Predatory Tunicate

## About

A predatory tunicate.

The predatory tunicate ***(Megalodicopia hians)*** also known as the deep sea tunicate, is a species of tunicate that is unique among its kind for employing filter-feeding tactics when hunting. The predatory tunicate is an extremely seldom-documented animal and as a result little information is available as of writing this article. The species has no discernable facial features and has a glossy translucent body, which includes a large orifice and a stem-like 'body'. The lips of the predatory tunicate -which are formed through hypertrophy- form a 'hood' that resembles a mouth and functions like a stomach. Though the hood of the tunicate may appear stiff and immovable, it is quite the opposite, actually being able to quickly close around its prey. Predatory tunicates are anchored to the sea-floor, which leads them to often be mistaken as plants. The predatory tunicate measures only to 13cm (5in) in length.

## Diet

Predatory tunicates are well recognised among their relatives for their ability to filter feed. Filter feeding is extremely beneficial for the species, as it is immobile and relies on the ability to catch in its prey via its hood. The predatory tunicate consumes an array of micro-organisms such as zooplankton. As they are anchored to the sea-floor, predatory tunicates rely on the current to sweep unsuspecting prey into their hoods. Once captures, the hood will then close around the prey, locking it inside until digested.

## Conservation Status

The predatory tunicate is yet to be evaluated by the IUCN and so does not have an official conservation status. Monterey Bay Aquarium says that the predatory tunicate is most threatened by pollutants like plastic waste, which makes its way to the deeper ocean from the surface.

## Range and Population

Currently the predatory tunicate is only known from Monterey Canyon, California. Here, the tunicate inhabits depths of 183-1,000m (600-3,300ft) and lives perpetually anchored to the walls of the canyon. They are said to be most prolific in numbers in the oxygen-minimum zone, about 400-800m (1,300-2,600ft). The population and population trend of the species has not be justified.

## Behaviour

The predatory tunicate is known to by hermaphroditic, meaning that an individual of this species possesses both the male and female reproductive organs. This is useful, as it allows tunicates to reproduce in low population-dense areas by themselves. If mating does occur between two individuals, they will drift the semen and eggs into the open water, allowing them to be fertilised. Due to seldom-documentation, little else is known about the species' behavioural and breeding characteristics.

### Relationship with Humans

This species rarely, if at all, interacts with humans.

## In Captivity

As of currently, the Monterey Bay Aquarium, USA, is the only aquarium to house predatory tunicates. The facility houses them in their 'Into the Deep' exhibition. According to the New York Times, the Monterey Bay Aquarium acquired these rare animals by venturing into the deep using submersibles and retrieving the tunicates with heavy machinery, sensory equipment and extreme caution. With the exhibition of the predatory tunicate, the Monterey Bay Aquarium confidently declared that they can safely retrieve deep sea wildlife for public viewing.

## Sources

* Predatory Tunicate | Wikipedia - https://en.wikipedia.org/wiki/Predatory\_tunicate
* Meet the Predatory Tunicate | Monterey Bay Aquarium - https://www.montereybayaquarium.org/animals/animals-a-to-z/predatory-tunicate
* From the Depths of Obscurity, Aquarium's New Stars | New York Times - https://www.nytimes.com/1998/12/22/science/from-depths-of-obscurity-aquarium-s-new-stars.html