title: Adaptations to squid-style high-speed swimming in Jurassic belemnitids.
abstract: Although the calcitic hard parts of belemnites (extinct Coleoidea) are very abundant fossils, their soft parts are hardly known and their mode of life is debated. New fossils of the Jurassic belemnitid Acanthoteuthis provided supplementary anatomical data on the fins, nuchal cartilage, collar complex, statoliths, hyponome and radula. These data yielded evidence of their pelagic habitat, their nektonic habit and high swimming velocities. The new morphological characters were included in a cladistic analysis, which confirms the position of the Belemnitida in the stem of Decabrachia (Decapodiformes).
authors.affiliation: Paläontologisches Institut und Museum, Universität Zürich, Karl Schmid-Strasse 4, 8006 Zürich, Switzerland chklug@pim.uzh.ch.
authors.forename: Christian
authors.initials: C
authors.lastname: Klug
authors.affiliation: Staatliches Museum für Naturkunde, Rosenstein 1, 70191 Stuttgart, Germany.
authors.forename: Günter
authors.initials: G
authors.lastname: Schweigert
authors.affiliation: Earth and Planetary System Science, Department of Natural History Sciences, Hokkaido University, Sapporo, Japan.
authors.forename: Dirk
authors.initials: D
authors.lastname: Fuchs
authors.affiliation: Centre de Recherches sur la Paléobiodiversité et les Paléoenvironnements (CR2P, UMR 7207), Sorbonne Universités - UPMC-Paris 6, MNHN, CNRS, 4 Place Jussieu case 104, 75005, Paris, France AMNH, New York, NY 10024, USA.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Kruta
authors.affiliation: Tannenweg 16, 85134 Stammham, Germany.
authors.forename: Helmut
authors.initials: H
authors.lastname: Tischlinger
mesh_terms: D000220:Adaptation, Biological; D000818:Animals; D049830:Cephalopoda / Q000033:anatomy & histology* / Q000145:classification; D005580:Fossils; D010802:Phylogeny; D013550:Swimming
keywords: Belemnitida; Coleoidea; Decabrachia; Jurassic; nekton; phylogeny