Klug Christian, Schweigert Günter, Fuchs Dirk, Kruta Isabelle, Tischlinger Helmut
Paläontologisches Institut und Museum, Universität Zürich, Karl Schmid-Strasse 4, 8006 Zürich, Switzerland
Staatliches Museum für Naturkunde, Rosenstein 1, 70191 Stuttgart, Germany.
Biol Lett. 2016 Jan;12(1):20150877. doi: 10.1098/rsbl.2015.0877.
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).
虽然箭石（已灭绝的头足纲）的钙质硬体部分是非常丰富的化石，但它们的软体部分却鲜为人知，其生活方式也存在争议。侏罗纪箭石类的新化石——棘乌贼，提供了关于鳍、颈部软骨、项圈复合体、平衡石、水管和齿舌的补充解剖学数据。这些数据证明了它们的远洋栖息地、游泳生物习性和高游泳速度。新的形态特征被纳入分支系统学分析，这证实了箭石目在十腕总目（十足目）演化支中的位置。
