megasclere

zoology

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June 30, 2026

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A megasclere is a large spicule, specifically one of the skeletal spicules found in sponges. Sponges are primitive aquatic invertebrate animals that filter feed by drawing water through a system of canals and chambers. Their skeletons, which are taxonomically significant, can be mineral (calcareous or siliceous) or composed of spongin.123

Spicules are classified into two main types: megascleres, which provide support, and microscleres, which offer protection and also aid in support. The specific forms and compositions of these spicules vary among the different classes of sponges.32

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sponge
Mineral skeletons
…siliceous spicules, consisting of both megascleres and microscleres, of the Demospongiae have an enormous variety of forms. The megascleres may be monaxons with both ends pointed (oxeas), with one end pointed and the other rounded (styles), or with both ends rounded (strongyles). If one end is swollen styles are called…
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…siliceous spicules, consisting of both megascleres and microscleres, of the Demospongiae have an enormous variety of forms. The megascleres may be monaxons with both ends pointed (oxeas), with one end pointed and the other rounded (styles), or with both ends rounded (strongyles). If one end is swollen styles are called…
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