Family: Squatinidae – Angel Sharks
Common Name– Angel Sharks or Angelsharks
Status: IUCN Red List NOT EVALUATED
Average Size and Length: The maximum length recorded so far has been 49 cm/1.6 feet.
Current Rare Mythical Sightings: The Latin name heteropteran refers to the obvious difference in size, shape and area of the two dorsal fins.
Teeth and Jaw: The mouth is very wide and placed terminally. They have expendable necks and trap-like jaws that can rapidly snap upwards and hinge shut. They have long, needle-like teeth in the upper and in the lower jaws used for gripping. Each side of the jaws have 8 triangular, non-serrated straight teeth. The upper jaws have 2 functional series, the lower jaws only have 1.
Head: The nasal lobes are simple and similar in length. The first and last are spatula-like in shape. The central part is irregularly quadrangular its edge has several lobes.
Denticles: The Disparate angelshark has no thorns or enlarged denticles on the mean dorsal line. The dermal denticles have 4 keels extending posteriorly, which is its widest base, and approximately twice its length.
Demographic, Distribution, Habitat, Environment and Range: The Disparate angelshark can be found in the western Atlantic in the Gulf of Mexico. They are considered marine demersal to a depth range of down to 538 feet (known) in tropical climates.
Ram-Suction Index: They have an RSI more towards the suction end of the scale. They lay flat and still on the bottom, when the time comes, they lung at prey and suck it into their mouths with negative pressure.
Aesthetic Identification: The Disparate angelshark is dark brown dorsally, without any ocelli. There are 2 distinct round black spots on the upper edge of the pectoral fins, there are also irregular scattered whitish spots. The dorsal fins are very different in size, shape and area, with their base about half their height.
Biology and Reproduction: The biology and reproduction are unknown; however, they are presumably ovoviviparous.
Behavioral Traits, Sensing and Intelligence: The Disparate angelshark is lethargic by day and lies buried still in the mud or in the sand mud with only their eyes distended out, waiting to ambush prey.
Disparate angelsharks have a unique way of breathing compared to most other benthic sharks and fish. They do not pump out water from the oropharyngeal cavity. 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 unnoticeable and prevent detection from unwanted predators.
Disparate Angelshark Recorded Attacks on Humans: The Disparate angelshark is not dangerous to humans unless provoked. Because of their powerful jaws and sharp teeth, they can inflict injury on anyone or anything that may pose a threat to them. There have been cases of Angel sharks biting divers that have tried to restrain them, approach too close to the head, corner them, or grab their tails.
(Castro-Aguirre, J.L., H.S. Espinosa Pérez and L. Huidobro Campos, 2006. “Dos nuevas especies del género Squatina (Chondrichthyes: Squatinidae) del Golfo de México”. Rev. Biol. Trop. (Int. J. Trop. Biol.)  54 (3):1031-1040).