1. Aix Marseille University, CNRS, LCB Marseille 13402 France
2. International Associated Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms (LIA‐MagMC), CNRS‐CAS Marseille 13402 France
3. Microscopy Core Facility, FR3479 IMM, CNRS, Aix Marseille University Marseille France
4. Sorbonne Université, UMR CNRS 7590, Muséum National d'Histoire Naturelle, IRD, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC 75005 Paris France
5. CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences Qingdao 266071 China
6. Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences Beijing 100029 China