The peppermint goby (Coryphopterus lipernes) can often be found lying on hard coral. They can be identified by their bright blue heads and yellow bodies. They're only about 3 cm long and very skittish, so getting a good picture takes patience. To get this picture, I swam in slowly, inching forward so that the goby became habituated to my presence. Once my camera was a in inch or so away from its head, I was able to take the photo.
Spinyhead blennies (Acanthemblemaria maria) live in small holes made by worms in the side of coral or other structures. The ones pictured have made their homes in fire coral (contrary to its name, fire coral isn't actually a coral, it's a hydroid). Spinyhead Blennies rest with their head outside the hole and the rest of the body inside so that their eyes can search for food and potential threats. Their eyes can actually look in different directions (in the third photo, one of the fish's eyes looks up and one looks to the side), an adaptation that allows them to focus on a potential predator and their prey at the same time.
As their name describes them, red-lipped blennies (Ophioblennius atlanticus) can be identified by their pinkish-red lips. They're more mobile than their smaller cousins, the secretary blennies; red-lipped blennies remain stationary with occasional hops from coral to coral. Although larger than secretary blennies, they are harder to photograph, as they often lie in the open where they are more skittish and less confident in their cover than secretary blennies which hide in holes.
The flamingo tongue (Cyphoma gibbosum) is a type of snail that is often found feeding on gorgonians (soft corals). Their colorful exterior is a membrane surrounding a hard shell within. The flamingo tongue's coloration may have developed as a way of warning predators not to eat it due to its poisonous properties. The snail ingests toxins from the soft corals it eats, and those toxins build up in its body, inflicting harm on predators that eat the flamingo tongue.
Christmas Tree Worm
Upon first glance, the Christmas tree worm (Spirobranchus giganteus) doesn't look like a worm at all. They look more like two feathers poking out of a coral or plants out of a sci-fi movie. However, the Christmas tree worm most certainly is a worm; the rest of its body is inside whatever surface the worm has dug itself into. The exposed, Christmas-tree-like parts (crowns) of the worm are used for respiration and to capture microscopic organisms floating in the water. If you get too close or make waves towards the worm, it will quickly close up and its crowns and recede into its hole.