This is one of my favorite fishes, the frogfish. They are related to the anglerfishes and have a lure to entice little fishes, like true anglers. Unlike the other anglers these guys are found in deeper waters hanging out on reefs, but not as deep as the true anglers who are also pelagic. Also, they are not ones for swimming. Their fins have an elbow-like joint which allows them to climb on the reefs. Apparently, they can jet-propel themselves by sucking in water and pushing it out the small gill opening behind the second set of fins . They can glide for a good distance before settling on the reef.
They are ambush predators, lurking on the reef looking like a lumpy rock or sponge. An unwary fish may settle next to them, or be attracted by the small waving lure... then snap. The frogfish can expand its mouth and guts to a considerable degree and swallow fish almost as large as itself [1,2].