|Cyclosalpa bakeri Ritter, 1905
Phylum Chordata / Subphylum Urochordata / Class Thaliacea / Order Salpida / Family Salpidae
This species is one of the more commonly encountered pelagic tunicates of the West Coast. Compared to some of the other salps you may observe, C. bakeri has a relatively thin, flabby test. It is a slow swimmer with delicate tissue that is easily damaged. Solitary individuals (top 2 photos) are pear-shaped (posterior end smaller) with a length between 5 and 15 cm, and 7 body muscles. Distinct white patches lie between each muscle band. The stolon (seen in the solitary individual in the second photo) emerges near muscle band 2.
Aggregates (bottom photo) also have thin flabby tests, and form distinctive radial whorls up to 20 cm diameter with about 12 zooids. Each zooid has a pair of posterior end projections. This species tends to rise to the surface at night while spending daylight hours in deeper water. Growth rates can be impressive (body size increases of 25% per day in aggregates), and individuals can consume at least half the body mass in 24 hours. C. bakeri is wide ranging in tropical and temperate waters, and may be found as far north as the Gulf of Alaska.