Very small, spindle shaped body. Pointed, long and bulbously shaped snout. The only known shark with a spine on its first dorsal fin but not on the second one. First dorsal fin with its origin opposite to the inner margins or rear tips of pectoral fins. No anal fin.
Coloration
Dark (black) with conspicuously light-margined fins.
Distribution
Oceanic and nearly circumtropical. Western Atlantic: Bermuda, southern Brazil, northern Argentina. Eastern Atlantic: France and Madeira. Indian Ocean: Somalia. Western Pacific: Japan, Taiwan, Philippines.
Biology
This species lives over the continental slopes, between 200 m and 500 m depth. It is known to vertically migrate. Spined pygmy sharks have photophores that produces bioluminescent light on the undersides of their bodies. ( A few are also located on their backs. These photophores are also used for "counter shading", making them less visible against the ligher background (i.e.the surface and surface light) from below and therefore more protected from predators.
Diet
Cephalopods, lanternfishes and other fishes of deeper water.
Size
Probably the smallest shark of all, maximum size about 25 cm.
Reproduction
Aplacental viviparous (ovoviviparous). Males reach sexual maturity at about 15 cm, females at about 17 cm to 20 cm.
Similar Species
None.
Vulnerability
Category:Least Concern (LC) Criteria: - Last evaluated:2020 Trend: