Two worm-like organisms from the Hunsrück Slate (Lower Devonian), southern Germany
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چکیده
One radiograph of Hunsrück slate shows the presence of a drop-shaped "worm". This image resembles an acoel platyhelminth in the presence of an apparently eversible pharyngeal structure, but no trace can be tound of the complex reproductive structures of platyhelminths, making full identification impossible. Another more elongate worm-like image shows the presence of anterior perforations into a digestive tract. This feature is consistent with identification of the individual as a tunicate Chordata. Similar organisms, adjacent to the first suggest coloniality, and reinforce the identification as a tunicate. Even though this is apparently the first known Paleozoic fossil of the subphylum, the material does not warrant assignment ot a generic name.
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Morphology and ecological setting of the basal echinoid genus Rhenechinus from the early Devonian of Spain and Germany
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