The holocephalan ratfish endoskeleton shares trabecular and areolar mineralization patterns, but not tesserae, with elasmobranchs little skate and catshark

Abstract Specific character traits of mineralized endoskeletal tissues need to be clearly defined and comprehensively examined among extant chondrichthyans (elasmobranchs, such as sharks and skates, and holocephalans, such as chimaeras) to understand their evolution. For example, tiles of mineralized polygonal structures called tesserae occur at cartilage surfaces in chondrichthyans, but recent studies showing trabecular mineralization at elasmobranch cartilage surfaces suggest that tesserae are not as common as previously thought. Also, while areolar mineralized tissue in elasmobranchs is generally considered a unique, shared chondrichthyan feature, some chondrichthyan species demonstrate bone-like tissues in both a specific region of tesserae termed the cap zone and continuous (not tiled) mineralized neural arches. To clarify the distribution of specific endoskeletal features among extant chondrichthyans, adult skeletal tissues in a holocephalan chimaera (spotted ratfish) and two elas..., , # Data from: The holocephalan ratfish endoskeleton shares trabecular and areolar mineralization patterns, but not tesserae, with elasmobranchs little skate and catshark Dataset DOI: [10.5061/dryad.0cfxpnwfq](https://doi.org/10.5061/dryad.0cfxpnwfq) ## Description of the data and file structure Data contained in the files listed below are desktop and Synchrotron radiation micro-CT projections of shark (S. canicula), skate (L. erinacea), and chimaera (H. colliei): **Desktop projections:** * Atake_et_al_chondrichMinTissuesRawData_Figs.1B-G__2C_F__3D_H__5C__6D.zip * Atake_et_al_chondrichMinTissuesRawData_Figs.2A_D__3B_F__5A.zip * Atake_et_al_chondrichMinTissuesRawData_Figs.2B_E__3C_G__5B.zip * Atake_et_al_chondrichMinTissuesRawData_Fig.3A_E.zip * Atake_et_al_chondrichMinTissuesRawData_Fig._6B.zip * Atake_et_al_chondrichMinTissuesRawData_Fig._6C.zip **Synchrotron projections:** * Atake_et_al_chondrichMinTissuesRawData_Fig._4B-E.zip * Atake_et_al_chondrichMinTissuesRawData_Fig._4G-J.zi...,