top shell with a pearly interior,
no nodes on columella, umbilicus closed, has tan, unbeaded
ridges on a brown background (weathered parts of shell may appear
whorls are slightly convex. Foot has an orange
is usually pinkish or reddish brown.
Calliostoma ligatum (Gould,
Common name(s): Blue top
shell, costate top shell
C. ligatus, C. costatum
|Calliostoma ligatum captured at
Sares Head and held in aquarium,
spring 2004. About 2 cm diameter.
|(Photo by: Dave Cowles)
How to Distinguish from
Similar Species: C.
variegatum (which is found mostly in deep water)
has a shell mostly
tan, yellowish, or pale pink, and the spirals are beaded. C.
annulatum also has beaded spirals and the lower
spiral on each
whorl is blue or purplish.
Range: Prince William SoundAlaska
to San Diego California. Uncommon in southern end of range.
Depth Range: Shallow
intertidal to subtidal.
Abundant in low intertidal in Puget Sound (This is the only Calliostoma
that is abundant in the Sound).
in eel grass and kelp.
Often found on brown algae such as Cystoseira and Macrocystis.
History: Found in and around
kelp beds. Eats the kelp itself and adhering bryozoans,
and detritus. May eat tunicate Cystodytes lobatus.
two muscular waves of contraction on foot while crawling, which move
back to front of the foot and are out of phase with each
rapidly away from some seastars. Snail covers shell with
may aid in avoiding capture by seastars.
According to Baltzley
et al., (2011),
many gastropods, including this species, have a special network of
pedal ganglia in their foot which assists in crawling. The
main neurons involved produce pedal peptides which elicit an increase
in the rate of beating of cilia on the foot, resulting in crawling.
and Carlton, 1975
and Fairbanks, 1966
et al., 1980
Michael J., Allison Serman, Shaun D. Cain, and Kenneth J. Lohmann, 2011.
Conservation of a Tritonia
pedal peptides network in gastropods. Invertebrate Biology
130: 4 pp. 313-324
General Notes and
Observations: Locations, abundances,
unusual behaviors, etc.:
Different individuals may be
slightly different colors. Photo by Dave Cowles, July 2012
An underwater photo by Kirt Onthank, July 2007
This individual has begun to realease a cloud of sperm into
the dish. Photo by Dave Cowles, July 2012
The sperm of Calliostoma
ligatum is pinlike and highly motile. Length
about 12 microns. Photo by Dave Cowles, July 2012
Authors and Editors of Page:
Dave Cowles (2004): Created original page