In conclusion, it is already widely agreed that crustacean
hemocyanins are not restricted to serving oxygen-carrying roles
alone but can play a much wider array of roles that vary according
to the animal’s physiological status. Moreover, the location of
crustacean hemocyanins is not restricted to the hemolymph, as they
may be transferred to other tissues, where they can perform other
functions. Accordingly, we detected several hemocyanins in the
gastrolith matrix, a non-cellular temporary structure, where they may
be maintained for the purpose of forming a rigid construct for
calcium storage. As such, we propose that the presence of
hemocyanins in the gastrolith may be required for fast hardening
of the chitin scaffold in the highly dynamic process of gastrolith
formation; however, other possible functions cannot be excluded.