The record of Avetoichnus luisaeuchman & Ratazzi, 2011 in the Iberian Peninsula: facies relations and palaeoenvironmental implications

Abstract

Recently, the new ichnogenus Avetoichnus and the corresponding type ichnospecies Avetoichnus luisae Uchman & Ratazzi, 2011 were defined mainly based on Cenozoic specimens from deep-sea sediments from the Alpine realm (Italy and Poland). Avetoichnus luisae is a complex trace fossil, horizontal or subhorizontal, with a helical spiral string around a simple, straight or slightly curved core. The structure is interpreted as a non-graphoglyptid agrichnion generated probably by polychaetes, and less probably by enteropneusts. Here, complementary occurrences in Palaeocene and Eocene sediments from the North of Spain (Zumaia and Gorrondatxe sections), representing the record of this ichnoespecies in the Iberian Peninsula, are described. The studied specimens reveal a narrow relationship with deep-sea settings, characterized by moderately oligotrophic conditions, during relatively high sea-levels, inducing a microbial gardening behaviour of the producer. Obtained data and interpretations corroborate and complement the characterization and interpretation of the recently defined ichnotaxa