X-ray phase technology shed new light on Weberian apparatus evolution: context and aim of the case study of †Chanoides (Otophysi, incertae sedis)

Abstract

Otophysan fish are identified as a natural group and have been studied as such since the first half of the 19th century. This very speciose group largely dominates the vertebrate diversity of inland waters today. In the 1980’s passionate debates concerned the otophysan radiation and notably their primary habitat: are they primitively freshwaters or marine animals? To answer we need to better understand the phylogenetic relationships including those of the fossils and thus we need to enhance our knowledge on key bony structures such as the Weberian Apparatus. In this context we propose a CT scan approach, for a specimen of †Chanoides macropoma. In the last years, palaeontology benefited from the developments of phase contrast X-ray microtomography. We expect great advances to investigate the Weberian apparatus and its evolution in Otophysan fishes.

Keywords

• weberian apparatus
• evolution
• stem otophysan
• fossil