Phenotypic regionalization of the vertebral column in the thorny skateAmblyraja radiata: Stability and variation

• DOI: 10.1111/joa.13551
• Publication Date: 2021-09-20T04:29:04Z
• Authors: Fidji Berio; Yann Bayle; Cyrena Riley; Olivier Larouche; Richard Cloutier
• Keywords: Vertebral column; Radiata

Abstract Regionalization of the vertebral column occurred early during vertebrate evolution and has been extensively investigated in mammals. However, less data are available on regions crown gnathostomes. This is particularly true for batoids (skates, sawfishes, guitarfishes, rays) whose long considered to be composed same two as teleost fishes despite presence a synarcual. numerous units chondrichthyans may display more complex regionalization pattern than previously assumed intraspecific variation such deserves thorough investigation. In this study, we use micro‐computed tomography (µCT) scans columns growth series thorny skates Amblyraja radiata provide first fine‐scale morphological description species. We further investigate axial using replicable clustering analysis presence/absence elements decipher A. . identify four The anteriormost regions, named synarcual thoracic, undergo strong developmental or functional constraints because they stable patterns shapes numbers across all stages. third region, hemal transitional, characterized by high inter‐individual displays transition between monospondylous (one centrum per somite) diplospondylous (two centra conditions. posteriormost caudal, subdivided into three sub‐regions with changing gradually along anteroposterior axis. These regionalized discussed light ecological habits skates.