Stylopoma thornelyi is found from Vanuatu, Tahiti, the South China Sea and the GBR region.
Original description: Stylopoma viridis var. thornelyi Livingstone, 1926.
Locality: Ellison Island, Great Barrier Reef, Queensland, Australia.
Holotype: AM U2324.
Description from Tilbrook, 2001 (PDF file)
Description from Tilbrook, 2006.