Paleontologists have uncovered two new species of aculiferan mollusks that lived during the Silurian period, approximately 430 million years ago. The discovery reveals that early mollusks were more complex and adaptable than previously thought.
The newly discovered species, Punk ferox and Emo vorticaudum, were found in fossil deposits in Herefordshire, England. They feature distinctive spikes and other unique characteristics that set them apart from earlier described early mollusk species.
According to Dr. Mark Sutton, a paleontologist at Imperial College London, “Mollusks are one of the largest and most diverse animal groups on Earth.” However, early aculiferan mollusks have received limited attention, with previous assumptions suggesting they were basic and simple.
To gain insight into these ancient creatures, researchers employed two methods. They used X-ray scanning to examine internal structures without damaging the fossils, while also carefully grinding down the fossils in thin layers to create 3D images of their external features.
The analysis revealed that both fossils had smooth undersides, indicating they lived on the sea floor. The Emo vorticaudum fossil was found in a folded posture, suggesting it moved like an inchworm using its spines to grip and push forward. In contrast, the movement of Punk ferox remains unclear, with researchers finding it had a ridge-like foot unlike any existing mollusk.
The discovery not only sheds new light on the evolutionary history of mollusks but also challenges previous assumptions about their complexity and diversity. The study’s findings were published in the journal Nature.
Source: https://www.sci.news/paleontology/silurian-aculiferan-mollusks-13568.html