Author: Linda Weiss
Spined Pygmy Shark
(Squaliolus laticaudus)
Key Features/Appearance
The Spined Pygmy Shark is a very small fish. The longest recorded is only 28 cm (11 inches) long for females and 22 cm (8.7 inches) long for males. Their body shape is elongated with a long bulbous snout that’s pointed at the end. Coloration is dark brown to black with some light, cream coloration on its fins. Its large eyes are located approximately half way between its mouth and the end of its snout. Pectoral fins are triangular in shape and short. Pelvic fins are long and there is not an anal fin. The caudal fin has similarly sized broad, rounded lobes. The first dorsal fin is small and contains a spine, while the second dorsal fin has a longer base and no spine. The underside of this shark is covered in photophores for bioluminescence. The upper jaw of the Spined Pygmy shark contains 22-31 rows of teeth with 16-21 rows in the lower jaw. Teeth in the upper jaw are smooth and narrow with only one cusp. Teeth in the lower jaw are also single cusped with broad, interlocking bases.
Image credit: Luciano Fischer ( via Smithsonian Tropical Research Institute)
Habitat and Distribution
This is deep water species of shark found at depths between 200-500 m (660–1,640 feet). It has a patchy distribution in the Atlantic, and Indo-Pacific Oceans. Areas in the Atlantic include the Gulf of Mexico off of the United States, Bermuda, southern Brazil, northern Argentina, and northern France and Madeira. Areas of distribution in the Indo-Pacific include Somalia, Taiwan, Philippines and southern Japan.
Credit: SEFSC Pascagoula Laboratory; Collection of Brandi Noble, NOAA/NMFS/SEFSC
Diet
The Spined Pygmy shark eats squid and small bony fishes.
Reproduction
This shark species reproduction method is ovoviviparous. Eggs are fertilized inside the female, receiving nourishment from yolk sacs for development until being live-birthed, fully developed. An average litter size is 4 pups, each measuring 9-10 cm (3.5-3.9 inches) in length.
Status
The IUCN Red List of Threatened Species currently lists the Spined Pygmy shark as Least Concern, with a stable population trend.
Threats
Due to its small size the Spined Pygmy shark is not targeted by either the commercial or sport fishing industries. It is sometimes caught as by-catch during commercial fishing practices. If it has specific natural predators, those are not known at this time.
References
Planet Shark Divers
Shark Ray Research
Sharkwater
The IUCN Red List of Threatened Species
Finucci, B., Cheok, J., Cotton, C.F., Kulka, D.W., Neat, F.C., Rigby, C.L., Tanaka, S. & Walker, T.I. 2020. Squaliolus laticaudus. The IUCN Red List of Threatened Species 2020: e.T60214A3093390. https://dx.doi.org/10.2305/IUCN.UK.2020-3.RLTS.T60214A3093390.en. Accessed on 11 June 2022.
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