Abyssal Comb Jelly

Beroe abyssicola

Beroe abyssicola is a pelagic ctenophore that inhabits the deep waters of the North Pacific Ocean, particularly around Japan and the Arctic Ocean. It can be found at depths exceeding 400 meters, with recorded occurrences up to 2000 meters. This species is characterized by its muscular, flat, and cylindrical body, which can grow up to 7 cm long. Unlike many other ctenophores, B. abyssicola lacks tentacles at all life stages, making it distinct. Its body is more opaque than other ctenophores and can exhibit red or purple coloration. When not feeding, its large mouth remains closed, held together by adhesive bands of epithelial cells. As a predator, B. abyssicola primarily feeds on smaller ctenophores, particularly Bolinopsis infundibulum. It employs large cilia inside its mouth, known as macrocilia, which function like teeth to retain and tear its gelatinous prey. The ctenophore uses its flexible body and comb rows to swim mouth-first, constantly searching for food. B. abyssicola has a unique nerve net that directs its swimming and feeding behaviors, with a concentration of nervous function located in the aboral organ. Beroe abyssicola is hermaphroditic, with eggs developing into planktonic juveniles before maturing into adults. Encounters with this species during dives can be intriguing, as divers may observe its swimming patterns and feeding behaviors. The conservation status of B. abyssicola is currently not evaluated, indicating a lack of specific data on its population trends.