Gracilitheca and Nephrotheca (Hyolitha, Orthothecida) in the Cambrian of the Barrandian area, Czech Republic

Abstract

VALENT, M., FATKA, O. & MAREK, L., iFirst article. Gracilitheca and Nephrotheca (Hyolitha, Orthothecida) in the Cambrian of the Barrandian area, Czech Republic. Alcheringa, 1–10. ISSN 0311-5518.

Five orthothecid hyoliths, Gracilitheca mirabilis sp. nov., Gracilitheca triangularis sp. nov., Gracilitheca sp., Nephrotheca betula sp. nov. and Nephrotheca sp. are described from the ‘middle’ Cambrian Buchava Formation of the Skryje–Týřovice Basin in the Czech Republic. The new forms are based on about forty well-preserved external and internal moulds of conchs; opercula of all species remain unknown. Stratigraphic ranges and geographic distributions within the Skryje Týřovice Basin are established for all taxa.

本文描述了捷克共和国Skryje-Tyřorice盆地“中”寒武统Buchava组中的五个直管螺类软舌螺的种:Gracilitheca mirabilis sp. nov.、Gracilitheca triangularis sp. nov.、Gracilitheca sp.、Nephrotheca betula sp. nov. 及Nephrotheca sp.。新类型的建立是依据约四十个保存良好的螺体外、内模;其鳃盖情况未知。我们已确定所有类群在该盆地中的地层和地理分布。

Key words:

• Hyoliths
• Orthothecids
• ‘middle’ Cambrian
• Skryje–Týřovice Basin
• Barrandian area
• Czech Republic

Acknowledgements

We would like to express our thanks to John Malinky (Escondido) and Timothy P. Topper (Copenhagen) for helpful comments and suggestions, which greatly improved the clarity of the paper. This study was supported by MSM 0021620855 (Material flow mechanisms in the upper spheres of the Earth), the Czech Science Foundation through the Project N° 205 / 09 / 1521 (Feeding strategies in Cambrian to Middle Ordovician of the Barrandian Region) and by a project of the Ministry of Culture CR No. DF12P01OVV021. This paper is a contribution to International Geoscience Programme (IGCP) 591, ‘The Early to Middle Palaeozoic Revolution’.