Figure 7 — The fossil starfish Urasterella asperula from the Devonian period of Germany. Photograph by Dwergenpaartje. Reproduced under CC BY-SA 3.0.
Figure 7 — The fossil starfish Urasterella asperula from the Devonian period of Germany. Photograph by Dwergenpaartje. Reproduced under CC BY-SA 3.0.