500-million-year-old trilobite fossils reveal never-before-seen details

We owe one of the most remarkable momentary fossils ever seen to a thermal shock. A trilobite was hunting for small invertebrates in shallow water when its “sky”—the surface of the water—suddenly darkened. A fiery cloud had just covered the sea, and very quickly, this Cambrian arthropod had to absorb more and more fine particles of burning ash. Suffocated, it remained embedded in the hot, compact mass for 515 million years, in what became the Tatlet geological formation in Morocco.

Under the supervision of geologist Abderrazak Albani, from the University of Poitiers, an international team was able to bring to light a number of trilobite specimens, which they photographed in detail in order to reveal “unprecedented details”. Everything is there: the glabella and the glabrous regions that make up the cephalon (head), the fine structure of the culmen (the grinding part of the mouth), the fine bristles of the multiple legs, the tiny antennae, every single one of the many parts, the digestive system, the stomach and its glands, and even the internal soft tissues…

Other details that were never well revealed are: Healingled to the definition of two new species (about 22,000 species are already known!). The possibility of studying this type of lip that forms part of the centaur correctly constitutes an important discovery in paleontology, since the trilobite lineage is largely based on the structure of their mouths.

However, there is another detail that makes the mouth of the trilobite Tattle interesting: it was inhabited! Brachiopods, small animals with shells equipped with valves, settled near some of the trilobites, to enjoy their meals! This amazing symbiosis had never been observed before, and it had several aspects, as other brachiopods were attached to the shield. It is a symbiosis that has so far eluded paleontologists.

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