|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||Age range and collections|
Ophiuroidea - Oegophiurida - Protasteridae
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If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.
|F. H. C. Hotchkiss 1993||Carinal spines begin near the periphery of the disc; there are approximately 1 3 spines in the space of four ambulacrals. The carinal spines are not preserved in a rigid erect position; instead they are recumbent, usually all leaning in the same direction, and certainly not fused to the upper arm plates. The splay of the uppermost vertical spines nearly doubles the overall arm width so that it nearly equals the disc radius. The disc tends to have convex interradii, lacks spines, and is covered above and below by minute granules which conceal underlying plates.|