Dendronephthya gigantea is a massive, arborescent soft coral (family Nephtheidae) widely distributed across the temperate and subtropical rocky reefs of the Indo-Pacific, with dense assemblages notably occurring around Japan and the Korean Peninsula. Morphologically, it forms large, tree-like arborescent colonies that can reach up to one meter in height, supported entirely by hydrostatic pressure and a dense internal matrix of heavily calcified, spindle-shaped skeletal elements called sclerites. As an asymbiotic (azooxanthellate) octocoral, this species lacks photosynthetic symbionts and relies exclusively on obligate suspension feeding, deploying thousands of translucent, eight-tentacled polyps to capture phytoplankton from strong, nutrient-rich tidal currents. Characterized by striking, vivid coloration ranging from bright orange to deep crimson—produced by pigmented sclerites—D. gigantea serves as a crucial structural ecosystem engineer, creating complex, three-dimensional benthic habitats that harbor diverse assemblages of associated marine micro-invertebrates and fish larvae.