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Mariculture of edible Porphyra/Pyropia species, which are cosmopolitan red foliose algae, represent an important source of income for the pharmaceutical and food industries. In Chile, the most common alga of this complex is Pyropia orbicularis (Bangiales, Rhodophyta). Here we report 6 microsatellite markers obtained from P. orbicularis through a genomic library from 10 individuals of the gametophytic phase by next generation (Illumina) sequencing. Polymorphism analyses were done from 10 individuals of the conchocelis phase, revealing an allelic diversity ranging from three to six alleles per locus, and observed heterozygosity (HO) and expected heterozygosity (HE) ranging from 0.200 to 0.995, and 0.250 to 0.610, respectively. A large proportion of genetic variance (61%) in P. orbicularis was among individuals within population, and 39% genetic variance was among populations. Nonetheless, these results should be interpreted with caution; further research using larger sample sizes is required. These polymorphic markers could be useful in future studies on population genetic structure, for conservation and applied purposes.

In this study we report for the first time the appearance of an endophytic filamentous red alga, living associated with the edible red seaweed Chondracanthus chamissoi. Molecular identification, growth, and reproduction of this endophyte are described under different conditions: photoperiod (8:16, 12:12, and 16:08 L:D), temperature (10 and 15 °C), and photon flux density (40 and 20 μmol photons m−2 s−1). Filaments of this endophyte were isolated and cultured, and the growth was recorded according to the number of branches and its reproduction, by quantifying the emergence of monosporangia. By sequencing the COI gene and through phylogeny reconstruction using maximum likelihood, we determined that this endophyte corresponded to Colaconema daviesii. The highest growth was recorded under the treatment 16:08 (L:D), 10 °C, and 20 μmol photons m−2 s−1, reaching up to 100 branches after 18 days. On the other hand, over 80% of filaments with monosporangia were observed at 12:12 (L:D), 10 °C, and 20 μmol photons m−2 s−1. This is the first record of C. daviesii on the South-eastern Pacific as an endophyte on thalli of C. chamissoi. The results of the in vitro cultures showed that once C. daviesii is isolated, the filaments are able to grow and reproduce independently of C. chamissoi. This suggests that there may not be a strict relationship between both algae and reveals the possibility of finding C. daviesii living without a host or associated with other species.

Members of the genus Chondracanthus (Rhodophyta, Gigartinales) inhabit the shores of both hemispheres and have been used for decades in some countries as raw material for carrageenan extraction and in some cases destined for human consumption. This has created potential business opportunities, which has drawn the attention of scientists and producers and increased the number of scientific and applied research studies in the last few years. The broad morphological variation of Chondracanthus species makes necessary the use of molecular tools for species delimitation, which has led to the re-grouping and geographic re-distribution of some entities. The present study is a review of the available literature on members of the genus Chondracanthus, with the exception of Chondracanthus teedei, regarding their identity, distribution, ecology, life history, population structure, chemical traits, handling, and culture.

International audience; A recent molecular taxonomic study along the Chilean coast (18° S–53° S) described 18 candidate species of bladed Bangiales of which only two were formally described. Few studies focused on local genetic and morphological diversity of bladed Bangiales and attempted to determine their intertidal distribution in contrasting habitats, and none were performed in Chile. To delimit intertidal distributions of genetic species, 66 samples of bladed Bangiales were collected at Maitencillo (32° S) in four zones: a rocky platform, a rocky wall, and two boulders zones surrounded by sandy and rocky bottoms, respectively. These samples were identified based on sequences of the mitochondrial COI and chloroplast rbcL markers. We also collected 87 specimens for morphological characterization of the most common species, rapidly assessing their putative species identity using newly developed species‐diagnostic (PCR‐RFLP) markers. Eight microscopic and two macroscopic morphological traits were measured. We described and named three of four species that predominate in Maitencillo (including Pyropia orbicularis): Pyropia variabilis Zapata, Meynard, Ramírez, Contreras‐Porcia, sp. nov., Porphyra luchea Meynard, Ramírez, Contreras‐Porcia sp. nov., and Porphyra longissima Meynard, Ramírez, Contreras‐Porcia, sp. nov. With the exception of Po. longissima restricted to boulders surrounded by sandy bottom, and a morphotype of Py. variabilis restricted to rocky walls, the other species/morphotypes have overlapping intertidal distributions. Except for Po. longissima, which is clearly differentiated morphologically (longest and thinnest blades), we conclude that morphology is not sufficient to differentiate bladed Bangiales. Our findings underscore the importance of refining our knowledge of intrinsic and environmental determinants on the distribution of bladed Bangiales.

espanolResumen: El registro de la diversidad de algas permite reconocer especies que podrian generar informacion base para medidas de manejo, proteccion de los ambientes y presentar nuevas oportunidades de uso. En este contexto, el objetivo del presente trabajo fue determinar la riqueza, cobertura y composicion del ensamble de especies de macroalgas en la zona intermareal de Maitencillo, Valparaiso, Chile, durante 3 anos de monitoreo (2013-2015). Un total de 29 especies fueron registradas, donde 23 de ellas pertenecen a Rhodophyta, 3 a Ochrophyta; clase Phaeophyceae, y 3 a Chlorophyta. La riqueza de especies presento una alta variacion espacio-temporal en el area de estudio, donde las zonas del intermareal y las estaciones del ano presentaron un efecto significativo, explicando un 61 y 31% de su variabilidad, respectivamente. La mayor riqueza especifica se registro en las zonas media y baja (14 especies) durante primavera, y en la zona baja del intermareal (14) durante verano. Los menores valores fueron encontrados en la zona media (2) durante otono. Las zonas del intermareal demostraron ser la variable de mayor importancia a nivel de la comparacion del ensamble de algas, explicando el 53% de la variacion, mientras que la estacionalidad explico el 18% de esta. La mayor cobertura fue registrada en la zona media durante primavera, con predominio de Mazzaella laminarioides y Ulva spp. En la estacion de otono se obtuvo la menor cobertura debido a los procesos de acrecion de arena. En paredones dominaron especies del complejo Pyropia. Los resultados indicaron un claro patron de distribucion vertical y variacion estacional en el ensamble de macroalgas, destacando una mayor presencia de especies de Rhodophyta. La descripcion de la flora bentonica obtenida en este trabajo actualiza la diversidad de algas representativa de la Region de Valparaiso, Chile. EnglishAbstract: Records on the diversity of algae serve as a foundation for establishing management and environmental protection programs, as well as for determining new commercial uses of algae. With this context in mind, the goal of the present study was to determine the richness, coverage, and composition of the macroalgae assemblage in the intertidal zone of Maitencillo, Valparaiso, Chile over the course of 3 years (2013-2015). A total of 29 species were recorded from three phyla - 23 Rhodophyta; 3 Ochrophyta, of the Phaeophyceae class; and 3 Chlorophyta. Species richness presented high spatial and temporal variations, with these variations most significantly explained by intertidal zone (61%) and the seasons (31%). The highest levels of specific richness were recorded in the mid and lower intertidal zones (14 species) in spring, as well as in the lower intertidal zone (14 species) during summer. The lowest values of specific richness were recorded for the mid intertidal zone (2 species) during fall. The distinct levels of the intertidal zone also notably impacted algae assemblage, explaining 53% of variation while the seasons explained 18% of variation. The greatest coverage was recorded in the mid intertidal zone during spring, with a predominance of Mazzaella laminarioides and Ulva spp. complex. In turn, the lowest coverage was found in fall, linked with processes of sand accretion. In rocky walls, the Pyropia complex dominated. Results indicate a marked pattern of vertical and seasonal distribution in the macroalgae assemblage, as well as notably high presence of Rhodophyta species. This benthic flora description serves to update information on the diversity of representative algal species from Valparaiso Region of Chile.

In the present study we introduce the development and implementation of a new technology for improving the seeding in the spore-based cultures on red algae (excluding Porphyra), using a spore re-suspending technology (SRT). Such technology has two operation differences with the current methods: (i) it allows the use of vertically placed frames, and (ii) resuspends the spores not yet settled from the bottom of the tanks. Using as model the carrageenophyte species Mazzaella laminarioides, the SRT was compared beside a conventional method using horizontally placed frames at the bottom of the tanks as control, considering settlement, germination, growth, efficiency and productivity. The results showed that both the vertical position of the frames and the spore resuspension did not have a negative effect on the spore settlement, germination and growth, being as effective and productive as the conventional methods. In addition, the design of the SRT allows to inoculate more substrate without increasing the initial reproductive thalli mass. Therefore, this technology opens new possibilities for the spore-based cultures of red algae, and could be adapted to different species, dimensions and volumes.

This study analyzed the economic feasibility of offshore commercial cultivation of Macrocystis pyrifera in northern Chile. To achieve this objective, a continuous-time model including biological, technological, and economic aspects was developed. To implement this model, the biomass growth until marketable size is reached was estimated for three periods of the year. A periodic system of cultivation and harvesting is described, and the main investments, operation costs, remunerations, and operational costs of cultivation and harvesting are defined. The results of the baseline model show that cultivation is not profitable in the long term considering the selling price and the harvest yield. Additionally, at baseline, the revenue is unable to cover the investment costs or the operation costs. However, in a scenario in which productivity is 211 % higher than the base harvest and prices are 25 % higher, cultivation becomes profitable, with positive net present values (NPV) after 14 years. Despite the aforementioned considerations, the opportunity for generating greater value from this type of cultivation is discussed, taking into account its characteristics as units that provide ecosystem services, which is a feature that is starting to be discussed in relation to marine environments.

International audience; A new species of bladed Bangiales, Pyropia orbicularis sp. nov., has been described for the first time from the central coast of Chile based on morphology and molecular analyses. The new species was incorrectly known previously as Porphyra columbina (now Pyropia columbina), and it can be distinguished from other species of Pyropia through a range of morphological characteristics, including the shape, texture and colour of the thallus, and the arrangement of the reproductive structures on the foliose thalli. Molecular phylogenies based on both the mitochondrial COI and plastid rbcL gene regions enable this species to be distinguished from other species within Pyropia. P. orbicularis sp. nov. belongs to a well-supported clade of Pyropia from the southern oceans that include specimens from the South Pacific (North, South, Chatham, Stewart, Auckland, and Campbell Island, New Zealand, New South Wales, and Macquarie Island, Australia) including P. columbina and P. plicata. Within this clade, the highest sequence identity was observed between Pyropia orbicularis sp. nov. and Pyropia sp. FIC from the Falkland Islands.