One of the world's most important fossils found in Powys

Dr Lucy Muir said the discovery was important because it gives a new insight into how life was evolving at this time. Credit: PA Images

One of the world’s most important fossil deposits has been found in Wales, experts have claimed.

The "extraordinary" new fossils, including many soft-bodied creatures, were discovered near Llandrindod Wells in Powys.

Amgueddfa Cymru – Museum Wales researchers said the fossils were in rocks that were laid down under the sea more than 460 million years ago. At that time, mid Wales was was covered by an ocean.

It follows the discovery of more than 170 species during the Covid-19 lockdowns at a secret location on private land known as Castle Bank.

The new fossils also include many different types of worms, sponges, barnacles, starfish and a primitive horseshoe crab. Credit: PA Images

Very fine details can be seen on many of the fossils under the microscope, including eyes and possible primitive brain in the head of an unknown arthropod, gut traces in trilobites and other animals, and worm tentacles and jaws.

Researchers and Llandrindod residents Dr Joseph Botting and Dr Lucy Muir said it was one of the very rare sites where soft tissues and complete organisms are preserved, rather than just hard parts like shells and bones.

Almost all the previous examples are from the Cambrian Period but Castle Bank dates from the Middle Ordovician, some 50 million years later.

Dr Muir said it "coincides with the ‘Great Ordovician Biodiversification Event’, when animals with hard skeletons were evolving rapidly".

She added: “For the first time, we will be able to see what the rest of the ecosystem was doing as well.”

This is one of the species of tiny bivalved arthropod with long grasping appendages that has been found in Powys. Credit: PA Images

Fossils of many different kinds of animals were found at Castle Bank and most were small – between 1mm to 5mm – and many were either completely soft-bodied when alive or had a tough skin or exoskeleton.

Places where such soft-bodied fossils are found are extremely rare, and only one other Ordovician site in the world, the Fezouata Biota of Morocco, preserves close to this level of detail.

The Castle Bank fossils include the youngest known examples of some unusual groups of animals, including opabiniids with their vacuum cleaner-like proboscis, and wiwaxiids, strange oval-shaped molluscs with a soft underbelly and a back covered with rows of leaf-shaped scales and long spines.

“In some ways this is a real community effort to reveal this fauna, because it wouldn’t have been possible for us to do it without the support of a large number of people,” said Dr Botting.

“Even most universities do not have the equipment that we were ultimately able to buy.”

Dr Botting and Dr Muir have spent over 100 days in the field collecting the fossils and are working with colleagues in Cardiff, Cambridge, Sweden and China to examine the finds.

“There are some very important early Ordovician fossil sites but those are from much earlier, and entirely soft-bodied animals are rare even there,” said Dr Botting.

“Here, it seems, we’ve got everything. Despite the extraordinary range of fossils already discovered, work has barely begun.

“Every time we go back, we find something new, and sometimes it’s something truly extraordinary. There are a lot of unanswered questions, and this site is going to keep producing new discoveries for decades.

“This is just the beginning, and we’re excited to see what comes next.”

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