Morphology and microstructure of oligoiamellar teeth in Paleozoic echinoids Part 2. Givetian (Middle Devonian) stage of evolution of oligolamellar teeth
Wanda Jesionek-Szymańska
Oligolamellar echinoid teeth, primitive in general morphology, are represented in the Givetian of the Skały beds (Grzegorzowice-Skały Section, Holy Cross Mts., Poland) by a few types differing mainly in fine details of their adaxial surfaces which may be smooth , ledged or denticulate. It is suggested that these characters reflect the adaptation to particular feeding habits. A new kind of Givetian echinoid teeth, closely related to the oligolamellar one is described. In som e characters such as greater number of lamellae which also are thinner, they seem to be "intermediate" between oligoiamellar and another group of Givetian echinoid teeth, for which the name multilamellar is proposed. It is newly re cognized and briefly characterized.
Key words: echinoids, evolution, jaw apparatus, microstructure, Devonian.
This is an open-access article distributed under the terms of the Creative Commons Attribution License (for details please see creativecommons.org), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Full text (2,080.7 kB)