[3] A vigorous and highly invasive species, the Ciona robusta is a solitary, marine invertebrate attached at its base to a substrate, with a water-filled, sac-like body structure.

[4] Ciona robusta has a translucent tunic and white or off-white body, with orange to red dots on the scalloped edges of the siphons.

Water is then drawn into the stomach and intestines using the mucus strings, then finally expelled using the atrial siphon.

They tend to be found in both protected harbors and natural substrates, with areas such as docks, boat hulls, buoys, ropes, pilings, rocks, shells, aquaculture gear, and boulders being common habitats for them.

Ciona savignyi also has a more fragile tunic with much brighter yellow markings on the siphon edges rather than orange and a white not red dot on the vas deferens, and tends to have fewer tentacles around the oral siphon than Ciona robusta, though this tends to be variable.

While there are records of C. robusta going north of Humboldt Bay, they are historical, and the current northern range edge of the species is unknown.

[4] Going across the Atlantic Ocean, C. robusta were collected in Egyptian waters sometime in the early 1800s and was found to be widespread throughout the Mediterranean Sea by the late 1800s.

[6] In South America, species have been found in Mar del Plata, Argentina (1945); San Antonio Este (2005); Puerto Madryn (2005), and occasionally between Santos and Rio de Janeiro.

However, molecular confirmations need to be made to solidify this evidence of C. robusta invasion of South American waters.

More information should be collected that is based on molecular genetics in the future, so as to more fully understand the invasive habits of C. robusta.