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1.
PLoS One ; 14(6): e0218086, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31188894

RESUMO

The evaluation of large amounts of digital image data is of growing importance for biology, including for the exploration and monitoring of marine habitats. However, only a tiny percentage of the image data collected is evaluated by marine biologists who manually interpret and annotate the image contents, which can be slow and laborious. In order to overcome the bottleneck in image annotation, two strategies are increasingly proposed: "citizen science" and "machine learning". In this study, we investigated how the combination of citizen science, to detect objects, and machine learning, to classify megafauna, could be used to automate annotation of underwater images. For this purpose, multiple large data sets of citizen science annotations with different degrees of common errors and inaccuracies observed in citizen science data were simulated by modifying "gold standard" annotations done by an experienced marine biologist. The parameters of the simulation were determined on the basis of two citizen science experiments. It allowed us to analyze the relationship between the outcome of a citizen science study and the quality of the classifications of a deep learning megafauna classifier. The results show great potential for combining citizen science with machine learning, provided that the participants are informed precisely about the annotation protocol. Inaccuracies in the position of the annotation had the most substantial influence on the classification accuracy, whereas the size of the marking and false positive detections had a smaller influence.


Assuntos
/métodos , Aprendizado Profundo , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Biologia Marinha/métodos , Animais , Organismos Aquáticos , Artrópodes/anatomia & histologia , Artrópodes/classificação , Cnidários/anatomia & histologia , Cnidários/classificação , Equinodermos/anatomia & histologia , Equinodermos/classificação , Humanos , Imageamento Tridimensional , Biologia Marinha/instrumentação , Moluscos/anatomia & histologia , Moluscos/classificação , Poríferos/anatomia & histologia , Poríferos/classificação
2.
J R Soc Interface ; 16(150): 20180630, 2019 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-30958143

RESUMO

Leuconoid sponges are filter-feeders with a complex system of branching inhalant and exhalant canals leading to and from the close-packed choanocyte chambers. Each of these choanocyte chambers holds many choanocytes that act as pumping units delivering the relatively high pressure rise needed to overcome the system pressure losses in canals and constrictions. Here, we test the hypothesis that, in order to deliver the high pressures observed, each choanocyte operates as a leaky, positive displacement-type pump owing to the interaction between its beating flagellar vane and the collar, open at the base for inflow but sealed above. The leaking backflow is caused by small gaps between the vaned flagellum and the collar. The choanocyte pumps act in parallel, each delivering the same high pressure, because low-pressure and high-pressure zones in the choanocyte chamber are separated by a seal (secondary reticulum). A simple analytical model is derived for the pump characteristic, and by imposing an estimated system characteristic we obtain the back-pressure characteristic that shows good agreement with available experimental data. Computational fluid dynamics is used to verify a simple model for the dependence of leak flow through gaps in a conceptual collar-vane-flagellum system and then applied to models of a choanocyte tailored to the parameters of the freshwater demosponge Spongilla lacustris to study its flows in detail. It is found that both the impermeable glycocalyx mesh covering the upper part of the collar and the secondary reticulum are indispensable features for the choanocyte pump to deliver the observed high pressures. Finally, the mechanical pump power expended by the beating flagellum is compared with the useful (reversible) pumping power received by the water flow to arrive at a typical mechanical pump efficiency of about 70%.


Assuntos
Flagelos/fisiologia , Hidrodinâmica , Modelos Biológicos , Poríferos/anatomia & histologia , Poríferos/fisiologia , Animais
3.
J Morphol ; 279(12): 1872-1886, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30506663

RESUMO

The main characteristic of sponges (Porifera) is the presence of the aquiferous system-a system formed by canals and choanocyte chambers, in which the sponges carry out most of their physiological functions. Despite of the importance for the biology of the group, the knowledge about this structure is still incipient, even when morphological investigations are taken in account. Here, we investigated the anatomy and ultrastructure of the tropical demosponge Cladocroce caelum (Haplosclerida, Demospongiae) using light and electron microscopy. In the studied region, specimens of this species were repent or repent-branched, possessing one to several oscula. A uniform and reduced atrium was found just below each osculum. There was a thin ectosome and the choanosome presented meager mesohyl, but a high number of choanocyte chambers. The choanocyte chambers were rounded, and, as in other haplosclerids, they are found separated from the mesohyl by endopinacocytes, "hanging" in the inhalant canals. Even though the utility of the general organization of the aquiferous system has been advocated as a possible tool to understand the phylogeny of the group, we found that these characters might not be as useful as expected. The size of the particles ingested by the sponge and the amount of bacteria to sustain their bodies are discussed. In addition, we found that the density of choanocyte chambers was reduced when the specimens were carrying out the spermatogenesis, indicating that the reproduction may impair the filtering activity of the sponge. Our findings consist in a first step to better comprehend the physiology, development, and adaptation to the environmental conditions where the species is found.


Assuntos
Poríferos/anatomia & histologia , Poríferos/ultraestrutura , Clima Tropical , Adaptação Fisiológica , Animais , Filogenia , Poríferos/citologia
4.
J Exp Zool B Mol Dev Evol ; 330(6-7): 351-371, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30421540

RESUMO

Sponges (Porifera) demonstrate prominent regeneration abilities and possess a wide variety of mechanisms, used during this process. In the current study, we combined in vivo observations with histological, immunohistochemical, and ultrastructural technics to elucidate the fine cellular mechanisms of the regeneration in the calcareous sponge Leucosolenia cf. variabilis. The regeneration of Leucosolenia cf. variabilis ends within 4-6 days. The crucial step of the process is the formation of the transient regenerative membrane, formed by the epithelial morphogenesis-spreading of the intact exopinacoderm and choanoderm. The spreading of the choanoderm is accompanied by the transdifferentiation of the choanocytes. The regenerative membrane develops without any contribution of the mesohyl cells. Subsequently, the membrane gradually transforms into the body wall. The cell proliferation is neither affected nor contributes to the regeneration at any stage. Thus, Leucosolenia cf. variabilis regeneration relies on the remodeling of the intact tissues through the epithelial morphogenesis, accompanied by the transdifferentiation of some differentiated cell types, which makes it similar to the regeneration in homoscleromorphs and eumetazoans.


Assuntos
Epitélio/fisiologia , Morfogênese , Poríferos/fisiologia , Regeneração/fisiologia , Animais , Transdiferenciação Celular , Poríferos/anatomia & histologia , Poríferos/citologia
6.
Proc Biol Sci ; 285(1881)2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29925613

RESUMO

Chancelloriids are an extinct group of spiny Cambrian animals of uncertain phylogenetic position. Despite their sponge-like body plan, their spines are unlike modern sponge spicules, but share several features with the sclerites of certain Cambrian bilaterians, notably halkieriids. However, a proposed homology of these 'coelosclerites' implies complex transitions in body plan evolution. A new species of chancelloriid, Allonnia nuda, from the lower Cambrian (Stage 3) Chengjiang Lagerstätte is distinguished by its large size and sparse spination, with modified apical sclerites surrounding an opening into the body cavity. The sclerite arrangement in A. nuda and certain other chancelloriids indicates that growth involved sclerite addition in a subapical region, thus maintaining distinct zones of body sclerites and apical sclerites. This pattern is not seen in halkieriids, but occurs in some modern calcarean sponges. With scleritome assembly consistent with a sponge affinity, and in the absence of cnidarian- or bilaterian-grade features, it is possible to interpret chancelloriids as sponges with an unusually robust outer epithelium, strict developmental control of body axis formation, distinctive spicule-like structures and, by implication, minute ostia too small to be resolved in fossils. In this light, chancelloriids may contribute to the emerging picture of high disparity among early sponges.


Assuntos
Evolução Biológica , Fósseis , Poríferos/crescimento & desenvolvimento , Animais , China , Fósseis/anatomia & histologia , Poríferos/anatomia & histologia
7.
PLoS One ; 13(5): e0195803, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29763421

RESUMO

Marine demosponges (Porifera: Demospongiae) are recognized as first metazoans which have developed over millions of years of evolution effective survival strategies based on unique metabolic pathways to produce both biologically active secondary metabolites and biopolymer-based stiff skeletons with 3D architecture. Up to date, among marine demosponges, only representatives of the Verongiida order have been known to synthetize biologically active substances as well as skeletons made of structural polysaccharide chitin. This work, to our knowledge, demonstrates for the first time that chitin is an important structural component within skeletons of non-verongiid demosponges Acarnus wolffgangi and Echinoclathria gibbosa collected in the Red Sea. Calcofluor white staining, FTIR and Raman analysis, ESI-MS, SEM, and fluorescence microscopy as well as a chitinase digestion assay were applied in order to confirm, with strong evidence, the finding of α-chitin in the skeleton of both species. We suggest that, the finding of chitin within these representatives of Poecilosclerida order is a promising step in the evaluation of these sponges as novel renewable sources for both biologically active metabolites and chitin, which are of prospective application for pharmacology and biomedicine.


Assuntos
Quitina/análise , Quitina/isolamento & purificação , Poríferos/metabolismo , Esqueleto/metabolismo , Animais , Quitina/metabolismo , Quitinases/metabolismo , Poríferos/anatomia & histologia , Esqueleto/anatomia & histologia
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 192: 368-377, 2018 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-29179087

RESUMO

The Demospongiae is the largest Class in the phylum Porifera (sponges). Most sponge species in the Class Demospongiae have a skeleton of siliceous spicules and/or protein spongin or both. The first aim of this study was to perform the morphological and structural characterization of the siliceous spicules of four species belonging to Class Demospongiae (Suberites domuncula, Axinella polypoides, Axinella damicornis and Agelas oroides) collected around Gökçeada Island-Turkey (Northern Aegean Sea). The characterizations were carried out using a combination of Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM/EDX), Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy (ATR-FTIR) and Small Angle X-ray Scattering (SAXS) techniques. The sponge Chondrosia reniformis (Porifera, Demospongiae) lacks a structural skeleton of spicules or the spongin. It consists mainly of a collagenous tissue. The collagen with sponge origin is an important source in biomedical and pharmaceutical applications. The second aim of this study was to provide more information on the molecular structure of collagen of outer (ectosome) and inner (choanosome) regions of the Chondrosia reniformis using ATR-FTIR spectroscopy. Hierarchical clustering analysis (HCA) was also used for the discrimination of ATR-FTIR spectra of species.


Assuntos
Ilhas , Oceanos e Mares , Poríferos/ultraestrutura , Animais , Análise por Conglomerados , Filogenia , Poríferos/anatomia & histologia , Espalhamento a Baixo Ângulo , Dióxido de Silício/química , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
9.
Annu Rev Genet ; 51: 455-476, 2017 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-28934592

RESUMO

The evolution of a nervous system as a control system of the body's functions is a key innovation of animals. Its fundamental units are neurons, highly specialized cells dedicated to fast cell-cell communication. Neurons pass signals to other neurons, muscle cells, or gland cells at specialized junctions, the synapses, where transmitters are released from vesicles in a Ca2+-dependent fashion to activate receptors in the membrane of the target cell. Reconstructing the origins of neuronal communication out of a more simple process remains a central challenge in biology. Recent genomic comparisons have revealed that all animals, including the nerveless poriferans and placozoans, share a basic set of genes for neuronal communication. This suggests that the first animal, the Urmetazoan, was already endowed with neurosecretory cells that probably started to connect into neuronal networks soon afterward. Here, we discuss scenarios for this pivotal transition in animal evolution.


Assuntos
Evolução Biológica , Comunicação Celular/fisiologia , Sistema Nervoso/metabolismo , Neurônios/metabolismo , Transmissão Sináptica/fisiologia , Animais , Cálcio/metabolismo , Sinalização do Cálcio/fisiologia , Cnidários/anatomia & histologia , Cnidários/fisiologia , Endossomos/fisiologia , Endossomos/ultraestrutura , Lisossomos/fisiologia , Lisossomos/ultraestrutura , Sistema Nervoso/citologia , Neurônios/citologia , Placozoa/anatomia & histologia , Placozoa/fisiologia , Poríferos/anatomia & histologia , Poríferos/fisiologia , Proteínas SNARE/genética , Proteínas SNARE/metabolismo , Vesículas Sinápticas/fisiologia , Vesículas Sinápticas/ultraestrutura , Vertebrados/anatomia & histologia , Vertebrados/fisiologia , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo
10.
Sci Rep ; 7(1): 5286, 2017 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-28706211

RESUMO

The two major extant groups of siliceous sponges, Demospongiae and Hexactinellida, are generally regarded as sister groups forming the clade Silicea, although the nature of their last common ancestor is uncertain. The fossil record contains a diverse range of basal demosponges that appear to have evolved from hexactine-bearing reticulosan ancestors, although a compelling morphological intermediate has not previously been discovered. Here we describe a new species of fossil sponge, Conciliospongia anjiensis gen. et sp. nov., from the Late Ordovician (~444 Ma) Anji Biota of South China. This species has a reticulate, tufted skeleton of minute monaxon spicules, characteristic of the fossil demosponge family Hazeliidae and modern heteroscleromorphs, with hexactine spicules and a globose body form inherited from reticulosan ancestors. This transitional morphology had previously been hypothesized in palaeontological studies. This morphological intermediate between two extant classes further confirms siliceous sponge monophyly and demosponge-hexactinellid spicule homology, and supports the primitive, stem-silicean interpretation of simpler-structured fossil reticulosans.


Assuntos
Evolução Molecular , Fósseis , Paleontologia , Filogenia , Poríferos/anatomia & histologia , Poríferos/classificação , Animais , Modelos Teóricos
11.
PLoS One ; 12(5): e0178350, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28542651

RESUMO

Sponges have a high capacity for regeneration and this process improves biomass production in some species, thus contributing to a solution for the biomass supply problem for biotechnological applications. The aim of this work is to characterize the dynamics of cell behavior during the initial stages of sponge regeneration, using bright-field microscopy, confocal microscopy and SEM. We focused on the first 20 h of regeneration, during which blastema formation and epithelium initialization occur. An innovative sponge organotypic culture of the regenerating internal region is described and investigated by confocal microscopy, cell transplantation and vital staining. Cell-cell interaction and cell density are shown to affect events in morphogenesis such as epithelial/mesenchymal and mesenchymal/epithelial transitions as well as distinct cell movements required for regeneration. Extracellular matrix was organized according to the morphogenetic process observed, with evidence for cell-signaling instructions and remodeling. These data and the method of organotypic culture described here provide support for the development of viable sponge biomass production.


Assuntos
Movimento Celular/fisiologia , Poríferos/fisiologia , Regeneração/fisiologia , Animais , Microscopia Confocal , Microscopia Eletrônica de Varredura , Poríferos/anatomia & histologia , Poríferos/citologia
12.
PLoS One ; 12(3): e0173859, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28329020

RESUMO

Although sponges are important components of benthic ecosystems of the Caribbean Sea, their diversity remained poorly investigated in the Lesser Antilles. By organizing a training course in Martinique, we wanted both to promote taxonomy and to provide a first inventory of the sponge diversity on this island. The course was like a naturalist expedition, with a field laboratory and a classroom nearby. Early-career scientists and environmental managers were trained in sponge taxonomy. We gathered unpublished data and conducted an inventory at 13 coastal sites. We explored only shallow water habitats (0-30 m), such as mangroves, reefs or rocky bottoms and underwater caves. According to this study, the sponge fauna of Martinique is currently represented by a minimum of 191 species, 134 of which we could assign species names. One third of the remaining non-identified sponge species we consider to be new to science. Martinique appears very remarkable because of its littoral marine fauna harboring sponge aggregations with high biomass and species diversity dominating over coral species. In mangroves, sponges cover about 10% of the surface of subtidal roots. Several submarine caves are true reservoirs of hidden and insufficiently described sponge diversity. Thanks to this new collaborative effort, the Eastern Caribbean has gained a significant increase of knowledge, with sponge diversity of this area potentially representing 40% of the total in the Caribbean Sea. We thus demonstrated the importance of developing exploratory and educational research in areas historically devoid of biodiversity inventories and systematics studies. Finally, we believe in the necessity to consider not only the number of species but their distribution in space to evaluate their putative contribution to ecosystem services and our willingness to preserve them.


Assuntos
Poríferos/classificação , Animais , Biodiversidade , Classificação , Ecologia/educação , Ecossistema , Martinica , Poríferos/anatomia & histologia , Zoologia/educação
13.
J Struct Biol ; 198(3): 186-195, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28323140

RESUMO

The skeletal system of Demospongiae consists of siliceous spicules, which are composed of an axial channel containing an organic axial filament (AF) surrounded by a compact layer of hydrated amorphous silica. Here we report the ultrastructural investigations of the AF of siliceous spicules from two Demospongiae: Suberites domuncula and Tethya aurantium. Electron microscopy, electron diffraction and elemental mapping analyses on both longitudinal and transversal cross-sections yield that spicules's AF consist of a three-dimensional crystal lattice of six-fold symmetry. Its structure, which is the result of a biological growth process, is a crystalline assembly characterized by a lattice of organic cages (periodicity in the range of 6nm) filled with enzymatically-produced silica. In general, the six-fold lattice symmetry is reflected by the morphology of the AF, which is characterized by six-fold facets. This seems to be the result of a lattice energy minimization process similar to the situation found during the growth of inorganic crystals. Our structural exploitation of three-dimensional organic lattices generated by biological systems is expected to contribute for explaining the relation between axial filament's ultrastructure and spicule's ultimate morphology.


Assuntos
Poríferos/anatomia & histologia , Dióxido de Silício/química , Animais , Cristalização , Análise de Elementos Finitos , Microscopia Eletrônica , Microscopia Eletrônica de Transmissão , Morfogênese , Compostos Orgânicos/química , Poríferos/química , Poríferos/crescimento & desenvolvimento , Poríferos/ultraestrutura , Suberites/ultraestrutura
14.
Sci Rep ; 7: 42945, 2017 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-28220860

RESUMO

Fossils of the sponge Angulosuspongia sinensis from calcareous mudstones of the middle and upper part of the Kaili Formation (Cambrian Stage 5) in the Jianhe area of Guizhou province, South China, exhibit an apparently reticulate pattern, characteristic of the Vauxiidae. Energy Dispersive X-Ray Spectrometry (EDS) and Raman spectroscopy analysis indicate the presence of silica in the skeletal elements of these fossils, suggesting that this taxon possessed a skeleton comprised of spicules. This is the first confirmation of siliceous skeletal elements in fossils of the family Vauxiidae, and it lends support to the hypothesis that some early demosponges possessed biomineralized siliceous skeletons, which were subsequently lost and replaced by spongin later in the evolutionary history of this lineage. The new materials provide critical insight into the phylogeny and evolution of biomineralization in the Demosopongiae.


Assuntos
Fósseis/anatomia & histologia , Dióxido de Silício/química , Animais , Evolução Biológica , China , Microscopia Eletrônica de Varredura , Poríferos/anatomia & histologia , Poríferos/química , Espectrometria por Raios X , Análise Espectral Raman
15.
Zootaxa ; 4217(1): zootaxa.4217.1.1, 2017 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-28183098

RESUMO

Sponges collected on the Guyana Shelf, predominantly in Suriname offshore waters, by Dutch HMS 'Snellius' O.C.P.S. 1966, HMS 'Luymes' O.C.P.S. II 1969, and HMS 'Luymes' Guyana Shelf 1970 expeditions are described in this study. Sponges were obtained by trawling, dredging or grabbing on sandy, muddy, shelly, and fossil reef bottoms at 88 stations between 19 and 681 m depth. A total of 351 samples were identified to species level, each consisting of one or more specimens of a given species from each individual station (together comprising 547 individuals and fragments). The collection yielded 119 species together belonging to all sponge classes, but in large majority are Demospongiae. All species are identified to species level, occasionally tentatively, and all are described and illustrated. A new subgenus is proposed, Tedania (Stylotedania) subgen. nov. and a previously synonymized genus, Tylosigma Topsent, 1894 is revived. Thirtysix species were found to be new to science, excluding the first Central West Atlantic record of the genus Halicnemia, not named at the species level because of lack of sufficient material. The new species erected are, in alphabetical order: Amphoriscus ancora sp. nov., Biemna rhabdotylostylota sp. nov., Callyspongia (Callyspongia) scutica sp. nov., Chelonaplysilla americana sp. nov., Cladocroce guyanensis sp. nov., Clathria (Axosuberites) riosae sp. nov., Clathria (Clathria) gomezae sp. nov., Clathria (Microciona) snelliusae sp. nov., Clathria (Thalysias) complanata sp. nov., Clathria (Thalysias) zeai sp. nov., Coelosphaera (Coelosphaera) lissodendoryxoides sp. nov., Craniella crustocorticata sp. nov., Diplastrella spirastrelloides sp. nov., Epipolasis tubulata sp. nov., Erylus rhabdocoronatus sp. nov., Erylus surinamensis sp. nov., Geodia pocillum sp. nov., Geodia sulcata sp. nov., Hemiasterella camelus sp. nov., Hymedesmia (Stylopus) alcoladoi sp. nov., Hymenancora cristoboi sp. nov., Penares sineastra sp. nov., Hymerhabdia kobluki sp. nov., Leucosolenia salpinx sp. nov., Petrosia (Strongylophora) devoogdae sp. nov., Placospongia ruetzleri sp. nov., Pyloderma tropicale sp. nov., Raspailia (Parasyringella) thamnopilosa sp. nov., Raspailia (Raspailia) johnhooperi sp. nov., Sphaerotylus bouryesnaultae sp. nov., Spirastrella erylicola sp. nov., Stelletta vervoorti sp. nov., Suberites crispolobatus sp. nov., Tedania (Stylotedania) folium subgen. nov. sp. nov., Timea tylasterina sp. nov., and Tylosigma ostreicola sp. nov. Two new combinations are proposed: Amphimedon nanaspiculata (Hartman, 1955) comb. nov. and Oceanapia ascidia (Schmidt, 1870) comb. nov. In addition, for two preoccupied combinations, new names, Coelosphaera (Coelosphaera) barbadensis nom. nov. and Hymedesmia (Hymedesmia) rowi nom. nov., are erected. The spatial distribution of the collected specimens over the Guyana Shelf was traced and the results were compared with existing information on bottom conditions. There was a convincing correlation between the location of fossil reefs and other hard substrates such as shell ridges with peaks in the occurrence of species diversity and specimen numbers. Stations made on sand and mud bottoms away from these zones of hard substrates were generally poor in species, but some were found to be rich in individuals of specialized soft bottom dwellers such as Tetilla pentatriaena, Tribrachium schmidtii, Fangophilina submersa, and Oceanapia species. The species composition of the Guyana Shelf was compared with that of neighbouring regions of the Caribbean and from North and East Brazil (Díaz in Miloslavich et al. 2010; Muricy et al. 2011). About 35% of the species encountered are widespread in the Central West Atlantic, occurring both to the north and to the south. Indications that the Guyana Shelf sponge fauna is clearly transitional are southernmost occurrences for Caribbean species (about 30%), and northernmost occurrences of Brazilian species (13%), with a high proportion (25%) of new species, which may be expected to have distributions extending to the Caribbean, to Brazil or both regions.


Assuntos
Poríferos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Brasil , Fósseis/anatomia & histologia , Guiana , Tamanho do Órgão , Poríferos/anatomia & histologia , Poríferos/crescimento & desenvolvimento
16.
J Exp Biol ; 220(Pt 6): 995-1007, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28011822

RESUMO

Sponges (Porifera) are abundant in most marine and freshwater ecosystems, and as suspension feeders they play a crucial role in filtering the water column. Their active pumping enables them to filter up to 900 times their body volume of water per hour, recycling nutrients and coupling a pelagic food supply with benthic communities. Despite the ecological importance of sponge filter feeding, little is known about how sponges control the water flow through their canal system or how much energy it costs to filter the water. Sponges have long been considered textbook examples of animals that use current-induced flow. We provide evidence that suggests that some species of demosponge do not use current-induced flow; rather, they respond behaviourally to increased ambient currents by reducing the volume of water filtered. Using a morphometric model of the canal system, we also show that filter feeding may be more energetically costly than previously thought. Measurements of volumetric flow rates and oxygen removal in five species of demosponge show that pumping rates are variable within and between species, with the more oxygen consumed the greater the volume filtered. Together, these data suggest that sponges have active control over the volume of water they process, which may be an adaptation to reduce the energetic cost of filtration in times of high stress.


Assuntos
Poríferos/fisiologia , Poríferos/ultraestrutura , Água/metabolismo , Animais , Comportamento Animal , Ecossistema , Metabolismo Energético , Filtração , Oxigênio/metabolismo , Consumo de Oxigênio , Poríferos/anatomia & histologia
17.
Zootaxa ; 4196(1): zootaxa.4196.1.3, 2016 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-27988681

RESUMO

This paper focus on the biodiversity assessment of Australian inland water. Checklists of Australian Spongillida are also provided with biogeographic notes together with the geographic range of all species of freshwater sponges in Australia. New discoveries on freshwater sponges are reported from ephemeral freshwater habitats in Kakadu National Park (Australia Northern Territory). Morphological analyses show that the sponges belong to Radiospongilla and Pectispongilla in the family Spongillidae. Radiospongilla cfr. philippinensis shows a single layer of radial gemmuloscleres and the absence of tangential gemmuloscleres in the gemmular theca. Pectispongilla gagudjuensis n. sp. diverges from the diagnostic traits of the four species currently assigned to the genus i.e. skeletal megascleres are dominant acanthostrongyles and less frequent acanthoxeas shorter than in the other species, microscleres are absent, and gemmules are larger than in the other species of the genus.


Assuntos
Poríferos/anatomia & histologia , Poríferos/classificação , Distribuição Animal , Animais , Água Doce , Northern Territory , Poríferos/fisiologia , Especificidade da Espécie
18.
Zootaxa ; 4208(6): zootaxa.4208.6.1, 2016 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-28006795

RESUMO

A series of recent expeditions in fjords and canals of Southern Chilean Patagonia allowed the re-collection of Halisarca magellanica Topsent, 1901 and the discovery of a new species, Halisarca desqueyrouxae sp. nov. The material studied was collected at depths ranging from 3 to 30 m at latitudes comprised between 42° and 49°S. Both species share the same habitat and show a morphological plasticity, but differ in their colour. Halisarca magellanica is bright pink to whitish with three morphs whereas H. desqueyrouxae sp. nov. is light brown to beige with two morphs. An extensive investigation in TEM and SEM reveals several differences among cell types with inclusions between both species. Three distinct spherulous cells occur. Type 1 is shared by both species, Type 2 is occasional in H. magellanica but absent from H. desqueyrouxae sp. nov. Type 3 is rare in H. magellanica and occurs abundantly in half of the specimens of H. desqueyrouxae sp. nov. Granular cells are shared by both species but do not occur in all specimens. Microgranular cells are characteristic of H. magellanica. Both species also clearly differ by their endobiotic bacteria. Phylogenetic analysis of cox1 sequences places H. magellanica as a sister group to all other previously published Halisarca species sequences (9.1-9.7% difference) except H. harmelini, while H. desqueyrouxae sp. nov. is placed as a sister group to H. dujardini (2.3% difference).


Assuntos
Poríferos/classificação , Animais , Chile , Ecossistema , Complexo IV da Cadeia de Transporte de Elétrons/genética , Larva/anatomia & histologia , Larva/classificação , Larva/genética , Larva/crescimento & desenvolvimento , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Filogenia , Poríferos/anatomia & histologia , Poríferos/genética , Poríferos/crescimento & desenvolvimento , Análise de Sequência de DNA
19.
Zootaxa ; 4208(4): zootaxa.4208.4.3, 2016 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-28006812

RESUMO

We used both morphological and genetic approaches to investigate and to describe a new Mediterranean sponge species of the genus Protosuberites from the estuarine-anchialine Bue Marino Cave of Sardinia (Tyrrhenian Sea). The morphotraits of the specimens were compared versus congeneric species with the strongest affinities, covering the genus geographic range worldwide. Protosuberites mereui sp. nov. is light yellow, thinly encrusting, devoid of any special ectosomal skeleton, with spicular complement of tylostyles of three size classes, single or arranged in bundles/tufts, with round to suboval heads. The new species is characterized by an exclusive diagnostic trait recorded for any cave-dwelling Protosuberites i.e. suboval and basally plated resting bodies with a foraminal aperture ornate by a collar. Resting bodies were found in the basal spongin plate firmly adhering to the substratum singly or in small groups. Also the rare, small tylostyles with a sinuous shaft and a typical mushroom-like head were never recorded in the Western Mediterranean and Atlantic species of the genus. The phylogenetic reconstruction using maximum likelihood (ML) and Bayesian Inference (BI) analyses (COI, 18S rRNA, and 28S rRNA) recovered a robustly supported sister relationship between the Mediterranean P. mereui sp. nov. and Protosuberites sp. 'Panama' from the Eastern Pacific Ocean. The genetic distances based on COI sequences between all compared Protosuberites species were always higher than 2%, a value sufficient to confirm that P. mereui sp. nov. is a distinct species within the genus. Morphological and genetic analyses confirm unanimously P. mereui sp. nov. as a new species. Our results contribute to the assessment of biodiversity in anchialine/estuarine caves and increase data on sponge adaptive strategies in these extreme ecosystems.


Assuntos
Poríferos/classificação , Poríferos/genética , Animais , Cavernas , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Itália , Microscopia Eletrônica de Varredura , Filogenia , Poríferos/anatomia & histologia , Poríferos/ultraestrutura , RNA Ribossômico 18S/genética , RNA Ribossômico 18S/metabolismo , RNA Ribossômico 28S/genética , RNA Ribossômico 28S/metabolismo , Águas Salinas , Análise de Sequência de DNA
20.
Zootaxa ; 4184(2): 386-390, 2016 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-27811648

RESUMO

Artemisina is a microcionid characterized by lacking a distinctive choanosomal skeleton or definite spongin fibres, lacking also echinating spicules, and with a nearly radial ectosomal skeleton (Hooper 2002). The genus currently has 19 valid species, six of which are recorded from the Atlantic Ocean (Van Soest et al. 2016): A. erecta Topsent, 1904, A. incrustans van Soest et al., 2013, A. melana van Soest, 1984, A. melanoides van Soest et al., 2013, A. transiens Topsent, 1890 and A. vulcani Lévi, 1963. The present study describes a new species of Artemisina from Northeastern Brazil. Four specimens of Artemisina brasili sp. nov. were collected by snorkelling at Pernambuco State. All specimens were preserved in 80% ethanol and deposited in the Porifera Collections at the Universidade Federal de Pernambuco (UFPEPOR) and Museu Nacional of Universidade Federal do Rio de Janeiro (MNRJ).


Assuntos
Poríferos/classificação , Animais , Oceano Atlântico , Brasil , Poríferos/anatomia & histologia
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