Velvet fishes

Scientific name : Aploactinidae

Small and poorly known family, belonging to the order Scorpaeniformes (often confused with the scorpionfishes). Very seldom observed due to the cryptic behaviour.
Like all Scorpaeniformes they have a bony ridge along the cheeck, and spiny head. Body is squat, elongate, almost cylindric. Compared with the typical fish anatomy, they miss the gas bladder: their buoyancy is negative, therefore they simply lay on the bottom.
Usually observed on sandy bottoms, partially hidden among detritus, in bay. Their movements are very limited, they do not swim but rather crawl heavily, using pectoral and ventral fins.
At a first glance, confusion is possible with scorpion fishes and wasp fishes families. Compared with the former they have body more elongated and the first dorsal fin with fewer spiny rays. Compared with the latter have less compressed, squat, shape.