Ophiomusa is a genus of echinoderms, which includes sea urchins, sand dollars and sea cucumbers, belonging to the family Ophiolepididae. Ophiurida are similar to starfish; they both have a central disc and five arms sprouting from the disc. One of the main distinguishing factors of an Ophiuroid is its arms; the arms of an Ophiurida are longer, thinner, and distinctly separated in comparison to those of a sea star.

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