Comb jellies’ eight rows of comblike cilia act as paddles. In the 1980s a rapidly multiplying species decimated Black Sea fisheries. Beroe abyssicola, 4.7 inches long Aequorea victoria.

The comb jelly, which devastated the fishing industry in the anchovy-rich Black Sea in the 1980s, was recently discovered in the Bornholm Basin, seat of the Baltic Sea’s cod population.

However, the sea walnut, a comb jelly native to the eastern Atlantic ... explain its success as an invasive species, first in the Black Sea and now across parts of Europe and Asia.

How reverse development allows comb jellies to survive harsh conditions ... "There is a theory that the collapse of fisheries in the Black Sea [in the 1990s] was caused by Mnemiopsis," said ...