Statistical relationships of cnidocyst sizes in the sea anemone Oulactis muscosa (Actiniaria: Actiniidae)

This study analysis the multivariate statistical relationships among cnidocyst types and tissues in terms of cnidocyst capsule size in the sea anemone O. muscosa. In a total of 12 individuals we measured the length of 30 unfired capsules of each cnida type, taken randomly from each of the following tissues: tentacles, acrorhagi, column, actinopharynx and mesenterial filaments. In these tissues, we found spirocysts, basitrichs, microbasic b-mastigophores, microbasic p-mastigophores and holotrichs. Thus, a total of 5400 measurements were made. Looking for a common pattern of variation, a principal components analysis (PCA) was performed on the data matrix, among cnidocyst types for each tissue and between tissues for each cnidocyst type. The results showed that the lengths of most cnidocysts, whether from the same or different tissues, are not statistically related to each other, suggesting that different forces (cnidogenesis, replacement dynamics, etc.), could affect in various forms the development and therefore the length of each cnida, depending on the type or tissue of origin.Fil: Acuña, Fabian Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentin

New record for the distribution of the colonial hydroid Cordylophora caspia (Pallas, 1771) (Cnidaria: Hydrozoa) in Argentina

Cordylophora caspia is a colonial, athecate hydroid inhabiting both in freshwater and brackish habitats. Its global distribution is in part due to its ability to tolerate a wide range of salinity. It is considered an invasive species and its control is widely studied because of the industrial and ecological problems it causes in many environments. We report for the first time the occurrence of this hydrozoan in Nahuel Rucá Lake (Buenos Aires province, Argentina) with some notes on its internal and external morphology.Fil: Deserti, Maria Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Escalante, Alicia Haydee. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Acuña, Fabian Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentin

Trophic ecology of the intertidal sea anemone Bunodosoma zamponii (cnidaria, actiniaria): Diet composition, seasonal variation and trophic parameters

Sea anemones are considered as polyphagous opportunistic predators and it has been suggested that their diet reflects the structure of the community they inhabit. The feeding ecology of intertidal species is an interesting topic to study due to their wide variety of strategies to obtain food. In this sense, we studied the diet of Bunodosoma zamponii, the most abundant actiniarian in the rocky intertidal of Punta Cantera (Mar del Plata, Argentina). The objectives were to describe it and compare its composition seasonally and between diurnal and nocturnal high tides. We examined the gastric cavity content of 154 specimens collected seasonally at both diurnal and nocturnal high tides, and 39 different prey items were identified, some of which are recorded here for the first time for this species. No variations on diet composition were found between seasons or between diurnal and nocturnal high tides, suggesting that the food available does not vary either. Bunodosoma zamponii ingests mostly items with low biomass, which contribute to the total biomass ingested in direct proportion to their frequency in the diet. The bivalve Brachidontes rodriguezii was the main prey for the anemone, followed to a lesser extent by certain amphipods, other mollusks and algae.Fil: Erralde, Stefanía Micaela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Acuña, Fabian Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina. Estación Científica Coiba; Panam

The sea anemone Bunodactis octoradiata (Anthozoa: Actiniaria) from southern Patagonia: morphological study and new records

Bunodactis Verril, 1899 comprises at present 19 nominal species of sea anemones. The validity of the genus is under discussion. The description of the species, Bunodactis octoradiata Carlgren, 1899, is insufficient for reliable identification, and although subsequent works have provided additional information on the species, its description still needs to be complemented. Herein we describe B. octoradiata based on histological sections of the internal anatomy, and give a complete and detailed description of the external anatomy. The cnidom is composed of spirocysts, basitrichs and microbasic p-mastigophores; their distribution in the organism, sizes and relative abundances are provided. The presence of zooxanthellae is reported for the first time. Bunodactis octoradiata is distributed in groups that vary from 5.6 to 45 ind./m2 in the field. Additionally, our data extends the distribution of the species along the coast of southern Patagonia (47°44'36"-49°15'13"S and 65°50'26"-67°39'45"W).Fil: Garese, Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Longo, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Martin, Juan Pablo. Universidad Nacional de la Patagonia Austral. Unidad Academica San Julian; ArgentinaFil: Acuña, Fabian Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentin

Feeding Behavior of Spurilla sp. (Mollusca: Opisthobranchia) with a Description of the Kleptocnidae Sequestered from Its Sea Anemone Prey

Feeding behavior of Spurilla sp. (Mollusca: Opisthobranchia) with a description of the kleptocnidae sequestered from its sea anemone prey. Zoological Studies 51(7): 905-912. Cnidocysts are sequestered from cnidarian prey by aeolid nudibranchs and stored in the tips of their appendages (cerata). The kleptocnidae of 11 specimens of Spurilla sp. are described in detail. The types and relative abundances of prey cnidocysts in nudibranch cerata were highly variable, suggesting exclusive anemone consumption. Spirocysts and several types of microbasic p-mastigophores, microbasic b-mastigophores, and basitrichs were found in external and internal tissues of sea anemone prey. This is the 1st report of predation of aeolid Spurilla sp. on the sea anemones Antholoba achates, Metridium senile lobatum, and Parabunodactis imperfecta from the rocky intertidal of Patagonia (Chubut Province, Argentina) and on Anthothoe chilensis and Tricnidactis errans at Mar del Plata (Buenos Aires Province, Argentina). Photographs and digital videos of aeolidacean feeding behavior were recorded in situ and in aquaria. The purpose of this study was to provide valuable information on the diet of Spurilla sp. from Argentina using field observations and descriptions of the kleptocnidae.Fil: Garese, Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: García Matucheski, Stella. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. San Martín; ArgentinaFil: Muniain, Claudia Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Acuña, Fabian Horacio. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. San Martín; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Cnidom variation through distinct developmental stages in the sea anemone Aulactinia marplatensis (Zamponi, 1977) (Cnidaria: Actiniaria)

The cnidae are the exclusive diagnostic structures of phylum Cnidaria. The inventory of all cnidae types of a particular species is called the cnidom. The study of cnidae has been widely addressed in all classes of cnidarians. Particularly in the order Actiniaria (sea anemones), the study of the composition, size and distribution of cnidae is essential to the identification and description of species. In the present study, we examine the cnidom of the sea anemone Aulactinia marplatensis in three different stages of development throughout its life cycle. We found that the composition and abundance patterns are very similar between the adult and juvenile stages, although significant differences in the size capsules were found between both stages and in all cnidae types observed, being bigger those from the adult forms. The planula larvae stage presents a less diverse cnidom in comparison to the juvenile and adult stages; however, it present an exclusive cnidae type (the mesobasic p-mastigophore) which is the biggest in size of all the cnidae types observed in the species. These results highlight the importance of considering the stage of development when cnidae is used as a diagnostic character, and the particular relevance of the study of the cnidom in larval stages.Fil: Garese, Agustin. Laboratorio de Biología de Cnidarios; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: González Muñoz, Ricardo Enrique. Laboratorio de Biología de Cnidarios; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Acuña, Fabian Horacio. Laboratorio de Biología de Cnidarios; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentin

Hydra-Amoeba system: a double infection with a lethal ending

Within each ecosystem, organisms and populations maintain a complex set of relationships. These interactions can determine the distribution area of a species and play an essential role in its evolution. Parasites are ubiquitous components of nature and have a high influence on various aspects of the biology and ecology of organisms, affecting the populations of their hosts and, therefore, their communities and ecosystems. Free-living amoebae are unicellular organisms that can be found in water, soil or air. Some species are of great importance in human health. In Hydra, there are several reports of Hydramoeba hydroxena infections. In this work we present a double parasitosis: two concatenated infectious periods in the host polyp of Hydra vulgaris and Hydra vulgaris pedunculata for three freshwater bodies in the province of Buenos Aires, Argentina. Hydramoeba sp. and Acanthoamoeba sp. unchain a series of anatomical lesions that in all cases cause the death of the polyps due to total disintegration. This finding becomes important at a sanitary level due to the appearance of Acanthoamoeba sp. in waters associated with human recreational activities; For the Hydra genus, the importance lies at an ecological and evolutionary level, considering the possible impact on its natural populations.Fil: Deserti, Maria Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias Marinas. Laboratorio de Biología de Cnidarios; ArgentinaFil: Lorenzo Morales, Jacob. Universidad de La Laguna; España. Centro de Investigación Biomédica En Red de Enfermedades Infecciosas; EspañaFil: Acuña, Fabian Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias Marinas. Laboratorio de Biología de Cnidarios; Argentina. Estación Científica Coiba; Panam

New Records of Sea Anemones (Cnidaria: Anthozoa) from Costa Rica

A pesar de ser componentes importantes en los sistemas marino-costeros, las anémonas de mar han sido poco estudiadas en las costas de Costa Rica. En el presente trabajo se dan a conocer registros nuevos de anémonas de mar para las costas del Caribe y Pacífico de Costa Rica, incluyendo el Parque Nacional Isla del Coco. Se han confirmado también la presencia de otras especies que habían sido registradas para Costa Rica, pero sólo en base a observaciones visuales o fotografías. Se actualiza el inventario de este grupo de cnidarios que, junto a los corallimorpharios, está constituido por 16 especies (10 en el Caribe y 6 en el Pacífico e Isla del Coco). Asimismo, se realiza una comparación entre las faunas de anémonas de mar de Costa Rica y Panamá.Despite being important components in coastal marine systems, sea anemones have been poorly studied on both coasts of Costa Rica. In this paper new records of sea anemones are mentioned for the Caribbean and Pacific coasts of Costa Rica and the Isla del Coco National Park. Additionally, the presence of other species previously recorded in Costa Rica based on single observations or photos, is reconfirmed. An updated inventory of these cnidarians is provided, and with the corallimorpharians, comprises of 16 species (10 in the Caribbean and 6 in the Pacific and Coco Island). A comparison with the sea anemone fauna of Panama is added.Fil: Acuña, Fabian Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Mar del Plata. Instituto de Investigaciones Marinas y Costeras; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina;Fil: Garese, Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Mar del Plata. Instituto de Investigaciones Marinas y Costeras; Argentina; Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias Marinas; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina;Fil: Excoffon, Adriana Carmen. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias Marinas; Argentina; Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias Marinas. Laboratorio de Biología de Cnidarios; Argentina;Fil: Cortés, Jorge. Universidad de Costa Rica. Centro de Investigación en Ciencias del Mar y Limnología; Costa Rica; Universidad de Costa Rica. Escuela de Biología; Costa Rica

Diversity of Feeding in Anthozoa (Cnidaria): A Systematic Review

In this study, we performed a bibliographical review examining the scientific literature on “feeding in Anthozoa” for the period from 1890 to 2019, using the scientific database Google Scholar, supplemented with additional literature. This study categorized published scientific papers on this topic by decade of publication, target taxa, variability of species studied in each order and main themes studied. As a result, 153 studies were found, and based on their content, it was observed that within Anthozoa, there has been a concentration of feeding studies on species in the orders Actiniaria (Hexacorallia), Scleractinia (Hexacorallia), and Alcyonacea (Octocorallia). This indicates that the other remaining orders of the group have been comparatively neglected with regards to their feeding aspects. Therefore, as data on feeding in some groups of Anthozoa are scarce, studies need to be carried out to fill the gaps that permeate this important benthic group, in order to better understand their ecology.Fil: Barbosa Santos, Thais. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Reimer, James D.. University Of The Ryukyus; JapónFil: Acuña, Fabian Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Stampar, Sergio. Universidade Estadual Paulista Julio de Mesquita Filho; Brasi

Cnidom in Ceriantharia (Cnidaria, Anthozoa): new findings in the composition and micrometric variations of cnidocysts

Background: Like all cnidarians, the subclass Ceriantharia (Cnidaria, Anthozoa) is known for producing cnidocysts, which mainly serve for prey immobilization, predator defense, and locomotion. Aim: The present study aimed to understand the variability of the cnidom, i.e., the inventory of all cnidocyst types, in the ceriantharians (tube anemones) Ceriantheomorphe brasiliensis (10 individuals) and Cerianthus sp. (seven individuals). Methods: In each individual, 30 intact cnidocysts of each identified type were measured in the following parts of tube anemones: marginal tentacles (four from each individual), labial tentacles (four from each individual), column, actinopharynx and metamesenteries. Each of these structures was divided into three levels (high, middle, and low) and the cnidom was analyzed. Statistical descriptive parameters (mean, standard deviation, minimum and maximum) of the sizes of all types of cnidocysts were calculated. The normality of the data for cnidocyst length was assessed using a Shapiro-Wilk test (a = 0.05). Based on the acceptance or rejection of the normality, either linear models or generalized linear models were used to evaluate variations in cnidocyst lengths. The normality of the cnidocyst length was tested by Shapiro-Wilk, and due to its rejection, generalized linear mixed models were applied to test the cnidocyst lengths variations. Results: The analysis of Ceriantheomorphe brasiliensis revealed 23 categories of cnidocysts, thereby expanding the understanding of its cnidome. The cnidoms of Ceriantheomorphe brasiliensis and Cerianthus sp. presented intraspecific variations, both qualitatively and in the lengths of cnidocysts. The cnidoms of the two species studied also showed qualitative intra-individual variations between different levels (high, middle, low) within each structure of the tube anemone (tentacles, actinopharynx, column and metamesenteries). Some cnidocyst types, such as atrichs from the column of C. brasiliensis, presented a length gradient along the column, from larger lengths at the “low” level to smaller lengths at the “high” level. Conclusions: The cnidom of a tube anemone could be better described if samples are taken at different levels of the structures, as observed in C. brasiliensis. In addition, we can conclude that the cnidocyst lengths of both C. brasiliensis and Cerianthus sp. present intraspecific variation, which is coincident with that observed in actiniarian sea anemones. Moreover, as main conclusion, this work also proved that individuals of tube anemone species could present qualitative intra-structure variations in both the cnidom and cnidocyst lengths. This characteristic appears as an exception in cnidom variations, and has so far not been recorded even in the most studied actiniarian sea anemones. Finally, the intra-structure cnidocyst variations could reveal different functions of the different levels of a particular body part of the organisms.Fil: Garese, Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Goes Correa, Fabiola. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Acuña, Fabian Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Stampar,Nascimento Stampar, Sérgio. Universidade Estadual Paulista Julio de Mesquita Filho; Brasi