The World’s longest death track: The last footsteps of an ancient horseshoe crab

Dean R Lomax (UK) A ‘big’ discovery In 2002, a wonderful discovery of a 9.7m-long trackway (ichnofossil) with the tracemaker (a horseshoe crab) preserved was made in a quarry near the village of Wintershof, north of the town of Eichstätt in Bavaria, Southern Germany (Fig. 1). Specifically, the specimen was collected from the Solnhofen Lithographic Limestones, Eichstätt Formation (Solnhofen Group), Hybonotum Zone, Riedense Subzone from the Late Jurassic (Tithonian). Fossils from Eichstätt are often confusingly thought to be from the area of ‘Solnhofen’, with the Solnhofen area being a world renowned Lagerstätte. Many exceptionally well-preserved fossil specimens have been collected from that area, including the famous fossils of Archaeopteryx. Fig. 1. Locality map of the fossil bearing localities within the Solnhofen area. Note the areas of Eichstätt and Wintershof, the locality of the trackway (WDC CSG-233). (Reproduced from Lomax and Racay, 2012.) However, many people are unaware that there are numerous localities that surround the area of Solnhofen, which yield many of the fossils from this famous geological unit. It has been suggested that several of the fossils found within the rocks originally laid down in the Solnhofen lagoons (which were part of an archipelago) are the result of mass storm events, during which organisms from the nearby Tethys Ocean were thrust into these anoxic lagoons during heavy storms. In many cases this was the beginning of the end. The horseshoe crab that produced this trackway was identified as Mesolimulus walchi. The taxon is fairly well recorded within the limestones … Read More