Michael Ramming‡, D. Korn§, Carina Klein‡, Christian Klug|© Michael Ramming, D. Korn, Carina Klein, Christian Klug. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Citation:
Ramming M, Korn D, Klein C, Klug C (2018) Morphology of the Early Jurassic Arietitidae and the effects of syn vivo serpulid infestations. Fossil Record 21(1): 67-77. https://doi.org/10.5194/fr-21-67-2018 |  |
Selected specimens from the Jurassic ammonoid family Arietitidae wereinvestigated using morphometric methods of transverse and longitudinal conchsection analysis. The family Arietitidae is characterized by similarities inthe conch geometry, but variation can be demonstrated by means ofdifferences in conch morphology. Our study focuses on a specimen of thearietitid Pararnioceras sp., which revealed striking changes inconch morphology due to a syn vivo growth through a parasitic serpulid.Changes in its ontogenetic development are compared with specimens withoutepizoans. The ecological interpretation of the morphometric data allows theconclusion that the host possessed the ability to counteract the parasiticconch abnormalities by adapting its housing growth, thus ensuringsurvival.