Tidepool Tim says,  “Astarte clams are a tiny bivalve that we know little about.  We get them in our dredge on rocky bottoms but never in great abundance.  They seem to live well in our aquaria for years. Occasionally we will find large starfish working their tube feet on these clams to pry them apart and eat up their innards.  This is very much a common predator-prey relationship. If one looks at the growth rings on these clams they will see that they grow very slowly. It appears that a 1" clam may be more than a decade in age!”