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Cribricyatha
Cribricyatha is an extinct class of sponge-like animals which lived in the early to mid-Cambrian Period ( Tommotian to Botomian). Description Cribricyatha were cup-shaped filter feeders similar to archaeocyathan sponges, with a skeleton composed of magnesium-rich calcite microgranules. The base is narrow, broadening upwards into a solid conical or semi-conical shell. In horizontal cross-section, the cup may be circular, elliptical, cardioid (heart-shaped), or quadrate (square-shaped).''Treatise on Invertebrate Paleontology'' Part E, Revised. Porifera, Volumes 4 & 5: Hypercalcified Porifera, Paleozoic Stromatoporoidea & Archaeocyatha, liii + 1223 p., 665 figs., 2015, availablhere . All cribricyaths can be characterized by a series of peripterates, ribbon-like crests ringing around the outer surface of the shell. In cribricyaths of the order Cribricyathida, the peripterates may be supplemented by baculi, low ridges running parallel to the main shaft of the shell. Internally, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sponge
Sponges or sea sponges are primarily marine invertebrates of the animal phylum Porifera (; meaning 'pore bearer'), a basal clade and a sister taxon of the diploblasts. They are sessile filter feeders that are bound to the seabed, and are one of the most ancient members of macrobenthos, with many historical species being important reef-building organisms. Sponges are multicellular organisms consisting of jelly-like mesohyl sandwiched between two thin layers of cells, and usually have tube-like bodies full of pores and channels that allow water to circulate through them. They have unspecialized cells that can transform into other types and that often migrate between the main cell layers and the mesohyl in the process. They do not have complex nervous, digestive or circulatory systems. Instead, most rely on maintaining a constant water flow through their bodies to obtain food and oxygen and to remove wastes, usually via flagella movements of the so-called " collar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
