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Hypercalcified demosponges and the end-Permian extinction
Global and Planetary Change, 2010Abstract The hypothesis is presented here that the hypercalcified demosponges, characterized by a solid, largely external skeleton of spherulitic aragonite, or of high-Mg calcite, had symbiotic cyanobacteria, from the outset of their existence, that enabled them to precipitate their peculiar skeleton, and that both the skeleton and the cyanobacteria ...
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Chemotaxonomic study of the demosponge Cinachyrella cavernosa (Lamarck)
Biochemical Systematics and Ecology, 2015Sterols as acetates and phthalate esters were identified by GC–MS in demosponge Cinachyrella cavernosa. The sponge contained mainly C27, C28 and C29 Δ5 conventional sterols and minor amounts of C27 and C28 Δ0 analogues. This study also reports the presence of an ester, clionasterol oleate, 16-dehydropregnenolone (DPA), relatively rare cyclopropane ...
Solimabi Wahidullah +2 more
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Some aspects of silica deposition in lithistid demosponge desmas
Microscopy Research and Technique, 2003AbstractTransmitted light microscope and SEM observations of various growth stages, including very young forms, of lithistid demosponge spicules called desmas provided a wealth of new observations on silica deposition in desmas of most lithistid demosponge groups.
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Demosponge Higher Taxa Classification Re-Examined
1991Thirty-five years ago the foundation was laid for a classification of the Demonspongiae that in essence is still in use among virtually all neontologists. I am referring to Levi’s (1953) system based on reproductive characters. Unfortunately, when examined closely, this scheme of classification cannot endure a test of logical consistence.
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Comparative study of spiculogenesis in demosponge and hexactinellid larvae
Microscopy Research and Technique, 2003AbstractSpicule deposition was studied by electron microscopy in fixed embryos and larvae of the haplosclerid sponge Reniera sp. and the hexactinellid Oopsacas minuta. Spicules form in centrally located vacuoles within cells and within syncytia, as in the adult sponges. In Reniera, scleroblasts differentiate from micromeres prior to gastrulation.
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Non-Spicular Biomineralization in Calcified Demosponges
1991The sponges occupy an unusual evolutionary position as the most primitive of metazoans. However, despite their relatively small number of cell types they have evolved a considerable array of morphological forms and have evolved into a variety of ecological habitats.
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Feeding in deep-sea demosponges: Influence of abiotic and biotic factors
, 2017L. M. Robertson, J. Hamel, A. Mercier
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Studio comparativo dell'accumulo microbiologico in due demosponge mediterranee
2008The microbiological accumulation capability in the demosponges Spongia (Spongia) officinalis and Oceanapia isodictyiformis of six microbiological parameters were studied in the water and in sponge samples coming from Porto Cesareo (Northern Ionian Sea).
Longo C +4 more
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