Original paper

Tonneleryon, a new gregarious polychelidan lobster from the early Toarcian Posidonia Shale of Holzmaden (Germany)

Audo, Denis

Abstract

Polychelidan lobsters are decapod crustaceans characterized by a peculiar morphology: four to five pairs of claws and a flattened body. They were first discovered as fossils long before being discovered in modern deep sea environments. Many aspects of fossil and extant polychelidan biodi- versity and ecology still remain poorly understood. This paper documents a new species and genus of polychelidan lobster, Tonneleryon schweigerti n. gen., n. sp. from the Toarcian of Holzmaden (Baden Württemberg, Germany). It also re-describes ?Coleia sinuata Beurlen, 1928, which was confused until now with the new species. Actually, ?Coleia sinuata was described on the basis of a single, poorly preserved, juvenile specimen. Tonneleryon schweigerti is characterized by large eyes, which suggest its vision played an important role in its life-habits. Specimens of Tonneleryon schweigerti are generally preserved in cluster of several individuals, a characteristic unique to this species. All specimens in these accumulation are of similar size and do not possess the characteristics of exuviae such as a split median line or disjunction of carapace and first pleonite. They therefore probably represent a mass-mortality assemblage and suggest this species was gregarious.

Keywords

polychelidamass mortalityholzmadenhypertrophied eyespalaeobiologygermany