A small coleoid cephalopod with soft parts from the lower Devonian discovered using radiography

Abstract

During the past 50 years, X-ray examinations have greatly increased our knowledge of fossils. Modern radiographic methods, X-ray tubes with fine focal spots, high-resolution films and optimal exposure conditions have revealed details of the anatomy and general biology of ancient life as well as species and representatives of major groups hitherto unknown in the Lower Devonian^1–5. Most of this material came from the Hunsriick slate, where most fossils are converted to pyrite, FeS₂, giving a good contrast in the radiographs. Additional image processing may reveal even more details. While screening large quantities of black slate pieces, I have discovered a small teuthid coleoid showing soft parts (Fig. 1) which is the best-preserved specimen I have found during 20 years of investigation. This Eoteuthtis elfriedae n.sp. is very similar to the living Alloteuthis africana of the Loliginidae, and is one of many unusual fossils yielded by this slate^3–5, only a few of which have been published. This specimen of E. elfridea shows that Alloteuthis-like animals have not changed much over the past 400 Myr, and means that previous concepts of the appearance of such forms must be revised.