(photo by Adam Laverty)

The caribbean reef octopus (Octopus briareus) is characterized by its distinctive blue-green color with occasional mottled-brown markings. Like other octopus species, the Caribbean reef octopus is solitary animal and able to quickly change color using specialized cells in their skin known as chromatophores. The Caribbean reef octopus is common throughout the Western Atlantic, Bahamas, Caribbean and the coasts of northern South America. It is often found at night feeding on reefs and sea grass beds. Because their blue-green skin is so reflective, they are easy to spot at night with dive lights.

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alongthereef:www.daveharasti.com lionfish (see this previous post for more information)

(source of photo here)

The mantis shrimp (Pseudosquilla cilata) is a marine crustacean. These shrimp are neither shrimp nor mantids, but receive their name purely from the physical resemblance to both the terrestrial praying mantis and the shrimp. They typically reach 12” in length. Mantis shrimp appear in a variety of colors, from shades of browns to bright neon colors. Mantis shrimp are long-lived and exhibit complex behavior, such as ritualised fighting. Some species use fluorescent patterns on their bodies for signalling with their own and maybe even other species, expanding their range of behavioral signals. They can learn and remember well, and are able to recognize individual neighbors with whom they frequently interact. These aggressive and typically solitary sea creatures spend most of their time hiding in rock formations or burrowing intricate passageways in the sea-bed. They either wait for prey to chance upon them or, unlike most crustaceans, actually hunt, chase and kill living prey

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