Gray Encrusting Compound Tunicate

Gray Encrusting Compound Tunicate

Scientific Name: Diplosoma listerianum

This is a common encrusting compound tunicate that is commonly found along docks in the Pacific Northwest.  Similar to other tunicates it grows on rocks, barnacles, bivalves, as well as the exoskeleton of a number of crab species.  Though it may appear like a gray goo covering kelp that is growing along docks, it can be quite beautiful when viewed under a dissecting microscope.


Photos and Video by Noah Elkink

References

Lamb, Andrew, and Bernard P. Hanby. Marine Life of the Pacific Northwest: a Photographic Encyclopedia of Invertebrates, Seaweeds and Selected Fishes. Madeira Park, BC, Harbour Publ., 2009.

Transparent Tunicate

Transparent Tunicate

Scientific Name: Corella inflata

This is one of the most transparent tunicates found on the Pacific Coast from Alaska to Southern California.  Water enters the top of the tunicate at the incurrent siphon where it is filtered by the gill slits of the pharynx.  The food is then taken into the mouth and stomach.  The waste material is then expelled through rectum and anus in the atrium and passes out the excurrent siphon.  It is this waste material in the rectum that is most easily seen within the tunicate.

Corella inflata is often confused with the similar species Corella willmerianaC. inflata has a shorter rectum as well as a larger “inflated” atrial chamber in comparison to C. willmeriana (Cathy Carolsfeld and Henry Choong, personal communication, Nov. 7, 2017).

References

Lamb, Andrew, and Bernard P. Hanby. Marine Life of the Pacific Northwest: a Photographic Encyclopedia of Invertebrates, Seaweeds and Selected Fishes. Madeira Park, BC, Harbour Publ., 2009.

Mushroom Compound Tunicate

The Mushroom Compound Tunicate

Author: Pauline Ewoldt

Scientific Name: Distaplia occidentalis


The Mushroom Compound Tunicate or also known as Distaplia occidentalis is distributed in the Northeast Pacific from Alaska to southern California.  The species is common on intertidal rocks and in protected environments.  It’s found from intertidal to 20m depths. The colonial tunicate forms colonies of multiple club- or mushroom-shaped masses or stalked mounds. Its colour is variable from pale orange to purple, grey, yellow or cream. The zooids are circularly arranged or in an oval systems. They are colored white to pale grey. Each zooid has 4 rows of stigmata and the body is divided into two parts: thorax and abdomen.