Clubbed Tunicate (Styela Clava)
Figure 1. Styela clava colony
Figure 2. Styela clava close up.
Figure 3. Single Styela clava
Distinguishing Features:
- Solitary ‘club-shaped’ tunicate;
- Tunic (outer skin) is tough, brown, bumpy, and wrinkly;
- Attached to substrate by a stalk (about 1/3 of the total length);
- Two short siphons. closely spaced, with alternate red and tan bands;
- Often overgrown by other fouling organisms.
Origin:
Northwest Pacific Ocean (predominantly Japan and Korea)
Habitat and Growth:
Styela clava is a lower intertidal to subtidal tunicate that is found growing in protected environments, predominantly on artificial structures like pilings aquaculture gear, floats, etc. Styela clava can withstand a wide range of temperatures and salinities, and therefore may be also found in estuarine environments.
Reproduction:
Styela clava is a broadcast spawner, releasing eggs and sperm that can stay in the water column for 1-3 days during spring and summer.
Can be confused with:
- Styela montereyensis, which is longer (up to 30 cm) and more slender. The tunic also has lines and furrows along the entire length. Styela montereyensis has closely spaced siphons, these have no banding and one siphon is curved.
- Styela gibsii, which is shorter (often not over 4 cm) and stalkless.
Management:
To remove solitary tunicates from culture gear: Cut or pull the tunicate off by the stalk. Throw in a bucket for disposal on land (at a landfill).
