The Squatiniformes, or common name Angel Sharks are an order of sharks that is comprised of one family, Squatinidae (also common name Angel sharks or Angelsharks), which are unusual in having flattened bodies and broad, triangular pectoral fins that give them a strong resemblance to rays. The rear has a muscular appearance. The eyes and spiracles are on top and the five gill slits are on its back. Both the pectorals and the pelvic fins are large and are horizontally origin. There are two dorsal fins, no anal fin and the lower lobe of the caudal fin is longer than the upper lobe. They can grow on an average of 5 feet in length.
Angel sharks have very large mouths, and nostrils with barbels on the anterior nasal flaps. They have expendable necks, and trap-like jaws can rapidly snap upwards and hinge shut to capture prey. They have long, needle-like teeth perfect for gripping. Angel sharks are ambush predators, and bury themselves in sand or mud lying while they wait for prey. They eat fish, crustaceans and various types of mollusks. They have an RSI more towards the suction end of the scale. They lie on the bottom completely camouflaged and motionless, lung, and suck prey into their mouths. Since they must blend into their bottom environments, many have unique patterns above, and mostly pale below.
Angel sharks can be found worldwide in cool, temperate and tropical seas over continental shelves (intertidal to continental slopes). If in tropical waters, they are found to inhabit deeper water, some down as deep as 4,300 feet. They are mostly absent in the Indian Ocean and the central Pacific Ocean. Research suggests that they do not swim long distances or venture far at all.
Angel sharks have a unique way of breathing compared to most other benthic fish. They do not pump out water from the oropharyngeal cavity like other fish. Instead they use gill flaps located on the sides of their body to pump out water during respiration. Doing so also allows them to be more discreet and prevent detection.
Angel sharks are ovoviviparous, and have between 1-25 pups per litter. Not much is known about their reproduction, but research suggests there may be differences by location.
Some species are very difficult to tell apart from one another. In the past, Angel sharks were known as Monkfish.