μCT Scanning Datasets of Coprolites Containing Bones of Keichousaurus hui (Reptilia: Sauropterygia) from the Middle Triassic Xingyi Fauna, Yunnan Province, China

Raw projection data were imported into VG Studio Max 3.0 for processing. Bone and matrix were separated by thresholding, and each bone was manually outlined slice by slice to create regions of interest and generate 3D models. Anatomical identification was conducted through comparisons with Keichousaurus hui specimens from the same horizon, and identical skeletal elements were colored uniformly.The dataset comprises five compressed packages totaling approximately 83.4 GB.

CD-1.zip (22 GB), CD-2.zip (21 GB), CD-3.zip (20 GB), and CD-4.zip (20 GB) contain the CT data of the four pieces, each including raw projection images (.tiff), a 3D reconstruction video (.avi), and a scanning parameter file (.txt). CD.zip (26 KB) stores a PDF file of the reconstructed Keichousaurus hui bones. Temporal coverage is the Middle Triassic, and spatial coverage is Luoping County, with spatial resolutions as listed above.

Table 1 presents the counted bone fragments, with four data rows for the specimens and one summary row; column headers are anatomical abbreviations (e.g., dr for dorsal rib, ul for ulna), and the unit is “number of elements”. Because bone and matrix exhibit only slight density contrast, grayscale differentiation in some regions is limited, leading to lower visual separation in the 3D rendering videos. However, manual segmentation and repeated verification allowed the reliable extraction of at least 69 bones of subadult Keichousaurus hui.

All identified elements are from the postcranial skeleton; no skull remains or fish scales were recognized, indicating good internal data completeness. Minor boundary uncertainties may exist because of manual delineation and scanning resolution; users are advised to cross‑reference with raw projection data when high precision is required.