Simoniteuthis, a new vampyromorph coleoid with prey in its arms from the Early Jurassic of Luxembourg

Abstract

The evolutionary history of the cephalopod order Vampyromorpha with its only recent representative, Vampyroteuthis infernalis, the deep-sea vampire squid, is still obscure and a new specimen from the Early Jurassic of Luxembourg, provides new information on the vampyromorph morphology at this period. The new taxon Simoniteuthis michaelyi. gen. n. sp., which is based on a nearly complete gladius with associated head–arm complex, is morphologically intermediate between the families Loligosepiidae and Geopeltidae. Interestingly, the arm crown displays only four arm pairs, although an arm configuration consisting of five arm pairs should be expected in vampyromorph stem lineage representatives. This observation encouraged us to critically review the presumed homology of the filaments of Vampyroteuthis and the lost arm pair in cirrate and incirrate octopods. Moreover, two bony fishes in the mouth region implicated that Simoniteuthis michaelyi n. gen. n. sp. preyed upon them in hostile water depths, a taphonomic phenomenon called distraction sinking. By contrast to modern Vampyroteuthis infernalis, Simoniteuthis michaelyi n. gen. n. sp. roamed and hunted in shallower waters as typical for Mesozoic stem lineage vampyromorphs. According to the current fossil record, a vertical migration into deeper waters (probably associated with a shift in feeding behaviour) occurred at least since the Oligocene.