Abstract Studies of marine and estuarine red algae (Rhodophyta) are in the early stages in the littoral of the Sian Ka’an Biosphere Reserve, Mexico. The inventory of these organisms was made based on samples obtained from ten sampling during 2009 to 2015 in 22 localities, eight of them in marine and fourteen in estuarine environments. We found 182 species and subspecific taxa of Rhodophyta. The Rhodomelaceae family was the best represented with 65 taxa, followed by Ceramiaceae 13 and Delesseriaceae 12. Of the 182 taxa, 25 are new records Sian Ka’an Biosphere Reserve with Harveylithon rupestre, Spongites fruticulosus, Acrochaetium barbadense, Dasya harveyi, Chondria pumila, Spermothamnion repens, Metapeyssonnelia milleporoides and M. tangerina being new records for the Mexican Caribbean. Of the 182 species, 119 of them are epiphytes, most of them, 54, grew exclusively on other macroalgae, 29 on mangrove roots and 8 on Thalassia leaves. The floristic list is accompanied by data on seasonality, reproduction, habitat, and environment. Species diversity was compared between the winter rains, dry and rainy seasons during the period study. The Rhodophyta of the Sian Ka’an Biosphere Reserve is tropical, and the greatest diversity was found in the marine environment with 83 taxa and during the winter rains with 132. (Rhodophyta Kaan Ka an Mexico 200 201 2 localities environments 18 6 1 12 rupestre fruticulosus barbadense harveyi pumila repens M Caribbean 11 epiphytes 54 macroalgae leaves seasonality reproduction habitat study tropical 132 20 5

Resumo: Os estudos de algas vermelhas marinhas e estuarinas (Rhodophyta) estão em fase inicial no litoral da Reserva da Biosfera de Sian Ka’na, México. O inventário desses organismos foi feito com base em amostras obtidas em oito amostragens no período do 2009 a 2015 em 22 localidades, sendo oito em ambientes marinhos e quatorze em ambientes estuarinos. Neste levantamento, foram identificadas um total de 182 espécies e táxons subespecíficos de Rhodophyta. A família Rhodomelaceae foi a mais representativa com 65 táxons, seguida por Ceramiaceae com 13 e Delesseriaceae com 12. Dos 182 táxons, 25 são referidos pela primeira vez para a Reserva da Biosfera Sian Ka’an, sendo Harveylithon rupestre, Spongites fruticulosus, Acrochaetium barbadense, Dasya harveyi, Chondria pumila, Spermothamnion repens, Metapeyssonnelia milleporoides e M. tangerina também novos registros para o Caribe mexicano. Das 182 espécies, 119 são epífitas, sendo a maioria, 54, aderidas exclusivamente em outras macroalgas, 29 em raízes de mangue e 8 em folhas de Thalassia. A lista florística apresentada é acompanhada de dados sobre sazonalidade, reprodução, habitat e ambiente. A diversidade de espécies foi comparada entre as temporadas de chuvas de inverno, seca e chuvas de verão durante o período estudado. Rhodophyta da Reserva da Biosfera Sian Ka’an săo tropicais, e a diversidade mais representativa foi encontrada no ambiente marinho com 83 táxons e durante as chuvas de inverno com um total de 132 táxons. Resumo (Rhodophyta Kana, Kana Ka na, na Ka’na México 200 201 2 localidades estuarinos levantamento 18 6 1 12 Kaan, Kaan an, an rupestre fruticulosus barbadense harveyi pumila repens M mexicano 11 epífitas maioria 54 macroalgas Thalassia sazonalidade reprodução estudado tropicais 20 5

Abstract Seaweeds have been used by several industrial sectors, such as the food, feed, pharmaceutical and biofuel industries. Thereby, techniques to increase seaweed production are needed due to the rising global demand for biomass. Thus, we investigated the effects of different weekly nutrient pulses [N and P at ratios of 10:1 (T1), 20:2 (T2), and 50:5 (T3)] on the biomass, relative growth rate (RGR) and biochemical composition of Gracilaria domingensis. A control without nutrient pulses was also established. The highest biomass values were recorded in T1. The RGR was more constant in T1 and T2 than in T3 throughout the cultivation. Significant decreases in RGR were observed in the control compared to the other treatments, and null RGR was recorded in T3. Regarding the seaweed biochemical composition, the lowest carbohydrate and lipid content and the highest ash content were recorded in T1. In our study, G. domingensis showed nutritional values similar or even superior to those reported for other seaweeds used as food. We concluded that T1 is the most suitable treatment to increase G. domingensis production. In addition to being the least expensive treatment, in T1, G. domingensis exhibited the highest biomass values, constant RGR, and nutritional composition suitable for human consumption. sectors food feed industries Thereby Thus N 101 10 1 10: T , (T1) 202 20 2 20: T2, (T2) 505 50 5 50: (T3) (RGR established cultivation treatments study G consumption (T1 (T2 (T3 (T

ABSTRACT Along the line that health-beneficial foods must also be accompanied by sustainable agricultural practices, the red alga Lithothamnium sp. (Rhodophyta), frequently used for animal and human nutrition, it was shown that it could be a biofertilizer, regarding their bioactive humic acid content, released by micronization. Also, onions present well-known benefits to health and are among the main vegetable crops grown worldwide. Thus, the objective this work was to evaluate the effects of foliar sprays with micronized Lithothamniun sp. on yield, mineral nutrients, flavonoids, phenolic content, and antioxidant activity before and after storage of bulbs of two organically grown onion cultivars. The yield, mineral content, antioxidant activity, and phenolic and flavonoid content in onion bulbs were improved through sprays, highlighting the dose of 1.5 g L-1 of Lithothamnium sp. in solution. Genotype interactions and storage effects were observed. The benefits with the use of Lithothamnium sp. as biofertilizer were towards the biofortification of organically grown onions by improving mineral nutrient acquisition as it was followed by upgrading antioxidant capacity. healthbeneficial beneficial practices sp Rhodophyta, Rhodophyta , (Rhodophyta) nutrition micronization Also wellknown well known worldwide Thus yield nutrients flavonoids cultivars 15 1 5 1. L1 L L- solution observed capacity (Rhodophyta

Abstract: The coastal waters of Ecuador have emerged as a favorable environment for the growth and development of several species of edible macroalgae or seaweeds. In this study, fatty acid profiles, total soluble polyphenol content, and antioxidant capacity of seven species of macroalgae (four red algae, two brown algae and one green algae) collected from Salinas Bay, Santa Elena Province, Ecuador, were evaluated. Saturated fatty acids C14:0, C15:0, C16:0 and C18:0 were found in almost all organisms, from which palmitic acid showed the highest proportion (10.7-37.1%). Green and brown seaweeds exhibited a major content of unsaturated fatty acids. Monounsaturated fatty acid composition was represented by several isomers of C16:1 and C18:1, mainly palmitoleic (3.0-6.6%) and oleic (0.8-11.1%) acids. Polyunsaturated fatty acid composition ranged from 5.47 to 26.61%, with ratios of total n-6/n-3 acids lower than 3.3. Linoleic (C18:2, n-6, 1.16-7.73%) and eicosapentaenoic (C22:5, EPA, n-3, 1.44-5.92%) acids were found in the majority of the seaweeds. The total polyphenol content of the seaweeds was determined by the Folin-Ciocalteu method (765 nm), and ranged from 147.28 to 1,062.20 mg equivalents of gallic acid (GAE) per 100 g of dry seaweed. The antioxidant capacity was determined by the Trolox equivalent antioxidant capacity (517 nm). Only Acanthophora spicifera, Spatoglossum schroederi, and Ulva lactuca showed good radical-scavenging (14.18-3,379.47 mg Trolox equivalents (TE) per 100 g of dry seaweed). The results confirm the potential use of macroalgae in the study area as an important source of nutritional compounds, especially brown and green algae, which could be a recommended food supplement even in the treatment of some diseases.

ABSTRACT The growth in the number of molecular sequences produced in recent years has provided valuable contributions to the knowledge diversity of red algae (Rhodophyta) in Brazil. However, many works indicate that there is still much to be studied. Here, we highlight the importance of compiling all these data to evidence possible taxonomic and geographic knowledge gaps in red algae through molecular data. So, this study presents a scientometric analysis of the molecular studies carried out on red algae in Brazil, based on the analysis of DNA sequences available in the public database GenBank. Our results demonstrated an increase in published papers from 1994 to 2020, corresponding to 165 studies analyzed. A huge disparity in the production of knowledge was observed, with the southeastern region concentrating the researchers responsible for most of the published studies, with emphasis on those in the University of São Paulo (USP). Bahia and São Paulo states stand out with the highest observed taxonomic richness, respectively. We also could identify the taxonomic groups with more molecular data generated, the sequence number deposited per institution since 1994, the main markers used, the regions that require a greater collection effort, and where the researchers who study red algae in the country are.

Abstract: Background and Aims: The reefs of the Parque Nacional Arrecifes de Cozumel constitute one of the main reef formations in Mexico. However, up to date phycofloristic studies that allow detecting changes in the phycofloristic composition or its affinity for some substrates are practically non-existent. Our aim was to determine the taxonomic composition of marine macroalgae present in the Parque Nacional Arrecifes de Cozumel, as well as realize their morphological descriptions and an analysis of their affinity with the substrate they colonize. Methods: The sampling was carried out in October and November 2018 by autonomous diving in 14 reefs of the Parque Nacional Arrecifes de Cozumel. Morphological observations were made using optical and stereoscopic microscopes. The taxonomic determination was made using specialized literature. Key results: Fourty-two taxa were determined: five Ochrophyta, 12 Rhodophyta and 25 Chlorophyta. The best-represented family for Ochrophyta was Dictyotaceae; for Rhodophyta, Ceramiaceae and Rhodomelaceae; and for Chlorophyta, Halimedaceae. New records for the Parque Nacional Arrecifes de Cozumel are described, including Lobophora guadeloupensis as a new record for Mexico. Additionally, four different substrates for the algae were identified: psammophytic (33%), epilithic (32%), epizoic (19%) and epiphytic (16%). The most diverse reefs were La Francesa (LF) and Santa Rosa (SR), whereas the least diverse were Chankanaab (CK) and Tormentos (TM). Conclusions: Although many of the previous records in the area were confirmed in the present study, the presence of 18 new records revealed, on the one hand, the lack of constant monitoring of the algal richness of the region, and on the other hand, the need for morphological descriptions or photographic references that allow contrasting the previous records with the current ones. Given the importance of the Parque Nacional Arrecifes de Cozumel, our results, in addition to offering updated information, represent a starting point for studies in conservation biology.

Resumen: Antecedentes y Objetivos: Los arrecifes del Parque Nacional Arrecifes de Cozumel constituyen una de las principales formaciones arrecifales de México. Sin embargo, actualmente, son prácticamente inexistentes los estudios ficoflorísticos que permiten detectar cambios en la composición ficoflorística o su afinidad por algún sustrato. Por lo tanto, nuestro objetivo fue determinar la composición taxonómica de macroalgas marinas presentes en el Parque Nacional Arrecifes de Cozumel, así como realizar sus descripciones morfológicas y análisis de afinidad con el sustrato que colonizan. Métodos: Los muestreos se realizaron en octubre y noviembre de 2018 en 14 arrecifes del Parque Nacional Arrecifes de Cozumel, mediante buceo autónomo. Se realizaron observaciones morfo-anatómicas utilizando tanto microscopios ópticos como estereoscópicos. La determinación taxonómica se realizó a partir de literatura especializada. Resultados clave: Se determinaron 42 taxa: cinco Ochrophyta, 12 Rhodophyta y 25 Chlorophyta. La familia mejor representada para Ochrophyta fue Dictyotaceae; para Rhodophyta, Ceramiaceae y Rhodomelaceae; y para Chlorophyta, Halimedaceae. Se describen nuevos registros para el Parque Nacional Arrecifes de Cozumel incluyendo a Lobophora guadeloupensis como nuevo registro para México. Adicionalmente, se identificaron cuatro diferentes sustratos para las algas: psamofítico (33%), epilítico (32%), epizoico (19%) y epífito (16%). Los arrecifes más diversos fueron La Francesa (LF) y Santa Rosa (SR), y los menos diversos fueron Chankanaab (CK) y Tormentos (TM). Conclusiones: Aunque muchos de los registros previos en el área fueron confirmados en el presente estudio, la presencia de 18 nuevos registros reveló, por un lado, la falta de monitoreos constantes de la riqueza algal de la región, y, por otro lado, la necesidad de contar con descripciones morfológicas o referencias fotográficas que permitan contrastar los registros previos con los actuales. Dada la importancia del Parque Nacional Arrecifes de Cozumel, nuestros resultados, además de ofrecer información actualizada, representan un punto de partida para estudios en biología de la conservación.

Abstract: Background and Aims: Since the publication of the book on Cuban marine macroalgae in 2015, new records have been found and taxonomic changes have been published. Therefore, the objective of this publication is to present a fifth updated systematic review, that includes Ochrophyta (Class Phaeophyceae), Rhodophyta and Chlorophyta. Methods: These results were recorded from information available in scientific papers, bachelor, master and doctoral theses, as well as scientific-technical reports from recognized specialists, considering those not included in the last review or that were published after 2015. The taxa were systematically ordered, the names and synonymy were reviewed according to Algaebase and the most recent scientific literature. Species were arranged alphabetically within each family. The distribution of each taxon was resumed for nine Ecological Districts (zones) of the Cuban shelf. Key results: An updated floristic list with 569 species, one subspecies, 25 varieties, and 21 forms is presented. Thirty-seven species are added to the previous review of which seven are new records for Cuba: Hydrolithon boergesenii, Neogoniolithon mamillare, N. propinquum, N. rhizophorae, Lithothamnion crispatum, Liagoropsis schrammii, and Peyssonnelia rubra. The distribution of these taxa in the nine zones of the Cuban shelf is provided. Conclusions: The zones showing more species have had a greater sampling effort or were predominantly rocky reef bottoms. However, macroalgae have not been inventoried in detail in the intertidal zone, bays, and coastal lagoons. Zones with fewer species coincide in having a narrower shelf where rocky substrates dominate, although macroalgae have not been inventoried in the intertidal zone, bays, and coastal lagoons.

Resumen: Antecedentes y Objetivos: Desde la publicación del libro sobre las macroalgas marinas de Cuba en 2015 se han publicado nuevos registros y cambios taxonómicos. Por lo anterior, el objetivo del presente trabajo fue presentar una quinta revisión sistemática actualizada, que incluye Ochrophyta (Clase Phaeophyceae), Rhodophyta y Chlorophyta. Métodos: Se recopiló la información disponible en publicaciones científicas, tesis de licenciatura, maestría y doctorado, e informes científico-técnicos de especialistas reconocidos, considerando aquellas que no fueron comprendidas en la revisión anterior o que fueron publicadas después de 2015. Los taxones encontrados fueron ordenados sistemáticamente, los nombres actualizados y la sinonimia revisada según AlgaeBase y la literatura más reciente. Las especies se ordenaron alfabéticamente dentro de cada familia. La distribución de cada taxón se resumió para nueve zonas consideradas como Distritos Ecológicos (zonas) de la plataforma cubana. Resultados claves: Se presenta un listado florístico actualizado con 569 especies, una subespecie, 25 variedades y 21 formas. Se añaden a la anterior revisión 38 especies, de las cuales siete son nuevos registros para Cuba: Hydrolithon boergesenii, Neogoniolithon mamillare, N. propinquum, N. rhizophorae, Lithothamnion crispatum, Liagoropsis schrammii y Peyssonnelia rubra. Se da la distribución de cada uno de estos taxones en las nueve zonas de la plataforma cubana. Conclusiones: Las zonas que presentaron más especies son aquellas que han tenido un mayor esfuerzo de muestreo o donde predominan los fondos rocosos arrecifales, aunque no se han inventariado detalladamente las macroalgas en la zona mesolitoral, bahías y lagunas costeras.

Resumen: Antecedentes y Objetivos: Los sistemas estuarinos veracruzanos cubren 1166 km2 correspondientes a 14 lagunas costeras que constituyen uno de los ambientes acuáticos con mayor diversidad y productividad. Estos son ambientes críticos para especies económicamente importantes, como las macroalgas, que dependen de ellos para su reproducción, alimentación, establecimiento y refugio. Aunque lo anterior los hace candidatos ideales para estudios de biología de la conservación, solo hay dos contribuciones previas a 1995 sobre ficología estuarina. Por tanto, el objetivo de este trabajo fue elaborar un listado sistemático actualizado de las macroalgas estuarinas de Veracruz, junto con un análisis gráfico, que contribuya al conocimiento del grupo y sirva como referencia para posteriores investigaciones biogeográficas, ecológicas o de conservación. Métodos: Se revisó la literatura ficológica publicada de 1963 a septiembre de 2022, así como la base de datos del herbario UAMIZ, para complementar y actualizar los registros. Para la determinación taxonómica de los ejemplares se hizo un estudio de morfología externa. La sinonimia y estatus nomenclatural fueron revisados en AlgaeBase. A partir de los registros obtenidos se realizó un análisis gráfico. Resultados clave: Se presenta una lista actualizada con 113 especies de macroalgas estuarinas: 62 Rhodophyta, 26 Phaeophyceae, Ochrophyta y 25 Chlorophyta, distribuidas en 24 órdenes, 38 familias y 68 géneros. Conclusiones: De acuerdo con lo observado, son evidentes los escasos o nulos estudios ficológicos en ambientes estuarinos veracruzanos, lo que origina un vacío en el contexto de la diversidad de macroalgas estuarinas. Este listado, además de ser una contribución actualizada para Veracruz, es un punto de partida para emprender futuros análisis que ayuden a establecer áreas de importancia biológica en estos ambientes, con el fin de maximizar la diversidad. Además, es evidente la necesidad de un monitoreo ficofloristico constante en los estuarios.

Abstract: Background and Aims: The Veracruz estuarine systems cover 1166 km2, corresponding to 14 coastal lagoons, that constitute one of the aquatic environments with the greatest diversity and productivity. They are critical environments for economically important species, such as macroalgae, which depend on them for their reproduction, feeding, establishment and refuge. Although the above makes them ideal candidates for conservation biology studies, there are only two contributions prior to 1995 on estuarine phycology. Therefore, the objective of this work was to elaborate an updated systematic list of the estuarine macroalgae of Veracruz, together with a graphical analysis, which contributes to the knowledge of the group and serves as a reference for subsequent biogeographical, ecological or conservation research. Methods: Phycological literature published from 1963 to September 2022, as well as the UAMIZ herbarium database, were reviewed to complement and update the records. For the taxonomic determination of the specimens, an external morphological study was carried out. The synonymy and nomenclatural status were reviewed in AlgaeBase. From the records obtained, a graphic analysis was performed . Key results: An updated list with 113 species of estuarine macroalgae is presented: 62 Rhodophyta, 26 Phaeophyceae, Ochrophyta and 25 Chlorophyta, distributed in 24 orders, 38 families and 68 genera. Conclusions: According to what was observed, there are few or no phycological studies in Veracruz estuarine environments, which causes a gap in the context of the diverse estuarine macroalgae. This list, in addition to being an updated contribution for Veracruz, is a starting point to undertake future analyses that help establish areas of biological importance in these environments, in order to maximize diversity. In addition, the need for constant phycofloristic monitoring in estuaries is evident.

Resumen Las macroalgas dependen de sustratos específicos para su crecimiento y propagación. Esta relación es importante para comprender el funcionamiento de los arrecifes de coral. En México, sin embargo, los estudios sobre este tema son escasos. Así, en el presente estudio se determinó la diversidad de especies de macroalgas en el Parque Nacional Arrecifes de Xcalak (PNAX), en relación con el sustrato que colonizan. En julio del 2012, se seleccionaron 10 sitios de muestreo en 4 zonas del PNAX: canal de Zaragoza (C), laguna arrecifal 1 (LA1), laguna arrecifal 2 (LA2), y arrecife frontal (AF). Con ayuda de transectos y cuadrantes se recolectaron manualmente especímenes de 61 taxones de macroalgas (entre ellos un morfotipo), principalmente rodofitas, sobre 3 sustratos abióticos y 18 bióticos. De estos taxones, 17 especies constituyeron nuevos registros para el PNAX y 1 para la costa de Quintana Roo. La diversidad fue mayor en LA (3.89), seguido de AF (3.71), observando especies comunes entre ambas zonas. Las familias Halimedaceae, Udoteaceae y Anadyomenaceae se observaron creciendo sobre sustrato abiótico, mientras que las familias Halimedaceae y Dictyotaceae constituyeron sustrato para otras rodofitas. El número de macroalgas registrado en el PNAX representa 10.4% del total registrado para la costa de Quintana Roo.

Abstract Macroalgae depend on specific substrata for their growth and propagation. This relationship is essential to understand the functioning of coral reefs. In Mexico, however, studies on this subject are scarce. Therefore, in the present study, the diversity of macroalgae species in the Xcalak Reefs National Park (PNAX) was determined in relation to the substrata they colonize. In July 2012, 10 sampling sites were selected in 4 zones of the PNAX: Zaragoza Canal (C), Lagoon Reef 1 (LA1), Lagoon Reef 2 (LA2), and Fore Reef (AF). With the help of transects and quadrants, specimens of 61 taxa of macroalgae (among them a morphotype) were collected manually, mainly Rhodophyta, on 3 abiotic and 18 biotic substrata. Of these taxa, 17 species were new records for the PNAX and 1 for the Quintana Roo’s coast. The diversity was higher in LA (3.89), followed by AF (3.71), observing common species between both zones. The families Halimedaceae, Udoteaceae, and Anadyomenaceae were observed growing on abiotic substrata, while the families Halimedaceae and Dictyotaceae constituted substrata for other Rhodophyta. The number of macroalgae registered in the PNAX represents 10.4% of the total registered for Quintana Roo’s coast.

ABSTRACT In this paleoecological study we focused on coralline red algae-rich shoal grainstone facies in the Lower Miocene (Aquitanian) carbonates of the Qom Formation in the Vartun section in central Iran. The identified coralline red algae are mainly non-geniculate, although very rare geniculate forms of corallines were also recognized in thin section analysis. The identified algae are represented by Melobesioideae (Lithothamnioncf.valens,Lithothamnioncf.rovereoti,Lithothamnioncf.peleense, andLithothamnionspp.), Mastophoroideae (Neogoniolithonsp.,Spongitesspp., andSpongitescf.fruticulosus),Sporolithonspp. (Sporolithonspp. andSporolithoncf.airoldii), and geniculate coralline (Corallina). The algal taxa mainly display fruticose and lumpy growth forms. The dominance of the former is consistent with high water energy in the identified shoal environment. The presence of Lower Miocene algae indicates that deposition of carbonates took place in warm tropical to subtropical waters in a euphotic marine environment during the Aquitanian. Likewise, high water energy and sediment agitation resulted in taphonomic features such as fragmentation, abrasion, and disarticulation.

RESUMEN En este estudio paleoecológico se enfocó en las facies grainstone rica en algas rojas coralinas en los carbonatos del Mioceno Inferior (Aquitaniano) de la Formación Qom en la sección Vartun del centro de Irán. Las algas rojas coralinas identificadas en las facies son principalmente no geniculadas, aunque también se caracterizaron formas geniculadas mediante análisis de láminas delgadas. Las algas identificadas están representadas por Melobesioidea (Lithothamnioncf.valens,Lithothamnioncf.rovereoti,Lithothamnioncf.peleense, yLithothamnionspp.), Mastophoroidea (Neogoniolithonsp.,Spongitesspp., ySpongitescf.fruticulosus),Sporolithonspp (Sporolithonspp. ySporolithoncf.airoldii), y por coralinas geniculadas (Corallina). Los taxones de algas muestran principalmente formas grandes y grumosas de fructicoso. Donde predomina consistentemente con alta energía del agua en el ambiente arrecifal identificado. La presencia de algas del Mioceno Inferior indica que la exposición de carbonatos tuvo lugar en aguas cálidas tropicales a subtropicales en la zona eufótica marina durante el Aquitaniano. Asimismo, tanto la alta energía del agua como la agitación de los sedimentos, dieron lugar a características tafonómicas tales como fragmentación, abrasión, y desarticulación.

RESUMEN Esta investigación es un aporte al conocimiento de algunas especies de macroalgas marinas que fueron recolectadas durante las expediciones científicas “Almirante Padilla” (2016-2017) y “Almirante Campos” (2018-2019), en las que participó el Instituto de Investigaciones Marinas y Costeras-Invemar con el proyecto: Biodiversidad y Condiciones Oceanográficas del Estrecho de Gerlache “Biogerlache-Antártica”. Se realizaron recolectas usando draga tipo Shipek y videos subacuáticos con un ROV (Remote Operated Vehicle). Se identificaron seis especies, cuatro Rhodophyta y dos Ochrophyta-Phaeophyceae. Se incluye información sobre la profundidad y zonación donde las macroalgas fueron halladas, y su relación con registros previos para el área de estudio.

ABSTRACT This research is a contribution to the knowledge of some marine macroalgae species collected during the “Admiral Padilla” (2016-2017) and “Admiral Campos” (2018-2019) scientific expeditions, in which the Marine and Coastal Research Institute-Invemar participated with the project “Biodiversity and Oceanographic Conditions of the Gerlache Strait-Biogerlache-Antartica”. Samples were taken using a Shipek dredge; and underwater video recordings were made with a ROV (Remote Operated Vehicle). Six (6) species were identified: four (4) Rhodophyta and two (2) Ochrophyta-Phaeophyceae. Depth and zonation information where the macroalgae were found is included, and their relationship with previous records for the study area.

RESUMO Apresentamos um inventário com 23 táxons da flora ficológica bentônica em praias da costa nordeste do estado do Pará, na Amazônia brasileira, uma região raramente amostrada para algas. As coletas foram realizadas em substratos como matacões no município de Salinópolis, e em troncos, galhos e pneumatóforos de Laguncularia racemosa e substratos artificiais no município de Marapanim. Apesar das limitações da amostragem, nós registramos dez novas citações de algas marinhas e estuarinas bentônicas para a costa do estado do Pará: seis Chlorophyta (Bryopsis pennata, Cladophora coelothrix, C. conferta,Gayralia brasiliensis, Pseudorhizoclonium africanum e Ulva chaetomorphoides), duas Rhodophyta (Caloglossa confusa e Centroceras gasparrinii), uma Ochrophyta (Bachelotia antillarum) e uma Cyanophyta (Coleofasciculus chthonoplastes).

ABSTRACT We present a checklist with 23 taxa of the benthic phycological flora on three beaches on the northeast coast of Pará state, in the Brazilian Amazon, a rarely surveyed area for algae. Collections were made on substrates like rocky outcrops at Salinópolis municipality, and on trunks, branches and pneumatophores of Laguncularia racemosa and artificial substrates at Marapanim municipality. Despite the limited geographic scale of the sampling, we provide ten new citations for the benthic, marine and estuarine algal taxa of the Pará state coast: six Chlorophyta (Bryopsis pennata, Cladophora coelothrix, C. conferta, Gayralia brasiliensis, Pseudorhizoclonium africanum and Ulva chaetomorphoides), two Rhodophyta (Caloglossa confusa, Centroceras gasparrinii), one Ochrophyta (Bachelotia antillarum) and one Cyanophyta (Coleofasciculus chthonoplastes).

RESUMEN Las raíces de Rhizophora mangle proveen un hábitat de guardería para muchas especies debido a la estructura tridimensional que forman, lo cual delimita un área de difícil acceso para depredadores grandes. Adicionalmente, proveen un sustrato duro para muchas especies bentónicas, que se atan a las raíces y contribuyen a la estructura tridimensional del ecosistema. Entre esos organismos, encontramos varias macroalgas, que contribuyen a la productividad primaria del ecosistema y proveen alimento y refugio a los herbívoros. En el presente estudio se identificaron las macroalgas asociadas a las raíces de Rhizophora mangle, en playa Cholón, en las islas del Rosario, Caribe colombiano. Se reportan 36 especies of macroalgas: 21 Rhodophyta, once Chlorophyta y cuatro Phaeophyceae. De esas 36 especies, 19 son nuevos registros para las islas, y otros seis son nuevos registros para Colombia. Este es el primer estudio sobre las macroalgas asociadas a las raíces de manglar en el Caribe colombiano, e ilustra tanto la alta diversidad de la flora marina en el Caribe suroccidental, como la falta de estudios sobre el tema.

ABSTRACT The roots of the red mangrove, Rhizophora mangle, provide a nursery habitat for many species, due to the tridimensional structure they provide, which delimits an area difficult to access to large predators. Moreover, they provide a hard substrate for many benthonic species, which attach to the roots and contribute to the tridimensional structure of the ecosystem. Among these organisms, there are several macroalgae, which contribute to the primary productivity of the ecosystem and provide food and shelter to herbivores. In the present study we identified the macroalgae associated with the roots of Rhizophora mangle, in Cholón beach, Rosario Islands National Park, Caribbean Colombia. We report a total of 36 species of macroalgae: 21 Rhodophyta, eleven Chlorophyta, and four Phaeophyceae. Of these, 19 are new records for the islands, and six are new records for Colombia. This is the first study on the macroalgae associated with mangrove roots in the Colombian Caribbean, and it highlights both the high diversity of the marine flora of the Southwestern Caribbean, as well as the paucity of studies on the topic.

ABSTRACT Background: Since 2011, the coasts of North America, Mexico, and the Caribbean have experienced an unusual increase in the arrival of Sargassum. As a consequence of this massive accumulations of Sargassum holopelagic species in Caribbean Sea have been generated and that threaten local biodiversity and trigger economic losses associated with beach deterioration and impact on fisheries and tourism. Goals: This document quantifies the occurrence of an excessive drift of Sargassum in two sites (Puerto Viejo and Punta Uva) of the Caribbean coast of Costa Rica, Limón province, in March-April of 2019. A macroalgae species checklist is presented from six sites (Punta Cahuita, Puerto Vargas, Puerto Viejo, Playa Chiquita, Punta Uva and Manzanillo) in the Caribbean. In addition, the Sargassum morphotypes are quantified for the study area. Methods: Transects (50 m) were located parallel to the shoreline and, in points previously estimated, a quadrat of 25 x 25 cm covered the entire Sargassum band width on the beach until the water line, by fliping the quadrats and collecting the biomass for as many quadrats were necessary for the band. Then, pelagic Sargassum biomass was weighted in every point, and the dry weight biomass was estimated. Three quadrats were collected by the transect method. Associated species were identified as well as Sargassum morphotypes in all sites. Results: Descriptions that illustrate the morphology of the three morphotypes of pelagic species. The putatively rare S. natans VIII dominated the dritf (65 % dry weight), followed by S. natans I (25% dry weight), and S. fluitans (10 % dry). Twenty eight species were identified from Chlorophyta (9), Ochrophyta (15), and Rhodophyta (4) Divisions. Conclusions: There were no significant differences between months (March-April) and sites (Puerto Viejo and Punta Uva) for the dritf biomass.

RESUMEN Antecedentes: Desde 2011, las costas de América del Norte, México y el Caribe han experimentado un aumento inusual en la llegada de Sargassum de arribazón. Como consecuencia, se han generado acumulaciones masivas de especies holopelágicas del género Sargassum en áreas costeras del Caribe que amenazan la biodiversidad local y desencadenan pérdidas económicas asociadas con el deterioro de las playas y el impacto en la pesca y el turismo. Objetivo: Se cuantifica la presencia de una deriva excesiva de Sargassum en dos sitios (Puerto Viejo y Punta Uva) de la costa caribeña de Costa Rica, provincia de Limón, en los meses de marzo y abril de 2019. Se presenta la lista de especies de macroalgas conspicuas asociadas al fenómeno en seis sitios (Punta Cahuita, Puerto Vargas, Puerto Viejo, Playa Chiquita, Punta Uva y Manzanillo) en el Caribe. Además, se cuantifican los morfotipos de Sargassum para el área de estudio. Métodos: Se ubicaron transectos (50 m) paralelos a la línea de costa y, en puntos previamente estimados, un cuadrante de 25 x 25 cm cubrió todo el ancho de banda de Sargassum en la playa hasta la línea de flotación, volteando los cuadrantes y recolectando la biomasa para tantos cuadrantes como fueron necesarios para la cubrir la zona arribada. Luego, se pesó la biomasa pelágica de Sargassum en cada punto, y se estimó la biomasa en peso seco. Se recolectaron tres cuadrantes mediante el método de transectos. Se identificaron especies asociadas, así como morfotipos de Sargassum en todos los sitios. Resultados: se presenta la morfología de los tres morfotipos de especies pelágicas. El supuestamente raro S. natans VIII dominó el arribo de algas (65% de peso seco), seguido por S. natans I (25% de peso seco), S. fluitans (10% de peso seco). Se identificaron 28 especies de las Divisiones: Chlorophyta (9), Ochrophyta (15) y Rhodophyta (4). Conclusiones: No existen diferencias significativas entre meses (marzo-abril) y sitios (Puerto Viejo y Punta Uva) para la biomasa arribada.

Abstract: The marine ecoregions of Canals and Fjords of Southern Chile and Magellan Sub-Antarctic represent the extreme southern latitude limit for the distribution of numerous organism group. In southern Hemisphere, the most austral distribution site of kelps formation is placed at Diego Ramírez Archipelago, where Lessonia flavicans, L. searlesiana and Macrocystis pyrifera have been registered. Diego Ramírez Archipelago is located in the Drake Passage, 112 km southwest to Cape Horn. Regarding the available information for macroalgae, a total of 79 taxa has been reported, many of which show a sub-Antarctic and Antarctic affinity. Despite the biogeographic interest of the macroalgae from Diego Ramírez Archipelago, there have not been new cadasters to evaluate whether this archipelago could represent the northern boundary of the Antarctic species distribution and/ or the southern boundary of Magellan species. The goal of this study is to update the cadaster of macroalgae from Diego Ramírez Archipelago, in order to find new taxa and contribute to the analysis of the biogeographic relationships of its phycoflora. From the sampling campaign at Gonzalo Island, 19 taxa of macroalgae were identified. In terms of richness by division, Chlorophyta was represented by 3 species (16%), Ochrophyta by 7 taxa (37%), and Rhodophyta by 9 taxa, representing the 47% of the identified flora. Thus, the present study combines our new registers together with the previous findings, providing an updated cadaster of macroalgae of the archipelago, suggesting a total of 86 taxa. Overall, it can be stated that all registered species of the archipelago show a sub- Antarctic affinity.

Resumen: Las ecorregiones marinas de canales y fiordos del sur de Chile subantártica de Magallanes representan el límite extremo de latitud sur para la distribución de numerosos grupos de organismos. En el caso del Hemisferio Sur, el punto de distribución más austral de representantes de las formaciones de “kelps” se encuentra en el archipiélago Diego Ramírez, donde se registran las especies Lessonia flavicans, L. searlesiana y Macrocystis pyrifera. El archipiélago Diego Ramírez se encuentra ubicado en el Paso Drake a 112 km al SO del Cabo de Hornos. Con respecto a la información disponible para macroalgas se ha informado un total de 79 taxa, de los cuales muchos presentan afinidad subantártica-antártica. Pese al interés biogeográfico de las macroalgas del archipiélago Diego Ramírez, no ha habido nuevos catastros que permitan evaluar si este archipiélago podría representar el extremo norte de distribución de especies antárticas y/o el extremo sur de especies magallánicas. El objetivo de este trabajo es actualizar el catastro de macroalgas del archipiélago con el fin de detectar nuevos taxa que pudieran estar presentes en estas islas, así como contribuir al análisis de las relaciones biogeográficas de su ficoflora. De la campaña realizada en la isla Gonzalo se identificó un total de 19 taxa de macroalgas. En términos de riqueza por división, Chlorophyta estuvo representada por 3 especies (16%), Ochrophyta por 7 taxa (37%) y Rhodophyta por 9 taxa, representando el 47% de la flora identificada. Con estos nuevos registros y los de trabajos previos, nuestro estudio genera un catastro actualizado de macroalgas para el archipiélago que concluye en la presencia de 86 taxa. En general, se pudo observar que las especies registradas durante este estudio y los trabajos previos analizados presentan afinidad subantártica.