Brittle stars or ophiuroids are echinoderms and are closely related to the starfish. They crawl across the seafloor using their flexible arms for locomotion. The ophiuroids generally have five long slender, whip-like arms. The ophiuroids diverged in the early Ordivician Period, about 500 million years ago. These fossils were discovered in Morocco. ***Available in 4 sizes: $200, $250, $300, $350. Priced by size, definition of the fossil, and number of fossils on the plate so sizes will vary.