To describe the developmental stages of internally brooded larvae of the scleractinian cold-water coral Caryophyllia (Caryophyllia) huinayensis total of 20 parent polyps were collected in 2014, 2015, and 2019. Scientific SCUBA divers chiselled the polyps from the substrate at three sites – X-Huinay (42.386883°S, 72.462867°W), X-Telele (42.279183°S, 72.462867°W), and Liliguapi (42.162833°S, 72.596467°W) – at depths of 20–30 m in Comau Fjord, southern Chile. The collected polyps were fixed, decalcified, embedded in paraffin wax, sectioned (3 µm thickness, 45 µm spacing), and stained with haematoxylin-eosin. For further digital processing, such as tissue measurements and three-dimensional reconstructions, the histological slides were scanned using a Philips IntelliSite Ultra Fast Scanner at 40× magnification (0.25 μm per pixel). This resulted in approximately 208 GB of high-resolution image data saved as tiff, providing unique insights into the development and release of larvae within the parent polyps.