Premium
The coarse wrinkle layer of P alaeozoic ammonoids: new evidence from the E arly C arboniferous of M orocco
Author(s) -
Korn Dieter,
Klug Christian,
Mapes Royal H.
Publication year - 2014
Publication title -
palaeontology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.69
H-Index - 63
eISSN - 1475-4983
pISSN - 0031-0239
DOI - 10.1111/pala.12087
Subject(s) - wrinkle , shell (structure) , layer (electronics) , anatomy , ramification , dorsum , biology , chemistry , paleontology , combinatorics , materials science , mathematics , composite material , genetics , organic chemistry
The wrinkle layer is a dorsal shell structure occurring in a number of ammonoids, but its function is still debated. Here, we describe, from Moroccan material of the Early Carboniferous species M axigoniatites saourensis (Pareyn, [Pareyn, C., 1961]), the most conspicuous wrinkle layer known within the A mmonoidea. This additional shell layer occurs in the ventrolateral portion of the adult body chamber and forms continuous lamellae, which range about two millimetres into the lumen of the body chamber. Possible functions are discussed and the most likely interpretation for the structure is ‘fabricational noise’, which is related to the coarsening of the shell ornament of the terminal body chamber.