Animals & Exhibits    >    Animal Guide    >    Invertebrates    >   

Midwater jelly

Midwater jelly

Not on Exhibit

Animal Facts

  • Scientific Name

    Colobonema sericeum

  • Animal Type


  • Diet

    small crustaceans

  • Size

    1 inch (2.5 cm) in diameter

  • Relatives

    other hydromedusae; Family: Rhopalonematidae

  • Habitat

    Deep Sea

  • Range

    midwater (2,297-3,281 feet, or 700-1,000 m)

Natural History

Colobonema is found in many regions of the world. Compared to a lot of jellies, it's a strong swimmer. It's equipped with 32 tentacles. When disturbed, its tentacles can drop off, confusing a would-be predator. Scientists suspect that Colobonema can re-grow the dropped tentacles, since they often observe this jelly with tentacles of different lengths.


Anything that finds its way into the ocean—whether it's tossed away as trash or washed off a beach or boat—may eventually make its way to the deep sea. It's important to realize that the deep sea is not so far away that it's beyond the reach of human activities. Living creatures in the deep are affected by what we do at the surface.

Cool Facts

Colobonema is a carnivorous ambush predator that drifts motionless with its tentacles outspread, waiting for unsuspecting prey.

 Animal Guide Home