Angler Fish

You’ve probably seen images and even video of the deep-sea anglerfish, but here’s an up-close look, in its natural habitat 2,000-feet underwater. This video was captured by MBARI’s ROV Doc Ricketts at 600m (1968.5 ft) on a midwater research expedition in November 2014. Sea devils are the family of deep-sea anglerfish known as the Ceratiidae, from the Greek keras, “horn”, referring to the bioluminescent lure that projects from the fishes’ forehead. Continue reading to watch.

They are large and elongated: females of the largest species, Kroyer’s deep sea angler fish, Ceratias holboelli, reach 1.2 m (3.9 ft) in length. Males, by contrast, are much smaller, reaching 14 cm (5.5 in), and, like other anglerfishes, spend much of their lives attached to a female after a free-living adolescent stage in which they are very small – at most 1.3 cm (0.51 in) – and have sharp, beak-like, toothless jaws. One or more males attach themselves permanently to a female, eventually merging circulatory systems. As this genetic chimera matures, the male grows large testicles, while the rest of its body atrophies. Ceratioidea are the only creatures known to become chimeras as a normal part of their lifecycle.

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