Description: As with many dorid nudibranchs,
the anus of this species is found on the dorsum
1/3 to 1/4 from the posterior end, ringed by gills (see photo above).
The body is translucent white to pale yellow with deep orange spots, as
well as 10-15 bright orange coronate
the lateral margins and 8-15 orange papillae
around the edge of the oral
veil. The clavus
of the rhinophores
is brownish-orange, and the five non-retractable gills are white with orange
tips. Total length 2.5-15 cm.
Triopha catalinae (Cooper, 1863)
Common name(s): Sea clown nudibranch, Clown nudibranch, Catalina triopha
|Triopha catalinae subtidal from off Sares Head. A metric
ruler is in the background.
|(Photo by: Dave Cowles, July 1997)
How to Distinguish from Similar Species:
This nudibranch is distinctive in our area. No other has the combination
of white body scattered with orange coronate
deep orange on the tips of the gills and rhinophores.
Geographical Range: From the Aleutian
Islands, Alaska to Baja California
Depth Range: Intertidal to 35 m.
Habitat: Rocky areas or around
Biology/Natural History: This is
one of the largest nudibranchs able to crawl on the underside of the surface
film in tide pools. It feeds on bryozoans such as Bugula californica
by digesting the soft parts. Tide pool fish avoid Triopha,
and this is believed to be because of some sort of chemical repellant.
In Washington eggs have been observed in April and June. The coil
of eggs formed is white or cream-colored (photo).
The ribbon of eggs is attached to a solid surface by its shorter edge (photo).
The free edge is wavy and appears like a ribbon.
and Fairbanks, 1966 (as Triopha carpenteri)
and Carlton, 1975 (as Triopha carpenteri)
and Snook, 1955 (as Triopha carpenteri)
et. al., 1980
General Notes and Observations: Locations,
abundances, unusual behaviors:
This nudibranch is usually one of the most commonly found subtidally
along Sares Head and Northwest Island.
Two individuals mating (they are hermaphroditic). This species
mates very readily in aquaria if given half a chance. Photo by Dave
Cowles, July 2000
This individual is laying a string of eggs. View from below.
Photo by Dave Cowles, 2-2004
An underwater photo by Kirt Onthank, June 2007
Although this species can get quite large (the specimen pictured here
is 8 cm long), it can still crawl upside-down clinging to the surface film
of the water, as this individual is doing. The view is from above but since
the animal is upside-down with its foot clinging to the surface film, the
foot is uppermost. Photo by Dave Cowles, July 2017
Authors and Editors of Page:
Dave Cowles (2007): Created original page. (An earlier
version was worked on by Robbie Wheeling)
CSS coding for page developed by Jonathan Cowles (2007)