Starfish & Brittle Star Fossils For Sale

Starfish are echinoderms of the order Asteroidea. They first appeared in the fossil record during the Ordovician about 450 million years ago. Brittle Stars are closely related to starfish and appeared in the fossil record around the same time. Starfish and brittle star fossils are not common, since both disintegrate quickly after death.

Ordovician Brittle Star (Ophiura) - Morocco #286673

1.1" Ordovician Brittle Star (Ophiura) - Morocco

$25

20 days ago

Ordovician Brittle Star (Ophiura) - Morocco #286674

.85" Ordovician Brittle Star (Ophiura) - Morocco

$22

20 days ago

What Is A Starfish?

Starfish (sea stars) are echinoderms of the order Asteroidea. They are marine dwelling organisms that can have anywhere from three to forty arms, but most have five to seven. They move by using hundreds of suction feet to crawl across the seafloor, preying on crustaceans and small invertebrates.

What Is A Brittle Star?

Brittle stars are echinoderms of the class Ophiuroidea. They are marine dwellers with five arms around a central body disk. They move by using their flexible arms to crawl along the bottom and, in some cases, swim short distances.

What Is The Difference Between Starfish And Brittle Stars?

Starfish and brittle stars are closely related but they have seveal notable differences. Starfish have anywhere from three to forty arms, while brittle stars only have five. Starfish thearms blend together into the central body, while brittle star arms attach to a well-defined central disk. Both have calcite ossicles that form a skeleton-like structure. In starfish these ossicles are fused together, while in brittle stars they are independent, allowing a greater range of motion.

When Do Starfish And Brittle Stars First Appear?

Both brittle stars and starfish appear about the same time in the fossil record about 450 million years ago during the Ordovician Period.

When Do Brittle Stars And Starfish Die Out?

Both starfish and brittle stars are still living today. About 2,000 species each of brittle star and starfish inhabit the world's oceans. The diversity of species declined during the Devonian and Permian Extinctions, but expanded significantly during the Early Jurassic.

Where Are Starfish And Brittle Star Fossils Found?

Starfish and Brittle Star fossils are uncommon. As the body decomposes around the ossicles, they tend to fall apart and disperse. A few formations are well known for their fossils, including the Jurassic Solnhofen Limestone in Germany, Middle Cretaceous formations in Lebanon, some of the Ordovician formations in Southern Morocco, and some of the Ordovician formations in Ontario.

STARFISH & BRITTLE STAR FOSSILS FOR SALE