最近、吸盤の化石記録についてのレビュー論文が出たのでメモしておく．古生物学は専門ではなくなかなか先行研究を追えていないので，とても参考になりそう．
リファレンス
Evolutionary development of the cephalopod arm armature: a review.
Fuchs, D., Hoffmann, R. & Klug, C. 2021. Swiss J Palaeontol 140, 27.
https://doi.org/10.1186/s13358-021-00241-z
要旨
The cephalopod arm armature is certainly one of the most important morphological innovations responsible for the evolutionary success of the Cephalopoda. New palaeontological discoveries in the recent past afford to review and reassess origin and homology of suckers, sucker rings, hooks, and cirri. Since a priori character state reconstructions are still ambiguous, we suggest and discuss three different evolutionary scenarios. Each of them is based on the following assumptions: (1) Neocoleoidea uniting extant Decabrachia and Octobrachia is monophyletic (= proostracum-bearing coleoids); (2) extinct Belemnitida and Diplobelida are stem decabrachians; (3) proostracum-less coleoids (Hematitida, Donovaniconida, Aulacoceratida) represent stem-neocoleoids; (4) Ammonoidea and Bactritoidea are stem coleoids. We consider a scenario where belemnoid hooks derived from primitive suckers as well-supported. Regarding belemnoid hooks and suckers as homologues implies that belemnoid, oegopsid, and probably ammonoid arm hooks arose through parallel evolution. Our conclusions challenge the widespread opinion, whereupon belemnoid hooks evolved de novo, and instead support earlier ideas formulated by Sigurd von Boletzky.
このレビューの中で引用されている論文で、ベレムナイトの軟体部の化石に関する報告で見落としていた重要なものがあったのでこちらも控えておく．鉤爪だけでなく吸盤らしきものもしっかり見えている．この化石はすごい．こういうの生で見てみたいなぁ．
リファレンス
New evidence of functional suckers in belemnoid coleoids (Cephalopoda) weakens support for the ‘Neocoleoidea’ concept.
Fuchs, D., von Boletzky, S., & Tischlinger, H. 2010. Journal of Molluscan Studies, 76(4), 404-406.
https://doi.org/10.1093/mollus/eyq032
