A Predatory tunicate looks like a jellyfish that has taken the form of a Venus flytrap in the deep.
But there is a lot more to it.

Predatory Tunicate   © Monterey Bay Aquarium

Predatory tunicates (Megalodicopia hians) are carnivorous invertebrates that live anchored along canyon walls 200 to 1000 meters in the deep sea. Its open hood is constantly waiting for tiny animals like zooplankton to swim by, so it can rapidly close it to trap the prey inside.

Predatory tunicates are simultaneous hermaphrodites — each animal produces both eggs and sperm. If conditions are poor and the nearest mate is out of reach they will fertilise their own eggs to ensure successful reproduction.

This animal is a distant family member, as both humans and tunicates belong the phylum Chordata. The hood-and-stalk physiology of the tunicate may appear squishy, but they reveal more similarities in the larval stage, just after hatching when they take on a body structure similar to tadpoles.

During this brief stage of life, the developing organisms exhibit a sort of primitive, flexible backbone called a notochord. Also, a nerve cord runs down their relatively long, muscular tails, which help propel them through their aquatic environment once they are released from their eggs.
An important tool of orientation for the small organism is the ability to detect gravity and sense light, which purpose at this point in the life cycle is to find a suitable location for metamorphosis.

The form-changing process affects many physical changes to the tunicate’s body.
One of the most interesting is the digestion of the cerebral ganglion, which controls movement and is the equivalent of the human brain. From this comes the common saying that the sea squirt “eats its own brain”. The notochord is lost and transforms the animal into an invertebrate that is permanently attached to the sea floor.

In growing to adulthood, tunicates develop a thick protective covering around their barrel-shaped bodies which gives the animal its name.

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