“Before this, there had been nothing found on the Iberian Peninsula in the Ordovician that even resembled these,” Kimmig said. “They close a gap in time and space. And what’s very interesting is the kind of fossils. We find Medusozoa — a jellyfish — as well as animals which appear to be wiwaxiids, which are sluglike armored mollusks that have big spines. We found these lateral sclerites of animals which were actually thought to have gone extinct in the late Cambrian. There might have been some that survived into the Ordovician in a Morocco deposit, but nothing concrete has been ever published on those. And here we have evidence for the first ones actually in the middle of the Ordovician, so it extends the range of these animals incredibly.”
Kimmig said the discovery of uncommon wiwaxiids fossils in this time frame suggests the animals lived on Earth for a far greater span of time than previously understood.
“Especially with animals that are fairly rare that we don’t have nowadays like wiwaxiids, it’s quite nice to see they lived longer than we ever thought,” he said. “Closely after this deposit, in the Upper Ordovician, we actually get a big extinction event. So, it’s likely the wiwaxiids survived up to that big extinction event and didn’t go extinct earlier due to other circumstances. But it might have been whatever caused the big Ordovician extinction event killed them off, too.”Paper. (paywall) – Julien Kimmig, Helena Couto, Wade W. Leibach, Bruce S. Lieberman. Soft-bodied fossils from the upper Valongo Formation (Middle Ordovician: Dapingian-Darriwilian) of northern Portugal. The Science of Nature, 2019; 106 (5-6) DOI: 10.1007/s00114-019-1623-z More.
They are naturally hoping for more fossils. Extinction, generally, seems to take longer than we sometimes suppose.
See also: Ars Technica: Ars Technica: Ordovician Period “Even Crazier” Than The Cambrian
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