Euchericherata A large group of arthropods that includes horseshoe crabs, scorpions, spiders, mites, ticks, and the extinct sea scorpions and snails. Abundant cetapedites The new species of Euchelycerate, which lived in what is now Morocco during the Early Ordovician period 478 million years ago, bridges the gap between modern and Cambrian species.
“Modern scorpions, spiders, and horseshoe crabs belong to a vast lineage of arthropods that appeared on Earth about 540 million years ago,'' said Lorenzo Lustri, a paleontologist at the University of Lausanne. Ta.
“More precisely, they belong to the subphylum, chelicerates, which includes organisms equipped with pincers used specifically for biting, grasping prey, and injecting venom, and therefore chelicerates ( Euchelicerata+Pycnogonida). But what is the ancestor of this very special group?
“This question has puzzled paleontologists ever since the study of ancient fossils began.”
“Among early arthropods, it has been impossible to identify with certainty which forms share enough similarities with modern species to be considered ancestral.”
“The mystery is further complicated by the dearth of available fossils from the critical period between 505 million and 430 million years ago. This has made genealogical research easier. must.”
Abundant cetapedites. Image credit: Lustri other., doi: 10.1038/s41467-024-48013-w.
Dr. Rustri and his co-authors collected fossils of euchelicerate from the 478-million-year-old Fezouata Shale in Morocco, and found that the modern-day euchelicerate and the Cambrian (505 million-year-old) We identified a new species that binds the eucheris cerate.
with scientific name Abundant cetapeditesthe body length of this species was 0.5-1 cm.
“This animal makes it possible for the first time to trace the entire lineage of Euchelicerates, from the appearance of early arthropods to modern spiders, scorpions and horseshoe crabs,” Dr Rustri said.
“Initially, we just wanted to describe this fossil and give it a name.”
“I had no idea it would hold so many secrets.”
“It was therefore an exciting surprise to discover, after careful observation and analysis, that it also fills an important gap in the evolutionary tree of life.”
“Yet, this fossil has not yet revealed all its secrets,” he added.
“Indeed, some of its anatomical features allow for a deeper understanding of the early evolution of the eucherycerate group and perhaps link other fossil forms to this group, the similarities of which are still hotly debated. It is even possible.”
of result appear in the diary nature communications.
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L. Rustri other. 2024. Late Ordovician syndiphosrines reveal the diversity and evolution of early euchelicerates. Nat Commune 15, 3808; doi: 10.1038/s41467-024-48013-w
Source: www.sci.news
