Peculiar tube-like bivalve with densely packed concave tabulae (?tramberk Limestone, Tithonian-Berriasian)

The fossils described here are from the Tithonian-lower Berriasian Stramberk Limestone of the Czech Republic. The specimens consist of densely packed, straight to slightly curved short tubes. Each tube is composed of a single valve rather than two valves. Some tubes show constrictions in the wall, generally on just one side. The lumen is almost completely filled with numerous densely packed slightly to strongly concave tabulae. In some tubes, the tabulae form complete internal floors while in others they connect to the wall with another tabula or seal the concavity in the underlying tabula. The tubes somewhat resemble tubeworms, rudists, vermetids and calcareous algae. However, based on morphological similarities such as the tube-like morphology in longitudinal section and the shapes of the lamellae and tabulae, these tubes resemble oysters described from the Albian of Brazil. According-ly, we infer that the Stramberk tubes represent oysters or oyster-related bivalves.

Automated summary

The described fossils are short tubes from the Stramberk Limestone in the Czech Republic, composed of single valves. The tubes resemble oysters due to their tube-like morphology and the shapes of their lamellae and tabulae. Therefore, the Stramberk tubes are inferred to represent oysters or oyster-related bivalves.