Benwood wreck, Key Largo, 40 feet

French Reef, Key Largo, 45 feet

Fluorescent, Benwood wreck, Key Largo, 40 feet

Common on shallow reefs.  Massive hemispheres or encrusting, with large domed calices, tan, greenish, grayish, or dark brown, extended tentacles may be contrasting color.  Bermuda, Florida to Brazil, & Tropical West Africa.