One worm in three substrates: Neoichnological analyses of u-shape structures in the Golfo Nuevo Beaches, Patagonia, Argentina

Abstract

Neoichnology is an actualistic view of how organisms are connected with theplace where they live, providing modern models and ideas that serve as analogous.At Chubut province (Patagonia), in the Golfo Nuevo beaches lives a polychaetethat inhabits at the same time in rocky abrasion platforms and sandy intertidalsediments. The traces made by the worm can be compared with Caulostrepsislikein hard substrates while in soft-sediments are comparable with Skolithos-Arenicolites- like structures. The worm builds a “chimney” over the substrate, thatcan be removed by tidal activity, and incorporated into the surroundings as an“ichnoclast”. The present short note is intended to describe this occurrence anddiscuss its importance to ichnology.