How to Distinguish from Similar Species: Other tunicates of similar shape are not usually pinkish-red, or have a wrinkled tunic. The sea peach, Halocynthia aurantia, is a similar smooth, shiny pinkish color but it has broader siphons of unequal size and is taller than it is wide. Of other common local smooth, orange tunicates, Metandrocarpa taylori is a social ascidian, with multiple individuals living near each other and connected by narrow stolons or sheets of tunic. Distaplia occidentalis is a compound ascidian with many individuals within the same tunic.
Geographical Range: Alaska to Point Conception, CA; most common from Washington north. Also northwestern Pacific, circumboreal in the Arctic
Depth Range: Very low intertidal to at least 50 m (540 m in Japan)
Habitat: Hard substrates in well-circulated waters. Sometimes found on floats. Sometimes lives in holes.
is hermaphroditic. Fertilization is external, during the
The tunic is thin but tough, with 12.4% organic content. Just
half the organic matter in the tunic is tunicin (a carbohydrate); the
is protein. Vanadium content of the body is low (but higher
tunic?) Predators include the seastar Orthasterias
The copepod Pygodelphys aquilonarius may live
symbiotically in the
branchial chamber and many invertebrates may live around the base.
Flora and Fairbanks, 1966
Kozloff 1987, 1996
Smith and Carlton, 1975
Liyun, Molly W. Jacobs, and Bill J. Swalla, 2006.
has evolved once on Stolidobranch ascidians. Integrative and
Biology 46:3 pp 255-268
General Notes and Observations: Locations, abundances, unusual behaviors:
Authors and Editors of Page:
Dave Cowles (2005): Created original page