155-Million-Year-Old Brittle Star Fossil Reveals Ancient Clonal Reproduction

Exceptionally preserved specimen from Germany provides rare evidence of fissiparity in Jurassic echinoderms.

The fossil, named Ophiactis hex, was found in a limestone deposit in southern Germany.
It shows the brittle star in the middle of regenerating half its body, a process known as clonal fragmentation.
This discovery pushes back the known evolutionary history of fissiparity to at least 155 million years ago.
The fossil's six-armed structure supports theories linking clonal fragmentation to sixfold symmetry.
Researchers highlight the rarity of finding such fossils, which offer valuable insights into ancient reproductive strategies.