Poriferapōrĭf´ərə [key] [Lat.,=pore bearer], animal phylum consisting of the organisms commonly called sponges. It is the only phylum of the animal subkingdom Parazoa and represents the least evolutionarily advanced group of the animal kingdom. All adult sponges are sessile (nonmotile), and nearly all are marine; there are six families of freshwater sponges. Sponges are subdivided into three classes.
Sections in this article:
- Class Hexactinellida (Glass Sponges)
- Class Demospongiae (Demosponges)
- Class Calcarea (Calcareous Sponges)
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.
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