Fossil Brittle Star - 6.00" Ophiurida
Fossil Brittle Star - 6.00" Ophiurida
Brittle Stars are one of the oldest groups of animals in the fossil record. Their whip-like arms and star shaped bodies have remained relatively unchanged through hundreds of millions of years, which is a testament to their evolutionary success.
This specimen is a 6.00" Ordovician Ophiurida Brittle Star, which lived over 440 million years ago. Members of the genus could be found all over the world and resembled modern brittle stars in shape and behavior. This particular starfish comes from the Ktaoua Formation in Morocco.
📸 The fine detail of a fossilized Brittle star
Fossil Brittle star
The Brittle Star is a frightening relative of the starfish. Unlike their slower cousins, brittle stars use their whip-like arms to crawl across the ocean floor and capture prey. This specimen is an Ordovician Ophiurida Brittle Star, which lived over 440 million years ago. Members of the genus could be found all over the world and resembled modern brittle stars in shape and behavior. These starfish come from the Ktaoua Formation fossil beds in Morocco.
📸 A Sample Fossil Brittle Star Plate
Ophiurida brittle stars lived their whole lives on the ocean floor. Upon their death, they were covered in loose sediments and fossilized over the course of millions of years. This fossil is an imprint of one such brittle star.
This specimen is a one-of-a-kind fossil brittle star which comes with a a stand for display. An informational card that serves as a certificate of authenticity is also included.
Each of these fossil starfish is a unique item and sold by size. You can see all of our starfish at the collection below!
MORE ABOUT BRITTLE STARS
ESTIMATED AGE : c. 480,000,000 years old
Optimized Radial Symmetry
There is a tendency to expect massive changes in the shape and structure of organisms over the course of evolution. But under the sea, there are patterns that play themselves out over and over again across the millennia.
Consider radial symmetry, where an organism spawns off identical pieces of itself around a central node, like a flower’s petals center around its pistil. One particular type of marine invertebrate uses this anatomical structure to its advantage: the brittle star.
An Evolutionary Predator
The brittle star is a feat of evolutionary engineering. Its digestive, nervous, and reproductive systems are all concentrated in its central disk, allowing for its arms to be lost and regenerated without concern. The brittle star uses this to its advantage to avoid predation, shedding one of its arms so it can make its escape. Often in a given population, over half of brittle stars will be in the process of regenerating a lost limb.
Unlike their sea star cousins , brittle stars’ long flexible arms allow them to scurry across the ocean floor. These arms are more slender than their cousins, but are reinforced with a layer of calcium carbonate-based scales to protect them from predators. Most brittle stars are bottom feeders, filtering sediment or water for organic material, but their quick movements allow some to be apt hunters.
Fossilization and Deep Time
Brittle stars have adapted to many different environments across the world, from arctic waters to the roiling heat of hydrothermal vents. They were one of the first deep-sea animals to be discovered and documented, when in 1818 Sir John Ross dredged up a Gorgonocephalus caputmedusae while depth-sounding off Greenland.
This brittle stars' scientific name is Ophiuroidea, of the Echinoderm phylum. Within its class are at least 2,064 species, but this particular specimen is an Ordovician Ophiurida which lived over 440 million years ago. It comes from the Katoua formation, a geological formation in Morocco from the Ordovician era.
When looking at a brittle star fossil today, it is quite easy to see how similar they were to modern specimens. This is a testament to the group's staying power. Brittle stars have been around since long before the dinosaurs, and have long outlived them as well. They survived all six mass extinctions since the Cambrian with a relatively consistent body structure throughout. Though we may think of them as small and slow creatures, they are actually highly adaptable and highly successful through much of deep time.
Front of the Specimen Card
Back of the Specimen Card
Astley, Henry C. “Getting Around When You’re Round: Quantitative Analysis of the Locomotion of the Blunt-Spined Brittle Star, Ophiocoma Echinata.” Journal of Experimental Biology 215.Pt 11 (2012): 1923–1929. Web.
Bobbe, S. (2016, March 30). Arctic Wildlife: Get to Know Brittle Stars. Ocean Conservancy. Retrieved October 27, 2022
O’Hara, Timothy D. et al. “Restructuring Higher Taxonomy Using Broad-Scale Phylogenomics: The Living Ophiuroidea.” Molecular Phylogenetics and Evolution 107 (2017): 415–430. Web.
Pechenik JA. Biology of the Invertebrates. Seventh edition. McGraw-Hill Education; 2015.
Stöhr, Sabine, Timothy D O’Hara, and Ben Thuy. “Global Diversity of Brittle Stars (Echinodermata: Ophiuroidea).” PloS one 7.3 (2012): e31940–e31940. Web.