encrusting tunicate forms lumpy incrustations usually 1-3 cm
in systems (groups) in which each zooid
has its own opening for its oral
(buccal) siphon at the surface of the colony but the atrial
siphons connect to internal canals in the colony.
lead to joint atrial openings in the surface of the colony scattered
species has no densely packed bladder cells or disk-shaped calcareous
The texture is gelatinous or fleshy, usually without any embedded sand
(but sand may sometimes encrust the surface). The pharynx
has 7-15 (usually 8-12) rows of stigmata.
Color is variable: tan, yellowish, gray, opalescent white,
transparent, or orange-brown. Up to 3 cm thick (more often 1
and 30 cm across, irregular shape.
& Forsyth, 1917)
Common name(s): California sea pork, sea pork
|Photomicrograph of Aplidium
californicum, found on dock at Fidalgo Marina.
siphons of many individual
zooids can be seen scattered across the surface. At
the top right
is the common opening to the atrial
siphons of several local zooids.
|(Photo by: Dave Cowles,
July 2009 )
How to Distinguish from
solidum has 12-16 rows of stigmata, forms slabs
up to 5 cm thick,
and is usually red or orange-brown.
Range: Alaska to Baja California
Mexico; Galapagos Islands
Intertidal to 85 m
A variety of solid or
semi-solid substrates, such as docks, tubeworm tubes, crab carapaces,
shells, surge channels. Usually in areas protected from
One of the commonest compound tunicates in semi-protected sites.
Predators of this compound ascidian include the seastars Dermasterias
aequalis, and Pteraster
If this tunicate is cut open the individual zooids
are clearly visible inside. The front portion (thorax) of
basket and atrial
aperture. The middle (abdomen) contains the coiled
gut and esophagus.
The posterior (postabdomen) looks like a long tail and has the ovaries
(yellow), testes (white), and heart.
This species broods its eggs a few at a time, in the atrial
to the pharynx.
The tadpole larvae swim out the atrial
aperture to disperse. During asexual reproduction,
detaches from the body and constricts into a linear series of buds,
of which grows up into a complete new zooid.
The colonies may degenerate during the winter months.
The symbiotic amphipod Polycheria
osborni may be found living in grooves on these
The parasitic copepod Pholeterides
furtiva may be found as well.
and Snook, 1955 (as Amaroucium
and Hanby, 2005
et al., 1980
and O'Clair, 1998
et al., 1985
General Notes and
abundances, unusual behaviors:
This compound tunicate is especially common on the shaded docks of
Another colony from Fidalgo Marina docks, 2012
for a movie showing a closeup of many buccal siphons and a joint
cloacal siphon of a colony, with particles showing the current blowing
out of the cloacal siphon.
Authors and Editors of Page:
Dave Cowles (2009): Created original page
CSS coding for page developed by Jonathan Cowles (2007)