., Valparaíso, Magallanes) han sido muy poco estudiadas. A excepción de la región de Coquimbo y Los Lagos, los trabajos por región apuntan a unos pocos taxa. Muy pocos trabajos abarcan grandes escalas espaciales, aunque varios de ellos realizan experimentos a escalas de tiempo mayores (e.g., mensual, anual). Nuestros resultados permiten sugerir que el número de especies reportadas como introducidas en Chile podría estar subestimado. Observaciones en terreno, actualización periódica de catastros y utilización de herramientas moleculares, son propuestos como medidas para una mayor comprensión del tema a nivel nacional