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Microstructural characacterization of shell components in the mollusc Physa sp.

Silvia M de Paula·Marina Silveira
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Abstract

Shells of the freshwater, pulmonate snail Physa (Mollusca, Gasteropoda), ranging from 0.5 to 10 mm in length, were studied using scanning microscopy, x-ray analysis, and infrared spectroscopy. Results obtained suggest that the shell is composed of aragonite, which occurs in several distinct crystalline forms. A selective distribution of crystalline forms (hexagonal plates, prisms, rhombohedra, and spherulites) occurred along specific sites of the shell. A variable distribution of the forms was also detected in adult shells and in protoconchs of developing embryos. Qualitative elemental analysis, using an energy-dispersive spectrometer, corroborates the presence of calcium, phosphorus and sulphur ions.

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AnimalsCalciumCalcium CarbonateCrystallizationMicroscopy, Electron, ScanningMolluscaPhosphorusSpectroscopy, Fourier Transform InfraredSulfurX-Ray DiffractionJournal ArticleResearch Support, Non-U.S. Gov't

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Silvia M de Paula, Marina Silveira. Microstructural characacterization of shell components in the mollusc Physa sp.. https://doi.org/10.1002/sca.4950270303

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