Ancient "Giant" Marine Worm Fossils Unearthed in Morocco’s 455-Million-Year-Old Rocks

Paleoscolelid worms lived in all seas, but there is evidence of the presence of their fossils only in a tiny part of the Moroccan site. According to the UCM and IGEO paleontologist, Juan Carlos Gutiérrez Marco, this discovery is a "paleontological surprise in a geological context that is not at all favorable", especially since the fossils of these marine worms were well preserved in shales, fine-grained rocks.

The preservation of these marine worms was favored by rapid burial after protection under bacterial veils that precipitate iron sulfides. Their skin was covered with phosphatic microsclerites (20 to 100 thousandths of a millimeter), arranged in an annular way in successive segments, as can be read in the journal Historical Biology.

The two marine worms discovered add to the worm Gamascolex vanroyi, found a few years ago at the same site and by the same research group, reports The Objective. The researchers also revealed the size of the three worms, which is two to three times greater than the world record for paleoscolelids in Australia, North America or Central-Western Europe.

This fact could be related to the metabolic causes of "polar gigantism", given that Morocco was located in the Ordovician, very close to the South Pole of the Earth, explains Gutiérrez Marco. "We are trying to reconstruct the ecosystems and organisms of the past, and the data obtained in this case help to refine the geological correlation of the fossiliferous units of Morocco with other contemporary ones located on the marine platform of the disappeared continent of Gondwana," he adds.