Figure 1. Hand drawing by Anna Epelbaum
Figure 2. Botrylloides violaceus
Figure 3. Botrylloides violaceus on Petri dish.
Figure 4. Botrylloides violaceus
Figure 5. Botrylloides violaceus
Distinguishing Features:
- Colonial tunicate
- Colony usually one solid colour (purple, pink, yellow, orange, or white)
- Zooids upright (vertical to substrate)
- Usually organized into systems of elongated rows
Origin:
Japan
Habitat and Growth:
Botrylloides violaceus is a shallow subtidal (<50m) tunicate found mainly in protected areas growing on both natural and artificial hard surfaces. This tunicate is known to withstand polluted habitats.
Reproduction:
The colony can regrow and reproduce from fragments. Larvae remain in the water column for less than a day before settling on a hard substrate to grow into juvenile tunicate colonies.
Can be Confused With:
- Most sponges - Tunicates have a gelatinous texture as opposed to a soft and spongy texture.
- Botryllus schlosseri - Unlike the violet tunicate, these colonies are two-toned with zooids arranged in star patterns (see next page).
Management:
Remove colonial tunicates manually and place in garbage receptacle or let dry out of the water. If you must pressure wash colonial tunicates off equipment, only do so on land (not on the farm) and make sure the outflow does not go into the sea, as these colonies can re-grow from small fragments. Completely dry culture gear before placing it back in t the water or moving it between sites.