Microstructure and affinity of the enigmatic Devonian tubular fossil Trypanopora
Version of Record online: 9 OCT 2007
Volume 24, Issue 2, pages 227–234, April 1991
How to Cite
WEEDON, M. J. (1991), Microstructure and affinity of the enigmatic Devonian tubular fossil Trypanopora. Lethaia, 24: 227–234. doi: 10.1111/j.1502-3931.1991.tb01471.x
- Issue online: 9 OCT 2007
- Version of Record online: 9 OCT 2007
- received 16th July, 1990, accepted 3rd January, 1991.
The adult shell (teleoconch) of the enigmatic tubular Givetian fossil Trypanopora is comprised of two principal layers: an outer fibrous prismatic layer and an inner micro-lamellar (irregular cross-bladed) layer, with local, closely-spaced disruptive punctation. The fine preservation suggests an original calcite composition. The shell microstructure shows great similarities with that of both vermiform ‘gastropods’ and tentaculitoids, suggesting a close affinity between Trypanopora and these groups. The septa have an irregular micro-lamellar (cross-bladed) microstructure in continuity with the inner wall, and a morphology unlike that of any known mollusc. The class Tentaculitoidea is emended to include two new orders: Microconchida for the vermiform ‘gastropods’ and Trypanoporida for Trypanopora and allied genera. □Trypanopora, microstructure, protoconch, teleoconch, fibrous prismatic layer, micro-lamellar layer, tubulation, septation, vermiform ‘gastropods’, Tentaculitoidea, Microconchida, Trypanoporida.