Botrylloides violaceus

Chain tunicate

Botrylloides violaceus

Common name:

Chain tunicate

Scientific name:

Botrylloides violaceus

Alternative common names:

Lined colonial tunicate, orange sheath tunicate, orange tunicate, and violet tunicate.


Description:

Botrylloides violaceus is a thin and lobe-like colonial tunicate with zooids that form long double rows or ladder-like chains. When the chains are short, they sometimes look similar to the flower-like pattern observed in Botryllus schlosseri. Color variations in colonies range from red, yellow, orange, brown, purple and light lavender. Like other colonial tunicates, the B. violaceus colonies are encrusting, with a thickness of 2 – 3 mm, and can be as large as 200 mm × 20 mm. The tunic protecting the zooids is soft and can be easily torn.

Lined colonial tunicate, orange sheath tunicate, orange tunicate, and violet tunicate.

Additional Information


Where does this species come from?

Botrylloides violaceus was first described in Japan in 1927 and is native to the Northwest Pacific from northern Japan to southern Korea and northern China.

What is its invasive status in South Africa?

NEMBA 2020 2020 Category XX: Botrylloides violaceus has not been recorded in South African waters.

Where in South Africa is it a problem?

Botrylloides violaceus has not been recorded in South African waters.

How does it spread?

Ship ballast water and sediment, ship hull fouling and live seafood.

Why is it a problem?

Botrylloides violaceus overgrows shellfish (e.g. mussels) and other sessile invertebrate species. It is a pest to mussel farmers.

What does it look like?

Description: Thin and lobe-like colonial tunicate with zooids that form long double rows or ladder-like chains. Varies in color, ranging from red, yellow, orange, brown, purple and light lavender.

Habitat: Variety of surfaces, such as docks, boat hulls, buoys, ropes, pilings, on top of and underneath rocks, on mussels and solitary sea squirts, seaweeds.

Breeding: Colonial tunicates reproduce both asexually by budding and sexually from fertilized eggs that develop into larvae.