Miniscule rare shark with a secret pocket that is still a mystery to scientists
The Pocket shark (Mollisquama parini) is a Kitefin shark of the family Dalatiidae. Two Pocket sharks have been found in deep water off Chile in the southeast Pacific Ocean and recently in 2010 in the Gulf of Mexico. It is distinguished from other sharks by its pocket next to its front fins. The pocket is large, measuring about 4% of the shark’s body length. Some researchers hypothesize that they may secrete some kind of glowing fluid in counter illumination or pheromones, or both.
Family: Dalatiidae – Kitefin sharks
Common Name– Dogfish Sharks
Common Name– Kitefin Sharks
Status: IUCN Red List DATA DEFICIENT
Average Size and Length: The first Pocket shark specimen was an adolescent female 1.3 feet total length. The second specimen was a recently born male at 5.5 inches long.
Average Weight: The male shark found in the Gulf of Mexico weighed 14.6 grams.
Current Rare Mythical Sightings: “The Pocket shark we found was only 5 and a half inches long, and was a recently born male,” said Mark Grace of NOAA Fisheries’ Pascagoula, Miss. Read about the second Pocket shark specimen shark found here
Teeth and Jaw: From the one finding of the pocket shark in the Gulf of Mexico, the mouth was described to have a rectangular like opening on the underside of the body. It has thick fringed lips.
Head: The Pocket shark has a wide, short, blunt rounded or conical snout tapers back toward caudal fin.
Tail: The caudal fin is asymmetrical and not paddle-like with a weak lower lobe.
Demographic, Distribution, Habitat, Environment and Range: The first Pocket shark was found off the coast of Chile in the Nazca Submarine Ridge, taken at a depth of 1,083 feet, in 1979. In February 2010, a 5.5-inch-long specimen was caught 190 miles off the coast of Louisiana, in the Gulf of Mexico. It is now believed that they are more widely dispersed than what was previously hypothesized.
Aesthetic Identification: The overall shape of the Pocket shark is cylindrical, it is dark grey-brown in color. The fins are dark with light margins. It has medium-sized gill-slits, the fifth almost twice the length of the first. The first dorsal fin is well behind the pectoral fins. The base is just in front of the pelvic bases. The second dorsal fin is about as large as the first.
Biology and Reproduction: The Pocket shark gets its name from a respectively large pocket gland with a slit-like opening that is found behind the two pectoral fins on either side of the shark. The purpose of this gland is still unknown as not enough species have been found to investigate the matter. The closest suggestion for the purpose of this gland is to act as a luminous pouch as found on the Taillight shark. This pocket gland appears to have a slighter dark brownish-gray coloration thank the body. The pocket is located approximately 2.5 mm from the base of the pectoral fin and was measured to be 13.0 mm long and 5.0 mm wide. Some researchers hypothesize that they may secrete some kind of glowing fluid in counter-illumination or pheromones, or both.
Behavioral Traits, Sensing and Intelligence: Unknow.
Pocket Shark Recorded Attacks on Humans: Not a threat to humans.