Lophelia pertusa colony sample POS455-C1W originates from Sula reef, off Norway, where it was taken with the submersible Jago during Poseidon cruise POS455 (white colourmorp). The coral colony fragment was scanned by a Toshiba Aquilion 64 computer tomograph (CT) at the hospital Klinikum Bremen-Mitte with an x-ray source voltage of 120 kV and a current of 600 mA. The CT image stack has a resolution of 0.35 mm in x-direction and y-direction and 0.5 mm resolution in z-direction (0.3 mm reconstruction unit, https://doi.org/10.1594/PANGAEA.947276). This dataset contains the calices segmentation (given as unique label values) for the initial polyp-cavity segmentation (published here: https://doi.org/10.1594/PANGAEA.947276) and a spreadsheet containing the (directed) edges of the colony skeleton graph. Each label in POS455-C1W-calcies dataset represents a vertex in this graph. The edges are given by their start label Node ID #1 and the label of their target Node ID #2.