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Crinozoa
echinoderm subphylum
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annotated classification
- In echinoderm: Annotated classification
Subphylum Crinozoa Both fossil and living forms (Lower Ordovician about 500,000,000 years ago to Recent); with 5-part symmetry; soft parts enclosed in theca, which gives rise to 5 or more complex feeding arms. Class Crinoidea (sea lilies and feather stars) Lower Ordovician about 500,000,000 years ago…
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