A unilaterally polished sea urchin of the species Pygurus marmonti.
Age: 157 million years; Upper Jurassic / Oxfordian
Locality: Sakahara, Madagascar
Size approx.:7cm
Sea urchins are echinoderms and their fossil record dates back to the Ordovician period. This fossil of a flattened and bilaterally symmetrical sea urchin of the species Pygurus marmonti comes from the vicinity of the village of Sakahara, Madagascar. The age is determined to be approximately 157 million years. The fossil is unilaterally polished. The structure of the body (skeleton) of the urchin is clearly visible on the polished surface.
