Overview
The Velvet Belly Lanternshark (Etmopterus spinax) is a captivating, bioluminescent deep-sea dogfish shark native to the deep waters of the eastern Atlantic Ocean and Mediterranean Sea. Inhabiting bathyal continental slopes, deep fjord basins, and muddy abyssal plains down to 6,500 feet (2,000 m), this small, elegant shark produces its own living light to perform counterillumination camouflage, disguising its silhouette against downwelling ocean light while signaling to conspecifics in the deep twilight zone.
Biology and Physical Characteristics
Characterized by a slender, cylindrical body, Etmopterus spinax features two dorsal fins preceded by stout, grooved spines. Its coloration is marked by a sharp, dramatic contrast: the upper body is a warm brown or slate-gray, transitioning abruptly into an intensely dark, velvety-black underside on the belly, pelvic area, and tail. Embedded within this dark ventral epidermis are thousands of microscopic light-emitting photophores controlled by melatonin and prolactin hormones, which emit a continuous, soft greenish-blue glow matching ambient downwelling sunlight.
Behavior and Ecology
Operating as a versatile mesopelagic and bathypelagic predator, the Velvet Belly Lanternshark undertakes diel vertical migrations, following dense schools of lanternfishes (Myctophidae), deep-water squids, and pasiphaeid shrimps upward into intermediate water layers at dusk. Aside from ventral counterillumination that renders it invisible to predators hunting from below, the shark also features luminous lateral flank markings that function as glowing ‘sabers’ or species-recognition badges in the dark abyss. It is ovoviviparous, with females giving birth to litters of 6 to 20 live, fully formed pups.
Conservation and Human Impact
The IUCN assesses Etmopterus spinax as Least Concern across its broad geographical distribution, where it remains one of the most abundant deep-water elasmobranchs in the northeastern Atlantic. Although not targeted commercially for human food due to its small stature, it is frequently taken as discards in commercial deep-water bottom-trawl and longline fisheries targeting deep-sea shrimp, hake, and Norway lobster. Marine ecological sanctuaries and restrictions on deep-sea bottom trawling within Mediterranean submarine canyons provide vital refuges.
Interesting Factoid
The Velvet Belly Lanternshark features photophores lining its defensive dorsal fin spines, which literally illuminate the spines like glowing lightsabers in the pitch-black abyss, warning larger predatory fish that an attack will result in a painful mouth puncture.
Last updated: October 2026