Hi everybody. I stumbled upon those photos on another forum and i wondered about what are they, and about how and "who" made those alignaments of aptychi. They've been found in Valanginian marls, Saynoceras verrucosum zone.
Concerning what and how, the authors of that article Double alignments of ammonoid aptychi from the Lower Cretaceous of Southeast France proposed several hypothesis : a possible bottom current ; regurgitalites of an ammonoid eater ; stomachal residues ; cololites. But their best hypothesis is cylindrical coprolites that separated in two parts just after the animal defecated or being close to the sea bottom or in relation to the anatomy of the anus or the cloaca. As to who, the candidates could be teleost fishes, plesiosaurs, ichthyosaurs, marine turtles, crocodiles.
I'm very curious about those alignments of aptychi and wondered if one of you has seen something similar to this or could have an idea about the animal that produced them ?
Thank you for your participation.
Cheers,
Sophie.